Time delay using relays

N

Nikki

Guest
Hi guys I have a small problem Im hoping someone can help me with.
I have magnetic switches on all my windows (open window and circuit
closes). Each is wired too two relays the first relay is turned on by
the magnetic switch and because of the way they are wired the first
turns on the second and then the second stays on and turns the first
off. Now on the first relay on a set of normally open contacts this is
wired to a keyboard of a computer so each magnetic switch would say type
one letter in notepad or for me I have a program that assigns a key to a
wav file so when say the kitchen window is open a wav file plays telling
me that window is open.
Now my problem. The first relay that is wired to the keyboard is only
on for less than a second and is in most cases not enough time for the
computer to realize that say the letter "M" is pushed. How can I either
delay relay one going off or some other way of doing this. I came by
the relays free I need 24 circuits like this one.

I hope I have explained it good enough any help would be appreciated
Thanks
Nikki
 
Nikki wrote:
Hi guys I have a small problem Im hoping someone can help me with.
I have magnetic switches on all my windows (open window and circuit
closes). Each is wired too two relays the first relay is turned on by
the magnetic switch and because of the way they are wired the first
turns on the second and then the second stays on and turns the first
off. Now on the first relay on a set of normally open contacts this is
wired to a keyboard of a computer so each magnetic switch would say type
one letter in notepad or for me I have a program that assigns a key to a
wav file so when say the kitchen window is open a wav file plays telling
me that window is open.
Now my problem. The first relay that is wired to the keyboard is only
on for less than a second and is in most cases not enough time for the
computer to realize that say the letter "M" is pushed. How can I either
delay relay one going off or some other way of doing this. I came by
the relays free I need 24 circuits like this one.

I hope I have explained it good enough any help would be appreciated
Thanks
Nikki
I can send or post My wiring diagram for the two relays if you tell me where
Click to expand...
Nikki
 
Nikki wrote:
Nikki wrote:
Hi guys I have a small problem Im hoping someone can help me with.
I have magnetic switches on all my windows (open window and circuit
closes). Each is wired too two relays the first relay is turned on by
the magnetic switch and because of the way they are wired the first
turns on the second and then the second stays on and turns the first
off. Now on the first relay on a set of normally open contacts this is
wired to a keyboard of a computer so each magnetic switch would say type
one letter in notepad or for me I have a program that assigns a key to a
wav file so when say the kitchen window is open a wav file plays telling
me that window is open.
Now my problem. The first relay that is wired to the keyboard is only
on for less than a second and is in most cases not enough time for the
computer to realize that say the letter "M" is pushed. How can I either
delay relay one going off or some other way of doing this. I came by
the relays free I need 24 circuits like this one.

I hope I have explained it good enough any help would be appreciated
Thanks
Nikki
I can send or post My wiring diagram for the two relays if you tell me where
Nikki
Click to expand...
You can post it to news:alt.binaries.schematics.electronic by
attaching it as a GIF, JPEG, or other common image file. Then, post a
message here giving the name of the post. If you try to post a binary
file here, most people will never see it.

--
Link to my "Computers for disabled Veterans" project website deleted
after threats were telephoned to my church.

Michael A. Terrell
Central Florida
 
Nikki wrote:
Hi guys I have a small problem Im hoping someone can help me with.
I have magnetic switches on all my windows (open window and circuit
closes). Each is wired too two relays the first relay is turned on by
the magnetic switch and because of the way they are wired the first
turns on the second and then the second stays on and turns the first
off. Now on the first relay on a set of normally open contacts this is
wired to a keyboard of a computer so each magnetic switch would say type
one letter in notepad or for me I have a program that assigns a key to a
wav file so when say the kitchen window is open a wav file plays telling
me that window is open.
Now my problem. The first relay that is wired to the keyboard is only
on for less than a second and is in most cases not enough time for the
computer to realize that say the letter "M" is pushed. How can I either
delay relay one going off or some other way of doing this. I came by
the relays free I need 24 circuits like this one.

I hope I have explained it good enough any help would be appreciated
Thanks
Nikki
Click to expand...
This circuit delays the turn on of Relay2 (RY2), which means
that Relay1 will stay energized for the delay time. When the
magnetic switch closes, Relay1 (RY1) energizes. Roughly 1-10
seconds later (depending on the setting of the delay), RY2
turns on. When RY2 turns on, RY1 turns off.
Assuming 12 volt relays:

+12V----+-----+-----+------+-------+-----+
| | | | | |
[D1] [RY1] | | [D2] [RY2]
| | | | | |
+-----+ [R1] [POT] +-----+
| | | |
| | | c/
[R2C] | +---[ZD1]---| TIP110
| | +| e\
| | [C1] |
| | | |
Gnd--MagSw----+-----+------+-------------+


R2C is the normally closed contact of R2
ZD1 is a 6 volt zener diode.
POT is a 50K potentiometer configured as a variable resistor.
(The center pin and one of the end pins are shorted togther)
C1 is 100 uF, 16 V electrolytic
D1, D2 - 1N4002 diodes
R1 is 10K
The transistor is a TIP110

Adjust the pot for the length of time you need RY1 to stay
energized. The banded end of the zener diode is on the left,
the other diodes (D1,D2) have the band at the top. The magnetic
switch can be in either the +12 volt lead or the ground lead.

Ed
 
ehsjr wrote:
Nikki wrote:

Hi guys I have a small problem Im hoping someone can help me with.
I have magnetic switches on all my windows (open window and circuit
closes). Each is wired too two relays the first relay is turned on by
the magnetic switch and because of the way they are wired the first
turns on the second and then the second stays on and turns the first
off. Now on the first relay on a set of normally open contacts this is
wired to a keyboard of a computer so each magnetic switch would say
type one letter in notepad or for me I have a program that assigns a
key to a wav file so when say the kitchen window is open a wav file
plays telling me that window is open.
Now my problem. The first relay that is wired to the keyboard is only
on for less than a second and is in most cases not enough time for the
computer to realize that say the letter "M" is pushed. How can I
either delay relay one going off or some other way of doing this. I
came by the relays free I need 24 circuits like this one.

I hope I have explained it good enough any help would be appreciated
Thanks
Nikki


This circuit delays the turn on of Relay2 (RY2), which means
that Relay1 will stay energized for the delay time. When the
magnetic switch closes, Relay1 (RY1) energizes. Roughly 1-10
seconds later (depending on the setting of the delay), RY2
turns on. When RY2 turns on, RY1 turns off.
Assuming 12 volt relays:

+12V----+-----+-----+------+-------+-----+
| | | | | |
[D1] [RY1] | | [D2] [RY2]
| | | | | |
+-----+ [R1] [POT] +-----+
| | | |
| | | c/
[R2C] | +---[ZD1]---| TIP110
| | +| e\
| | [C1] |
| | | |
Gnd--MagSw----+-----+------+-------------+


R2C is the normally closed contact of R2
ZD1 is a 6 volt zener diode.
POT is a 50K potentiometer configured as a variable resistor.
(The center pin and one of the end pins are shorted togther)
C1 is 100 uF, 16 V electrolytic
D1, D2 - 1N4002 diodes
R1 is 10K
The transistor is a TIP110

Adjust the pot for the length of time you need RY1 to stay
energized. The banded end of the zener diode is on the left,
the other diodes (D1,D2) have the band at the top. The magnetic
switch can be in either the +12 volt lead or the ground lead.

Ed
Thanks guys I have found that If I use a 470uf cap across the relay That
Click to expand...
holds the relay in long enough.
Does anyone have a good (cheap) supplier I need 30 of these
Nikki
 
Nikki wrote:
ehsjr wrote:

Nikki wrote:

Hi guys I have a small problem Im hoping someone can help me with.
I have magnetic switches on all my windows (open window and circuit
closes). Each is wired too two relays the first relay is turned on
by the magnetic switch and because of the way they are wired the
first turns on the second and then the second stays on and turns the
first off. Now on the first relay on a set of normally open contacts
this is wired to a keyboard of a computer so each magnetic switch
would say type one letter in notepad or for me I have a program that
assigns a key to a wav file so when say the kitchen window is open a
wav file plays telling me that window is open.
Now my problem. The first relay that is wired to the keyboard is
only on for less than a second and is in most cases not enough time
for the computer to realize that say the letter "M" is pushed. How
can I either delay relay one going off or some other way of doing
this. I came by the relays free I need 24 circuits like this one.

I hope I have explained it good enough any help would be appreciated
Thanks
Nikki



This circuit delays the turn on of Relay2 (RY2), which means
that Relay1 will stay energized for the delay time. When the
magnetic switch closes, Relay1 (RY1) energizes. Roughly 1-10
seconds later (depending on the setting of the delay), RY2
turns on. When RY2 turns on, RY1 turns off.
Assuming 12 volt relays:

+12V----+-----+-----+------+-------+-----+
| | | | | |
[D1] [RY1] | | [D2] [RY2]
| | | | | |
+-----+ [R1] [POT] +-----+
| | | |
| | | c/
[R2C] | +---[ZD1]---| TIP110
| | +| e\
| | [C1] |
| | | |
Gnd--MagSw----+-----+------+-------------+


R2C is the normally closed contact of R2
ZD1 is a 6 volt zener diode.
POT is a 50K potentiometer configured as a variable resistor.
(The center pin and one of the end pins are shorted togther)
C1 is 100 uF, 16 V electrolytic
D1, D2 - 1N4002 diodes
R1 is 10K
The transistor is a TIP110

Adjust the pot for the length of time you need RY1 to stay
energized. The banded end of the zener diode is on the left,
the other diodes (D1,D2) have the band at the top. The magnetic
switch can be in either the +12 volt lead or the ground lead.

Ed

Thanks guys I have found that If I use a 470uf cap across the relay That
holds the relay in long enough.
Does anyone have a good (cheap) supplier I need 30 of these
Nikki
I need a little help with the cap Im not sure what type it is I have
Click to expand...
posted a picture of it at
news:alt.binaries.schematics.electronic
If someone could tell me what type it is I can look around for a good
price on some
Thanks again
Nikki
 
Thanks guys I have found that If I use a 470uf cap across the relay That
holds the relay in long enough.
Does anyone have a good (cheap) supplier I need 30 of these
Nikki
Click to expand...
You're going to burn up your mag switches doing that- try tack soldering
two additional components on top of the capacitor:
View in a fixed-width font such as Courier.


.--------->>---------------------------.
| |
| |
| |
| |
| +-----+-----------+
| | _|_ |
| V+ 10ohm/ / \ |
--- 1W \ --- |
- | |1N4001 K
| - +-----+ K relay
| + | K
| -+- K
| --- |
| - |470u |
| | |
| +-----------------+
| |
| |
| |
| / |
.--->>----o o----->>------------------.
mag sw
 
Nikki wrote:

Thanks guys I have found that If I use a 470uf cap across the relay That
holds the relay in long enough.
Does anyone have a good (cheap) supplier I need 30 of these
Nikki
Click to expand...
Great!

Mouser part #: 140-XRL25V470 16 cents each in lots of 10
http://www.mouser.com/

As Fred mentioned, I'd be concerned with burning up your
mag switches.

Ed
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top