Power Requirements

[SBFan2000]

Made several PCBs (digitally) and now looking at what power I'll need to
power them. Pretty simple boards, bunch of LEDs, resistors for those LEDs,
relays, and switches. As I said, pretty simple. I need to decide on
voltage as well as the amperage requirement. This is my first project I've
done entirely by myself so just looking for ideas. Do I need to add up the
amperage requirement for each LED? (.020mA) and then the requirement for
each Relay and then thats my requirement? Does this need to be done for the
voltage? If each LED is 2VDC and .020mA and I have 10 does that mean I need
20VDC at .200mA or just 2VDC at .200mA?

There is no amperage requirement for resistors, correct? Also the current
will be flowing through 100feet of cable, I'm assuming I need to figure in
resistance at that kind of length?

Thanks for any help!

 

[Ross Herbert]

On Thu, 14 Dec 2006 00:32:29 GMT, "SBFan2000"
<glenn@glenngriffithNOSPAM.com> wrote:

Made several PCBs (digitally) and now looking at what power I'll need to
power them. Pretty simple boards, bunch of LEDs, resistors for those LEDs,
relays, and switches. As I said, pretty simple. I need to decide on
voltage as well as the amperage requirement. This is my first project I've
done entirely by myself so just looking for ideas. Do I need to add up the
amperage requirement for each LED? (.020mA) and then the requirement for
each Relay and then thats my requirement? Does this need to be done for the
voltage? If each LED is 2VDC and .020mA and I have 10 does that mean I need
20VDC at .200mA or just 2VDC at .200mA?

There is no amperage requirement for resistors, correct? Also the current
will be flowing through 100feet of cable, I'm assuming I need to figure in
resistance at that kind of length?

Thanks for any help!

I don't want to decry your efforts concerning your venture with making
your first pcb's but I make the observation that you seem to have
tackled this back to front

When designing a pcb it is generally known beforehand what the circuit
design will be and what components will be used. Only with this
knowledge beforehand can you determine the component layout and what
thickness and spacing requirements are for the copper tracks. Each pcb
you design will be specific to the design project, except in the case
you are producing a general purpose bredboarding type pcb. Usually,
one doesn't make breadboarding pcb's these days except for special
cases and in most cases using a protoboard is the way to go to settle
on a final design. Only when the design is finalised do you design the
pcb.

Having said that, your brief description requiring driving of leds,
relays and switches will be dependant upon the pcb layout. For
example, if you have laid out the pcb so that the leds are in series
then the voltage requirement to drive them will be higher than if you
have arranged the leds to be driven in parallel. Also, depending upon
the led colour, the voltage requirements will be different for each
led colour. Then if you use high efficiency leds these require no more
than 5mA for operation.

If you get my drift, what I am saying is do things the right order -
circuit design, prototype construction, pcb design, first-final build
in that order. (In many cases the first-final build - as implied -
will not be the last, except for the simplest designs.

Good luck with your project.

 

[SBFan2000]

I did pick out final components except for the relays. I'm not entirely
understanding how they are rated. I left room on the PCBs to accomidate
most relays pins. I had a good idea of the voltage I wanted to use. I had
selected 24vdc but was wondering if 12 or 18vdc would be enough.

Basically I want a button that I push on a "control panel" to travel the
100ft to a relay which then turns on a 115vac supply. Like I said I'm
having issues understanding the way relays are rated. Assuming I go with
24vdc I would need a relay with a coil rated at 24vdc and a N.O. switch that
can handle 115vac at 10-20A, correct?

All leds are either red or green and based on what I read are 2vdc at
..020mA. I do have 3-4 blue leds which I read at 4vdc and .040mA (if memory
serves) Could you explain "in series" and "in Parallel." The way I
understand it (and I could be wrong) Parallel would be having power go from
one led to the other in a chain? Serial would be a home run track, back to
power, for each led. In this case parallel is the way I did it. (with a
resistor for each led)

I didn't mean to imply that the PCBs are totally done. They are merely to
the point where I can no longer put off relay selection. That all said, I
don't doubt I'm doing things wrong and backwards, it is my first PCB from
scratch. (I've repaired them at work)

How about these:
http://cgi.ebay.com/Tyco-Relays-SPST-NO-Coil-24V-Contact-10A-PCB_W0QQitemZ120060224418QQihZ002QQcategoryZ42897QQrdZ1QQssPageNameZWD1VQQcmdZViewItem




"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:ms81o2lfgv01fepht7h5jabqibftfsa21l@4ax.com...

On Thu, 14 Dec 2006 00:32:29 GMT, "SBFan2000"
glenn@glenngriffithNOSPAM.com> wrote:

Made several PCBs (digitally) and now looking at what power I'll need to
power them. Pretty simple boards, bunch of LEDs, resistors for those
LEDs,
relays, and switches. As I said, pretty simple. I need to decide
on
voltage as well as the amperage requirement. This is my first project
I've
done entirely by myself so just looking for ideas. Do I need to add up
the
amperage requirement for each LED? (.020mA) and then the requirement for
each Relay and then thats my requirement? Does this need to be done for
the
voltage? If each LED is 2VDC and .020mA and I have 10 does that mean I
need
20VDC at .200mA or just 2VDC at .200mA?

There is no amperage requirement for resistors, correct? Also the
current
will be flowing through 100feet of cable, I'm assuming I need to figure
in
resistance at that kind of length?

Thanks for any help!



I don't want to decry your efforts concerning your venture with making
your first pcb's but I make the observation that you seem to have
tackled this back to front

When designing a pcb it is generally known beforehand what the circuit
design will be and what components will be used. Only with this
knowledge beforehand can you determine the component layout and what
thickness and spacing requirements are for the copper tracks. Each pcb
you design will be specific to the design project, except in the case
you are producing a general purpose bredboarding type pcb. Usually,
one doesn't make breadboarding pcb's these days except for special
cases and in most cases using a protoboard is the way to go to settle
on a final design. Only when the design is finalised do you design the
pcb.

Having said that, your brief description requiring driving of leds,
relays and switches will be dependant upon the pcb layout. For
example, if you have laid out the pcb so that the leds are in series
then the voltage requirement to drive them will be higher than if you
have arranged the leds to be driven in parallel. Also, depending upon
the led colour, the voltage requirements will be different for each
led colour. Then if you use high efficiency leds these require no more
than 5mA for operation.

If you get my drift, what I am saying is do things the right order -
circuit design, prototype construction, pcb design, first-final build
in that order. (In many cases the first-final build - as implied -
will not be the last, except for the simplest designs.

Good luck with your project.

 

[Ross Herbert]

On Thu, 14 Dec 2006 02:02:22 GMT, "SBFan2000"
<glenn@glenngriffithNOSPAM.com> wrote:

I did pick out final components except for the relays. I'm not entirely
understanding how they are rated. I left room on the PCBs to accomidate
most relays pins. I had a good idea of the voltage I wanted to use. I had
selected 24vdc but was wondering if 12 or 18vdc would be enough.

Basically I want a button that I push on a "control panel" to travel the
100ft to a relay which then turns on a 115vac supply. Like I said I'm
having issues understanding the way relays are rated. Assuming I go with
24vdc I would need a relay with a coil rated at 24vdc and a N.O. switch that
can handle 115vac at 10-20A, correct?

You could use any voltage you like depending upon what guage wire you
use for the 100ft link. Generally any voltage from 12V - 24V would be
quite suitable if you use twin conductor cable with conductors of
0.4mm (26AWG) diameter (or better) copper.

All leds are either red or green and based on what I read are 2vdc at
.020mA. I do have 3-4 blue leds which I read at 4vdc and .040mA (if memory
serves) Could you explain "in series" and "in Parallel." The way I
understand it (and I could be wrong) Parallel would be having power go from
one led to the other in a chain? Serial would be a home run track, back to
power, for each led. In this case parallel is the way I did it. (with a
resistor for each led)

Oh dear me.... are you sure you should be getting into a project
involving 115Vac? If you don't understand what series and parallel
connections for low voltage components such as leds then you could get
yourself killed when playing around with lethal voltages and currents.
Have you tried doing some basic research into the meaning of these
terms? - Google is your friend...

I would never connect leds of different colours in a series string
because they all have different voltage requirements. I would only
connect leds of the same colour in any individual series string.

I didn't mean to imply that the PCBs are totally done. They are merely to
the point where I can no longer put off relay selection. That all said, I
don't doubt I'm doing things wrong and backwards, it is my first PCB from
scratch. (I've repaired them at work)

How about these:
http://cgi.ebay.com/Tyco-Relays-SPST-NO-Coil-24V-Contact-10A-PCB_W0QQitemZ120060224418QQihZ002QQcategoryZ42897QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

It depends on what type of load you are planning to control with the
relay output. That particular relay is only rated to switch 10A @
250Vac into a resistive load. Also, it can only switch a maximum load
of 280W. You would not use it to control an inductive load such as a
115Vac electric motor or pump.

See full data sheet here
http://relays.tycoelectronics.com/datasheets/OJ-OJE.pdf

What type of load are you intending to drive?

 

[SBFan2000]

"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:5qe2o2tu4od4n4li87lvb4nfmfrbjvp467@4ax.com...

On Thu, 14 Dec 2006 02:02:22 GMT, "SBFan2000"
glenn@glenngriffithNOSPAM.com> wrote:

I did pick out final components except for the relays. I'm not entirely
understanding how they are rated. I left room on the PCBs to accomidate
most relays pins. I had a good idea of the voltage I wanted to use. I
had
selected 24vdc but was wondering if 12 or 18vdc would be enough.

Basically I want a button that I push on a "control panel" to travel the
100ft to a relay which then turns on a 115vac supply. Like I said I'm
having issues understanding the way relays are rated. Assuming I go with
24vdc I would need a relay with a coil rated at 24vdc and a N.O. switch
that
can handle 115vac at 10-20A, correct?

You could use any voltage you like depending upon what guage wire you
use for the 100ft link. Generally any voltage from 12V - 24V would be
quite suitable if you use twin conductor cable with conductors of
0.4mm (26AWG) diameter (or better) copper.

Understood

All leds are either red or green and based on what I read are 2vdc at
.020mA. I do have 3-4 blue leds which I read at 4vdc and .040mA (if
memory
serves) Could you explain "in series" and "in Parallel." The way I
understand it (and I could be wrong) Parallel would be having power go
from
one led to the other in a chain? Serial would be a home run track, back
to
power, for each led. In this case parallel is the way I did it. (with a
resistor for each led)

Oh dear me.... are you sure you should be getting into a project
involving 115Vac? If you don't understand what series and parallel
connections for low voltage components such as leds then you could get
yourself killed when playing around with lethal voltages and currents.
Have you tried doing some basic research into the meaning of these
terms? - Google is your friend...

Could you please explain series and parallel so I can verify what I have
already researched and read on the subject instead of just saying that if I
don't understand it I'm to stupid to deal with it?

I would never connect leds of different colours in a series string
because they all have different voltage requirements. I would only
connect leds of the same colour in any individual series string.

I didn't. I have three different colors but no colors are mixed with other
colors. Both my red and green leds are all 2VDC and the 3 Blues are 4VDC.
Technically I could connect the red and greens but I didn't. Every single
LED in the system also has its own dedicated resistor. I'm not using one
resistor for the entire string because (from what I researched) a led with
slightly different requirements could burnout. This thing already has
almost 100 resistors if that give you an idea of the LEDs required.

I didn't mean to imply that the PCBs are totally done. They are merely
to
the point where I can no longer put off relay selection. That all said,
I
don't doubt I'm doing things wrong and backwards, it is my first PCB from
scratch. (I've repaired them at work)

How about these:

http://cgi.ebay.com/Tyco-Relays-SPST-NO-Coil-24V-Contact-10A-PCB_W0QQitemZ1
20060224418QQihZ002QQcategoryZ42897QQrdZ1QQssPageNameZWD1VQQcmdZViewItem


It depends on what type of load you are planning to control with the
relay output. That particular relay is only rated to switch 10A @
250Vac into a resistive load. Also, it can only switch a maximum load
of 280W. You would not use it to control an inductive load such as a
115Vac electric motor or pump.

10A should be fine. Just using standard home outlet to supply this thing.
I can make sure I use a 10 breaker or I can build a 10A (or slightly less)
fuse into the system.

See full data sheet here
http://relays.tycoelectronics.com/datasheets/OJ-OJE.pdf

What type of load are you intending to drive?

Boy you'll love this, A short circuit! Basically a low gauge wire
connected to positive and negative that will burn up when the relay is
tripped. A light bulb with out the glass, basically. I should say that I
have already built this and used it twice it works quite well. The current
system uses 115Vac at 15A for the entire system. I'm just redesigning to
get the controls and the majority of the rest of the system at lower
voltage. I thought of using 24VDC for the whole thing but a trace on one of
the boards could burn up instead of the filament. Thats the reason for the
relays to isolate the short from the rest of the system. I suppose I could
have one PSU (24VDC) for the system side and another for the "short" side.
it would be slightly safer.

 

[Ross Herbert]

On Thu, 14 Dec 2006 22:45:44 GMT, "SBFan2000"
<glenn@glenngriffithNOSPAM.com> wrote:

"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:5qe2o2tu4od4n4li87lvb4nfmfrbjvp467@4ax.com...
On Thu, 14 Dec 2006 02:02:22 GMT, "SBFan2000"
glenn@glenngriffithNOSPAM.com> wrote:

I did pick out final components except for the relays. I'm not entirely
understanding how they are rated. I left room on the PCBs to accomidate
most relays pins. I had a good idea of the voltage I wanted to use. I
had
selected 24vdc but was wondering if 12 or 18vdc would be enough.

Basically I want a button that I push on a "control panel" to travel the
100ft to a relay which then turns on a 115vac supply. Like I said I'm
having issues understanding the way relays are rated. Assuming I go with
24vdc I would need a relay with a coil rated at 24vdc and a N.O. switch
that
can handle 115vac at 10-20A, correct?

On reading the explanation of the type of load you wish to drive (last
paragraph below) it seems I may have interpreted that you wanted the
relay contact to control the 115Vac output.

When you said "I would need a relay with a coil rated at 24vdc and a
N.O. switch that can handle 115vac at 10-20A, correct?" I thought you
were referring to the N.O. contact on the relay as the "N.O. switch"
which needed to be rated for 115Vac at 10 - 20A, but it appears that
the N.O. switch you were referring to may be the switch used to cause
the operation of the 24V relay at the remote end of the 100 ft cable.
Is this correct?

The switch used to control the relay coil only needs to be capable of
handling a maximum of 1 - 2A at the operating voltage of 24Vdc. It
won't matter if you do use a higher rated switch for this function.

A sketch of what you are trying to achieve would be helpful.

You could use any voltage you like depending upon what guage wire you
use for the 100ft link. Generally any voltage from 12V - 24V would be
quite suitable if you use twin conductor cable with conductors of
0.4mm (26AWG) diameter (or better) copper.

Understood



All leds are either red or green and based on what I read are 2vdc at
.020mA. I do have 3-4 blue leds which I read at 4vdc and .040mA (if
memory
serves) Could you explain "in series" and "in Parallel." The way I
understand it (and I could be wrong) Parallel would be having power go
from
one led to the other in a chain? Serial would be a home run track, back
to
power, for each led. In this case parallel is the way I did it. (with a
resistor for each led)

Oh dear me.... are you sure you should be getting into a project
involving 115Vac? If you don't understand what series and parallel
connections for low voltage components such as leds then you could get
yourself killed when playing around with lethal voltages and currents.
Have you tried doing some basic research into the meaning of these
terms? - Google is your friend...

Could you please explain series and parallel so I can verify what I have
already researched and read on the subject instead of just saying that if I
don't understand it I'm to stupid to deal with it?

Basic explanation of series and parallel circuits
http://www.allaboutcircuits.com/vol_1/chpt_5/1.html

Connecting LED's in series (20mA types)
http://unclean.org/howto/led_circuit.html

If you haven't been here then it is a good place to start
http://led.linear1.org/

They have a LED series parallel calculator wizard
http://led.linear1.org/led.wiz

I would never connect leds of different colours in a series string
because they all have different voltage requirements. I would only
connect leds of the same colour in any individual series string.

I didn't. I have three different colors but no colors are mixed with other
colors. Both my red and green leds are all 2VDC and the 3 Blues are 4VDC.
Technically I could connect the red and greens but I didn't. Every single
LED in the system also has its own dedicated resistor. I'm not using one
resistor for the entire string because (from what I researched) a led with
slightly different requirements could burnout. This thing already has
almost 100 resistors if that give you an idea of the LEDs required.

Try using the LED calculator wizard in the link above to check out the
circuit arrangement for each of the LED colour arrays you are
building.

I didn't mean to imply that the PCBs are totally done. They are merely
to
the point where I can no longer put off relay selection. That all said,
I
don't doubt I'm doing things wrong and backwards, it is my first PCB from
scratch. (I've repaired them at work)

How about these:

http://cgi.ebay.com/Tyco-Relays-SPST-NO-Coil-24V-Contact-10A-PCB_W0QQitemZ1
20060224418QQihZ002QQcategoryZ42897QQrdZ1QQssPageNameZWD1VQQcmdZViewItem


It depends on what type of load you are planning to control with the
relay output. That particular relay is only rated to switch 10A @
250Vac into a resistive load. Also, it can only switch a maximum load
of 280W. You would not use it to control an inductive load such as a
115Vac electric motor or pump.

10A should be fine. Just using standard home outlet to supply this thing.
I can make sure I use a 10 breaker or I can build a 10A (or slightly less)
fuse into the system.


See full data sheet here
http://relays.tycoelectronics.com/datasheets/OJ-OJE.pdf

What type of load are you intending to drive?

Boy you'll love this, A short circuit! Basically a low gauge wire
connected to positive and negative that will burn up when the relay is
tripped. A light bulb with out the glass, basically. I should say that I
have already built this and used it twice it works quite well. The current
system uses 115Vac at 15A for the entire system. I'm just redesigning to
get the controls and the majority of the rest of the system at lower
voltage. I thought of using 24VDC for the whole thing but a trace on one of
the boards could burn up instead of the filament. Thats the reason for the
relays to isolate the short from the rest of the system. I suppose I could
have one PSU (24VDC) for the system side and another for the "short" side.
it would be slightly safer.

You will needa separate low power 24V dc supply to drive the relay
coil - 100mA output capability would be suitable for the relay you
have nominated.

Use a separate high power 24V dc supply for the output (load side).
This will need to be a fairly robust supply and may not need to be a
regulated supply - a simple brute force mains transformer, bridge
rectifier and filter capacitor arrangement with a hefty output circuit
breaker or fuse (say 50A).

The problem I see for the relay you have nominated is that the relay
contacts will either be welded together or simply blasted away as soon
as they make to supply 24V to the short circuit load. It is not going
to be suitable for what you want to do. A pcb mounted relay will not
be the way to go.

For the function you require to perform you need a heavy duty
contactor or mercury relay to handle the fast high current surge you
will produce.

Something like these would be suitable
http://www.tempco.com/Accessories/Mercury_Displacement_Relays.htm

Note: to drive the 24V dc coil of a RLY01355 (35A rating) you would
need a 24Vdc coil supply capable of around 250mA.

 

[jasen]

On 2006-12-14, Ross Herbert <rherber1@bigpond.net.au> wrote:

I would never connect leds of different colours in a series string
because they all have different voltage requirements. I would only
connect leds of the same colour in any individual series string.

theres no risa as long as the LEDs are all happy with the same current,
LEDs aren't controlled by voltage anyway, they're controlled by current
and drop whatever voltage they need.

Bye.
Jasen

 

[SBFan2000]

Basically I want a button that I push on a "control panel" to travel the

100ft to a relay which then turns on a 115vac supply. Like I said I'm
having issues understanding the way relays are rated. Assuming I go
with
24vdc I would need a relay with a coil rated at 24vdc and a N.O.
switch
that
can handle 115vac at 10-20A, correct?

On reading the explanation of the type of load you wish to drive (last
paragraph below) it seems I may have interpreted that you wanted the
relay contact to control the 115Vac output.

Yes, this is correct. However, after I posted this I realized it would not
work. I would be risking melting the relay instead of the "filament" that I
want to blow. Is this correct?

When you said "I would need a relay with a coil rated at 24vdc and a
N.O. switch that can handle 115vac at 10-20A, correct?" I thought you
were referring to the N.O. contact on the relay as the "N.O. switch"
which needed to be rated for 115Vac at 10 - 20A, but it appears that
the N.O. switch you were referring to may be the switch used to cause
the operation of the 24V relay at the remote end of the 100 ft cable.
Is this correct?

No, the remote end would have simple push buttons and leds which when the
button is push would send 12-24VDC to the relay causing it to trip the
150Vac side and blowing the filament. However, as I said above, I'm
thinking this will not work because the relay would like blow instead of the
filment. Want I was thinking since I last posted was, model rocket
ignitors. They only require 6-9VDC to ignite so I could forget about the
115VAC. (I case you haven't figured it out, I'm looking to fire off
fireworks while a safe distance away and in quick succession.) So my new
question would be, can those relays I was looking at handle the 6-9VDC
without damage? (I'm looking to do this as cheap as possible and those
relays are $ .49.)

The switch used to control the relay coil only needs to be capable of
handling a maximum of 1 - 2A at the operating voltage of 24Vdc. It
won't matter if you do use a higher rated switch for this function.

A sketch of what you are trying to achieve would be helpful.

You don't happen to have PCD wizard do you. Thats what I'm using!

You could use any voltage you like depending upon what guage wire you
use for the 100ft link. Generally any voltage from 12V - 24V would be
quite suitable if you use twin conductor cable with conductors of
0.4mm (26AWG) diameter (or better) copper.

Understood



All leds are either red or green and based on what I read are 2vdc at
.020mA. I do have 3-4 blue leds which I read at 4vdc and .040mA (if
memory
serves) Could you explain "in series" and "in Parallel." The way I
understand it (and I could be wrong) Parallel would be having power
go
from
one led to the other in a chain? Serial would be a home run track,
back
to
power, for each led. In this case parallel is the way I did it.
(with a
resistor for each led)

Oh dear me.... are you sure you should be getting into a project
involving 115Vac? If you don't understand what series and parallel
connections for low voltage components such as leds then you could get
yourself killed when playing around with lethal voltages and currents.
Have you tried doing some basic research into the meaning of these
terms? - Google is your friend...

Could you please explain series and parallel so I can verify what I have
already researched and read on the subject instead of just saying that if
I
don't understand it I'm to stupid to deal with it?

Basic explanation of series and parallel circuits
http://www.allaboutcircuits.com/vol_1/chpt_5/1.html

Connecting LED's in series (20mA types)
http://unclean.org/howto/led_circuit.html

If you haven't been here then it is a good place to start
http://led.linear1.org/

They have a LED series parallel calculator wizard
http://led.linear1.org/led.wiz



I would never connect leds of different colours in a series string
because they all have different voltage requirements. I would only
connect leds of the same colour in any individual series string.

I didn't. I have three different colors but no colors are mixed with
other
colors. Both my red and green leds are all 2VDC and the 3 Blues are
4VDC.
Technically I could connect the red and greens but I didn't. Every
single
LED in the system also has its own dedicated resistor. I'm not using one
resistor for the entire string because (from what I researched) a led
with
slightly different requirements could burnout. This thing already has
almost 100 resistors if that give you an idea of the LEDs required.


Try using the LED calculator wizard in the link above to check out the
circuit arrangement for each of the LED colour arrays you are
building.



I didn't mean to imply that the PCBs are totally done. They are
merely
to
the point where I can no longer put off relay selection. That all
said,
I
don't doubt I'm doing things wrong and backwards, it is my first PCB
from
scratch. (I've repaired them at work)

How about these:


http://cgi.ebay.com/Tyco-Relays-SPST-NO-Coil-24V-Contact-10A-PCB_W0QQitemZ
1
20060224418QQihZ002QQcategoryZ42897QQrdZ1QQssPageNameZWD1VQQcmdZViewItem


It depends on what type of load you are planning to control with the
relay output. That particular relay is only rated to switch 10A @
250Vac into a resistive load. Also, it can only switch a maximum load
of 280W. You would not use it to control an inductive load such as a
115Vac electric motor or pump.

10A should be fine. Just using standard home outlet to supply this
thing.
I can make sure I use a 10 breaker or I can build a 10A (or slightly
less)
fuse into the system.


See full data sheet here
http://relays.tycoelectronics.com/datasheets/OJ-OJE.pdf

What type of load are you intending to drive?

Boy you'll love this, A short circuit! Basically a low gauge wire
connected to positive and negative that will burn up when the relay is
tripped. A light bulb with out the glass, basically. I should say that
I
have already built this and used it twice it works quite well. The
current
system uses 115Vac at 15A for the entire system. I'm just redesigning to
get the controls and the majority of the rest of the system at lower
voltage. I thought of using 24VDC for the whole thing but a trace on one
of
the boards could burn up instead of the filament. Thats the reason for
the
relays to isolate the short from the rest of the system. I suppose I
could
have one PSU (24VDC) for the system side and another for the "short"
side.
it would be slightly safer.


You will needa separate low power 24V dc supply to drive the relay
coil - 100mA output capability would be suitable for the relay you
have nominated.

Use a separate high power 24V dc supply for the output (load side).
This will need to be a fairly robust supply and may not need to be a
regulated supply - a simple brute force mains transformer, bridge
rectifier and filter capacitor arrangement with a hefty output circuit
breaker or fuse (say 50A).

The problem I see for the relay you have nominated is that the relay
contacts will either be welded together or simply blasted away as soon
as they make to supply 24V to the short circuit load. It is not going
to be suitable for what you want to do. A pcb mounted relay will not
be the way to go.

For the function you require to perform you need a heavy duty
contactor or mercury relay to handle the fast high current surge you
will produce.

Something like these would be suitable
http://www.tempco.com/Accessories/Mercury_Displacement_Relays.htm

Note: to drive the 24V dc coil of a RLY01355 (35A rating) you would
need a 24Vdc coil supply capable of around 250mA.

 

[JeffM]

Ross Herbert wrote:

A sketch of what you are trying to achieve would be helpful.
..

SBFan2000 wrote:

You don't happen to have PCD wizard do you. Thats what I'm using!

It's customary NOT to remove from your blockquote
the name of the person to whom you are responding.

So, how were you planning to convey this graphic to Ross?
How about to everyone else reading the thread?
(Groups without **binary** or **binaries** in their names
are text-only and typically have attachments stripped off
at the 1st server the post encounters.)

Most people find it easy to use a monospaced font like Courier
to make ASCII diagrams of simple circuits--even complex ones--
then cut & paste that into the post.

This tool (Andy's ASCII Circuit) is often used:
(translated from German)
http://translate.google.com/translate?u=http://www.tech-chat.de/aacircuit.html+&langpair=de%7Cen
Try the *ASCII Circuits* link to see examples.

 

[SBFan2000]

"JeffM" <jeffm_@email.com> wrote in message
news:1166464629.978887.210890@48g2000cwx.googlegroups.com...

Ross Herbert wrote:
A sketch of what you are trying to achieve would be helpful.
.
SBFan2000 wrote:
You don't happen to have PCD wizard do you. Thats what I'm using!

It's customary NOT to remove from your blockquote
the name of the person to whom you are responding.

So, how were you planning to convey this graphic to Ross?

Ever heard of E-mail??

How about to everyone else reading the thread?
(Groups without **binary** or **binaries** in their names
are text-only and typically have attachments stripped off
at the 1st server the post encounters.)

Most people find it easy to use a monospaced font like Courier
to make ASCII diagrams of simple circuits--even complex ones--
then cut & paste that into the post.

This tool (Andy's ASCII Circuit) is often used:
(translated from German)

http://translate.google.com/translate?u=http://www.tech-chat.de/aacircuit.html+&langpair=de%7Cen
Try the *ASCII Circuits* link to see examples.

 

[SBFan2000]

Anyone got a good supplier for PCB components! I'm looking at a couple but
was wondering what others are using?

 

[Ross Herbert]

On Tue, 19 Dec 2006 03:00:00 GMT, "SBFan2000"
<glenn@glenngriffithNOSPAM.com> wrote:

Anyone got a good supplier for PCB components! I'm looking at a couple but
was wondering what others are using?

I am sorry to have to say this but when you ask such an open ended,
non-specific question such as this I wonder how you managed to get
this far on the NG without somebody jumping on you. I mean - "PCB
components" have been around even before the PCB was first devised.
Virtually any passive component (resistor, capacitor, inductor,
transformer etc) can be PCB mounted. Before PCB's, components were
mounted on stripboard or bare phenolic or fibreglass board with
soldered wire links. The very same components can also be mounted on
PCB's.

If you want help then you have to be more specific because there are a
million places which anyone who has even the vaguest interest in
electronics will know of. Why don't you just try Googling for
electronic components of the type you need?

YOu need to think more logically before putting fingers to the
keyboard.

 

[SBFan2000]

My God, what is the problem? Did you not read that I have already found and
are "looking at a few sources." I'm not so stupid as to not try google.
The supplier I'm looking at now has everything you could imagine. Their
catalog is nearly 1000 pages. I was just wondering if anyone out there had
any sources that they use that might be better.

Every post that I make results in some smartass worthless post. I already
admitted that I'm new at this what else do you want? If I knew all this
stuff then I wouldn't be asking for help. I'm trying to learn and if you
are unwilling to teach then I would suggest you not reply to my posts. I
belong and lurk at many other boards and they don't (for the most part) have
these worthless responses. Those newsgroups help each other and are
understanding and helpful to the newbies. This group just keeps knocking
the newbie down. I get it, I'm new and you are all electronic gods. "How
dare the little old newbie ask a question, hes not worthy to talk to the
likes of me."

I don't need this. I'll just stay with asking the electical engineer at
work. I was trying not to bother him but when I started get worthless
responses I went ahead and asked and he, unlike the people here, was more
than willing to help, even with his super busy schedule. He even gave me an
old breadboard that he had. Today I asked about sources for "PCB components
for making my first board" and he gave me a two huge catalogs. He didn't
give me shit about not asking a specific question. Its so nice to find
someone willing to help I wish I could have found it here.

Ross, I do appreciate the links you provided. They helped and I did
understand serial vs. parallel but at least the link verified that. You
were the closest to being helpful.

As for the rest of the group, its just not worth it. You people are so
negative and unhelpful that its really sad. I'm unsubscribing from this
"I'm better than you" group. If anyone wants to be friendly and actually
helpful you may contact me directly. I'm the most friendly guy you'll ever
meet when I not being ridiculed!

"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:bcoeo2pvf71o4vklqlqjlu3l5pu45hcj42@4ax.com...

On Tue, 19 Dec 2006 03:00:00 GMT, "SBFan2000"
glenn@glenngriffithNOSPAM.com> wrote:

Anyone got a good supplier for PCB components! I'm looking at a couple
but
was wondering what others are using?


I am sorry to have to say this but when you ask such an open ended,
non-specific question such as this I wonder how you managed to get
this far on the NG without somebody jumping on you. I mean - "PCB
components" have been around even before the PCB was first devised.

Thats interesting, the "PCB component" was around BEFORE the PCB! That must
have been hard for people having all these "PCB components" and not having
anywhere to put them or for that matter even knowing what a PCB was. I
would suggest that they may not have been called "PCB components" if the PCB
didn't yet exist.

Virtually any passive component (resistor, capacitor, inductor,
transformer etc) can be PCB mounted.

Thereby making them a "PCB component" and a subject of my request. Perhaps
you could have suggested a place to purchase them.

Before PCB's, components were
mounted on stripboard or bare phenolic or fibreglass board with
soldered wire links. The very same components can also be mounted on
PCB's.

If you want help then you have to be more specific because there are a
million places which anyone who has even the vaguest interest in
electronics will know of. Why don't you just try Googling for
electronic components of the type you need?

I have! Imagine that! I've found most of what I need but would rather
place one or two orders from large suppliers instead of 10-15 little guys!
Hence the question.

YOu need to think more logically before putting fingers to the
keyboard.

And you need to stick to the question asked or ask a polite counter
question.


EVERYONE HAVE A MERRY CHRISTMAS!

 

[John Fields]

On Tue, 19 Dec 2006 22:29:54 GMT, "SBFan2000"
<glenn@glenngriffithNOSPAM.com> wrote:

My God, what is the problem? Did you not read that I have already found and
are "looking at a few sources." I'm not so stupid as to not try google.
The supplier I'm looking at now has everything you could imagine. Their
catalog is nearly 1000 pages. I was just wondering if anyone out there had
any sources that they use that might be better.

---
Why would it matter? From what I've read so far you don't even know
how to choose parts, or you don't know how they work, or you don't
even know how to calculate the resistance of a length of wire, so
where they come from is really unimportant.
---

Every post that I make results in some smartass worthless post. I already
admitted that I'm new at this what else do you want? If I knew all this
stuff then I wouldn't be asking for help. I'm trying to learn and if you
are unwilling to teach then I would suggest you not reply to my posts. I
belong and lurk at many other boards and they don't (for the most part) have
these worthless responses. Those newsgroups help each other and are
understanding and helpful to the newbies. This group just keeps knocking
the newbie down. I get it, I'm new and you are all electronic gods. "How
dare the little old newbie ask a question, hes not worthy to talk to the
likes of me."

---
This is alt.electronics, where the attitudes might be a little less
condescending than on sci.electronics.basics, where you might be
slapped around a little less. Try it. Basically, there are no
stupid questions on abse.
---

I don't need this. I'll just stay with asking the electical engineer at
work. I was trying not to bother him but when I started get worthless
responses I went ahead and asked and he, unlike the people here, was more
than willing to help, even with his super busy schedule. He even gave me an
old breadboard that he had. Today I asked about sources for "PCB components
for making my first board" and he gave me a two huge catalogs. He didn't
give me shit about not asking a specific question. Its so nice to find
someone willing to help I wish I could have found it here.

---
Damn!, it seems like you're pissed because people here have told you
that you're going about your business in a way that's bassackwards
and you don't want to hear that. OK. So take a hike and figure it
out for yourself.
---

Ross, I do appreciate the links you provided. They helped and I did
understand serial vs. parallel but at least the link verified that. You
were the closest to being helpful.

As for the rest of the group, its just not worth it. You people are so
negative and unhelpful that its really sad. I'm unsubscribing from this
"I'm better than you" group. If anyone wants to be friendly and actually
helpful you may contact me directly.

---
Why? For the great honor of being able to tutor you, LOL?
---

I'm the most friendly guy you'll ever meet when I not being ridiculed!

---
I suspect, then, that you really pretty hostile most of the time.


--
JF

 

[John Fields]

On Tue, 19 Dec 2006 19:18:40 -0800, John Fields
<jfields@austininstruments.com> wrote:

Basically, there are no
stupid questions on abse.

---
seb

--
JF

 

[Ross Herbert]

On Tue, 19 Dec 2006 22:29:54 GMT, "SBFan2000"
<glenn@glenngriffithNOSPAM.com> wrote:

My God, what is the problem? Did you not read that I have already found and
are "looking at a few sources." I'm not so stupid as to not try google.
The supplier I'm looking at now has everything you could imagine. Their
catalog is nearly 1000 pages. I was just wondering if anyone out there had
any sources that they use that might be better.

Yes I did read. Your query was'

"Anyone got a good supplier for PCB components!..."

If you caught the gist of my reply then it will have been apparent
that I was saying virtually ALL electronic components are capable of
being PCB mounted so any component supplier has "PCB components".
However, some suppliers specialise in certain types of components only
and not others. Without knowing the family or type of components you
want then we can't answer you. Further to that we don't know where you
are located and we don't know whether you meant "suppliers in your
area" or suppliers "anywhere in the world".

If you want the largest suppliers capable of supplying almost any
components or tool used in electronics in the US then perhaps Mouser,
and in Canada Allied, and in the UK/Australia/NZ then RS Components.
There are literally thousands of other suppliers which may or may not
suit your needs but we can't exactly guess what you are looking for.

How do you think all the current electronics engineers/techs managed
to discover the intricacies of electronics and where to get components
when they were newbies? They didn't have the internet where they could
absolve all care and the requirement for research off their own bat by
simply jumping onto a NG and typing some inane question. They had to
buy electronics magazines and books and read as much as they could to
get the basics and then go to tech school to learn more. Only when
they felt a bit confident of their knowledge were they then prepared
to ask a question or two of a more experienced electronics boffin or
instructor face to face at a technical/trade school. The internet has
made it too simple and too convenient for anyone without even the
basic knowledge of what electronics components are and how they work
to take to the keyboard and try to get detailed instructions as to how
to buy, prototype and construct a project - often one of such
complexity that only a technician with many years of technical
experience and accumulated knowledge would attempt.

Every post that I make results in some smartass worthless post. I already
admitted that I'm new at this what else do you want? If I knew all this
stuff then I wouldn't be asking for help. I'm trying to learn and if you
are unwilling to teach then I would suggest you not reply to my posts. I
belong and lurk at many other boards and they don't (for the most part) have
these worthless responses. Those newsgroups help each other and are
understanding and helpful to the newbies. This group just keeps knocking
the newbie down. I get it, I'm new and you are all electronic gods. "How
dare the little old newbie ask a question, hes not worthy to talk to the
likes of me."

Since your posts, by your own admission, seem to attract what you call
"smartass worthless posts" perhaps you should be asking yourself the
question "just who is marching out of step?" And, if you are honest,
you might even come to the conclusion that it could be yourself and
not the people who are responding to your posts.

Firstly, I was trying to help on your specific problem, but suddenly
you chucked a wobbly and steered off at a tangent in the middle of the
thread and stated asking a general question about component suppliers.

As John Fields has inferred, since you admit you are a newbie then
perhaps you should not be posting in this NG, but more appropriately
in science.electronics.basics.

I don't need this. I'll just stay with asking the electical engineer at
work. I was trying not to bother him but when I started get worthless
responses I went ahead and asked and he, unlike the people here, was more
than willing to help, even with his super busy schedule. He even gave me an
old breadboard that he had. Today I asked about sources for "PCB components
for making my first board" and he gave me a two huge catalogs. He didn't
give me shit about not asking a specific question. Its so nice to find
someone willing to help I wish I could have found it here.

Your query about "PCB components" is so general that you might have
dispensed with the "PCB" and simply asked about "components". As I
have said, virtually ALL common electronic components can be PCB
mounted, so you weren't helping yourself at all with such an inane
question. Now if you had asked about SMD components (since these can
only be mounted on PCB's) then it would have made more sense but even
then not very specific. You could have expanded a bit more by
specifying such things as resistors, capacitors or active components
such as discrete semiconductors or IC's. Now each of these groupings
contains subgroups pertaining to more specialised applications and
uses and it is impossible to provide an answer to your query without
that information.

The reason the engineer at work simply gave you the catalogue to look
at was that since you didn't exactly know what you were looking for
then perhaps by researching the catalogue you would be able to ask
about specific components you were interested in. It would have been
impossible for him to spend the time answering your questions which
may have been pointless before you looked at the catalogue. Then
before asking on the NG you should have used Google and located
suppliers local to your area where you could at least look at the
components even if you didn't want to buy. Thats what I and many other
newbies had to do when we were learning.

Ross, I do appreciate the links you provided. They helped and I did
understand serial vs. parallel but at least the link verified that. You
were the closest to being helpful.

As for the rest of the group, its just not worth it. You people are so
negative and unhelpful that its really sad. I'm unsubscribing from this
"I'm better than you" group. If anyone wants to be friendly and actually
helpful you may contact me directly. I'm the most friendly guy you'll ever
meet when I not being ridiculed!

"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:bcoeo2pvf71o4vklqlqjlu3l5pu45hcj42@4ax.com...
On Tue, 19 Dec 2006 03:00:00 GMT, "SBFan2000"
glenn@glenngriffithNOSPAM.com> wrote:

Anyone got a good supplier for PCB components! I'm looking at a couple
but
was wondering what others are using?


I am sorry to have to say this but when you ask such an open ended,
non-specific question such as this I wonder how you managed to get
this far on the NG without somebody jumping on you. I mean - "PCB
components" have been around even before the PCB was first devised.

Thats interesting, the "PCB component" was around BEFORE the PCB! That must
have been hard for people having all these "PCB components" and not having
anywhere to put them or for that matter even knowing what a PCB was. I
would suggest that they may not have been called "PCB components" if the PCB
didn't yet exist.

YOu haven't been listening. Components such as axial resistors and
capacitors have been around since the dawn of modern electronics. They
weren't initially intended to be mounted on PCB's because those
mounting methods hadn't yet been devised. Nevertheless, when the PCB
was subsequently introduced, those very same components were able to
be mounted on the PCB. The ONLY components which might properly be
called "PCB Components" are those intended for surface mounting, since
it is impracticable to mount them on anything but a PCB.

Virtually any passive component (resistor, capacitor, inductor,
transformer etc) can be PCB mounted.

Thereby making them a "PCB component" and a subject of my request. Perhaps
you could have suggested a place to purchase them.

Sure, but where are you located? Am I supposed to just guess? For
example I live in Perth, Australia but it probably doesn't help you
much if I tell you Altronics http://www.altronics.com.au/ or Jaycar
http://www.jaycar.com.au/ or RS Components http://www.rsaustralia.com/

RS do however have distributors inthe US but there are so many to
choose from so I can't help more than this.

Before PCB's, components were
mounted on stripboard or bare phenolic or fibreglass board with
soldered wire links. The very same components can also be mounted on
PCB's.

If you want help then you have to be more specific because there are a
million places which anyone who has even the vaguest interest in
electronics will know of. Why don't you just try Googling for
electronic components of the type you need?

I have! Imagine that! I've found most of what I need but would rather
place one or two orders from large suppliers instead of 10-15 little guys!
Hence the question.

You weren't specific enough.

YOu need to think more logically before putting fingers to the
keyboard.

And you need to stick to the question asked or ask a polite counter
question.

My reply certainly was critical of you but you didn't pose the
question in a way which said you wanted to buy all your components
from one supplier. Heck, even large suppliers can't supply everything
needed for a specific project. That's why a project design team will
usually have a person with precise and specific knowledge of nothing
else but components and where to source them. As many as 6 or more
suppliers may be needed to source all the items needed in a design.
The engineers design the stuff and then tell the components man what
they need and he has to go out and find it at the same time as
considering second and even third sourcing in case one supplier dries
up or goes bust or one manufacturer stops producing.

EVERYONE HAVE A MERRY CHRISTMAS!

And the same to you.

 

[Marcus Redd]

"John Fields" <jfields@austininstruments.com> wrote in message
news:ro9ho2th94t7s8f39kmi2j3hp4kqe01po4@4ax.com...

On Tue, 19 Dec 2006 22:29:54 GMT, "SBFan2000"

Well that was a waste of your time, John. He's unsubscribed, didn't you spot
that bit?

 

[John Fields]

On Wed, 20 Dec 2006 09:21:36 -0000, "Marcus Redd" <read@it.com>
wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:ro9ho2th94t7s8f39kmi2j3hp4kqe01po4@4ax.com...
On Tue, 19 Dec 2006 22:29:54 GMT, "SBFan2000"

Well that was a waste of your time, John.

---
That's OK, things are pretty slow around here.
---

He's unsubscribed, didn't you spot that bit?

---
Yup, but the deed doesn't always follow the word...


--
JF

 

[jasen]

On 2006-12-19, SBFan2000 <glenn@glenngriffithNOSPAM.com> wrote:

Anyone got a good supplier for PCB components! I'm looking at a couple but
was wondering what others are using?

PCB components? you mean like fibreglass, resin, and copper sheet?

I don't think any of the posters here who claim to "make their own" go to
that extreme!



Bye.
Jasen