Circuit to indicate failure of a heating element

I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

I'd like to have an LED connected to each circuit, to warn me when the
element has failed.

Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.

(Power supply is UK mains - 230V, 50Hz AC)

 

[David L. Jones]

ojcouzens@gmail.com wrote:

I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

I'd like to have an LED connected to each circuit, to warn me when the
element has failed.

Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.

(Power supply is UK mains - 230V, 50Hz AC)

Perhaps overkill, but you could install two Cent-a-meter type power
consumption devices on just the line supplying the heaters:
http://www.centameter.com.au/products.htm
That way you can monitor your power consumption and easily check for a
failed element remotely.

Dave.

--
---------------------------------------------
Check out my Electronics Engineering Video Blog & Podcast:
http://www.alternatezone.com/eevblog/

 

[ojc]

On 11 May, 12:55, "David L. Jones" <altz...@gmail.com> wrote:

ojcouz...@gmail.com wrote:
I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is:  one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

I'd like to have an LED connected to each circuit, to warn me when the
element has failed.

Grateful if you would tell me how.  I have a bit of electrical
experience, but next-to-no electronic.

(Power supply is UK mains - 230V, 50Hz AC)

Perhaps overkill, but you could install two Cent-a-meter type power
consumption devices on just the line supplying the heaters:http://www.centameter.com.au/products.htm
That way you can monitor your power consumption and easily check for a
failed element remotely.

Dave.

--
---------------------------------------------
Check out my Electronics Engineering Video Blog & Podcast:http://www.alternatezone.com/eevblog/

Thanks Dave, I hadn't thought of this (though I was hoping to be able
to do it with a handful of components rather than 2 x expensive pieces
of kit.
Oliver.

 

[ABLE1]

<ojcouzens@gmail.com> wrote in message
news:c0bd19c8-c289-4d83-a972-ec71a29d7409@r3g2000vbp.googlegroups.com...

I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

I'd like to have an LED connected to each circuit, to warn me when the
element has failed.

Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.

(Power supply is UK mains - 230V, 50Hz AC)

Don't know what you guys in the UK have available but this might get your
brain juices flowing.

Do a search for a device that is called here across the pond as a "Current
Sensing Relay".

You simply loop your wire lead to the heater thru the coil a couple of times
and when there is current a relay is energized. The relay can turn on a
bell or a light or what ever when the current drops out. Based on your use
you would need a time delay relay so that you would only get the signal you
wanted.

Saying it in other terms. Thermostat turns on heater and time delay. If
current flows as it should the current relay triggers and now audible or
light is lit. After a period of time the timer delay ends and all is
checked ok. Now if the heater is burned out and the T-Stat turns the
heater(which does not work) and the time delay. No current flows so the
relay does not trigger and the audible sounds or the light turns on.

If you know how to draw a "ladder logic diagram" it will help with the
wiring.

Hope that make some sense over there.

Good luck.

Les

 

[ABLE1]

"ABLE1" <royboynospam@somewhere.net> wrote in message
news:GYYNl.257869$BR.111464@en-nntp-04.dc1.easynews.com...

ojcouzens@gmail.com> wrote in message
news:c0bd19c8-c289-4d83-a972-ec71a29d7409@r3g2000vbp.googlegroups.com...
I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

I'd like to have an LED connected to each circuit, to warn me when the
element has failed.

Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.

(Power supply is UK mains - 230V, 50Hz AC)

Don't know what you guys in the UK have available but this might get your
brain juices flowing.

Do a search for a device that is called here across the pond as a "Current
Sensing Relay".

You simply loop your wire lead to the heater thru the coil a couple of
times and when there is current a relay is energized. The relay can turn
on a bell or a light or what ever when the current drops out. Based on
your use you would need a time delay relay so that you would only get the
signal you wanted.

Saying it in other terms. Thermostat turns on heater and time delay. If
current flows as it should the current relay triggers and now audible or
light is lit. After a period of time the timer delay ends and all is
checked ok. Now if the heater is burned out and the T-Stat turns the
heater(which does not work) and the time delay. No current flows so the
relay does not trigger and the audible sounds or the light turns on.

If you know how to draw a "ladder logic diagram" it will help with the
wiring.

Hope that make some sense over there.

Good luck.

Les

Much like this one.

http://www.crmagnetics.com/newprod/ProductView.asp?ProdName=CR4395

 

[Baron]

ojcouzens@gmail.com wrote:

I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

I'd like to have an LED connected to each circuit, to warn me when the
element has failed.

Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.

(Power supply is UK mains - 230V, 50Hz AC)

You could probably do it with a ferrite toroid, some fine enamelled
wire, a diode and a LED. You would wind say 100 turns of wire on the
toroid connect the led and diode in parallel, connect the pair across
the toroid. Feed one leg of the heater through the core. You may need
one or two turns. The diode is only there to prevent reverse voltage
damaging the LED. You will need to play around a bit to get the turns
ratio right, but as long as current flows through the heater the LED
will glow.

--
Best Regards:
Baron.

 

[George Jetson]

"Baron" <baron.nospam@linuxmaniac.nospam.net> wrote in message
news:gu9rg3$qu4$1@news.motzarella.org...

ojcouzens@gmail.com wrote:

I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

I'd like to have an LED connected to each circuit, to warn me when the
element has failed.

Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.

(Power supply is UK mains - 230V, 50Hz AC)

You could probably do it with a ferrite toroid, some fine enamelled
wire, a diode and a LED. You would wind say 100 turns of wire on the
toroid connect the led and diode in parallel, connect the pair across
the toroid. Feed one leg of the heater through the core. You may need
one or two turns. The diode is only there to prevent reverse voltage
damaging the LED. You will need to play around a bit to get the turns
ratio right, but as long as current flows through the heater the LED
will glow.

--
Best Regards:
Baron.
Maybe just an incandecant lamp across each heating element, color to taste.

 

[ABLE1]

"George Jetson" <GJetson@yahoo.com> wrote in message
newsR2Ol.22141$as4.10718@nlpi069.nbdc.sbc.com...

"Baron" <baron.nospam@linuxmaniac.nospam.net> wrote in message
news:gu9rg3$qu4$1@news.motzarella.org...
ojcouzens@gmail.com wrote:

I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

I'd like to have an LED connected to each circuit, to warn me when the
element has failed.

Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.

(Power supply is UK mains - 230V, 50Hz AC)

You could probably do it with a ferrite toroid, some fine enamelled
wire, a diode and a LED. You would wind say 100 turns of wire on the
toroid connect the led and diode in parallel, connect the pair across
the toroid. Feed one leg of the heater through the core. You may need
one or two turns. The diode is only there to prevent reverse voltage
damaging the LED. You will need to play around a bit to get the turns
ratio right, but as long as current flows through the heater the LED
will glow.

--
Best Regards:
Baron.
Maybe just an incandecant lamp across each heating element, color to
taste.

Would that not only just tell that power is available at the connection????
He needs to know if current is flowing thru the heating element.

 

[Michael A. Terrell]

ABLE1 wrote:

"George Jetson" <GJetson@yahoo.com> wrote in message

Maybe just an incandecant lamp across each heating element, color to
taste.

Would that not only just tell that power is available at the connection????
He needs to know if current is flowing thru the heating element.

Put them across each thermostat. Then they will light when the
switch is open.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

http://www.flickr.com/photos/materrell/

 

[Jasen Betts]

On 2009-05-12, Michael A. Terrell <mike.terrell@earthlink.net> wrote:

ABLE1 wrote:

"George Jetson" <GJetson@yahoo.com> wrote in message

Maybe just an incandecant lamp across each heating element, color to
taste.

Would that not only just tell that power is available at the connection????
He needs to know if current is flowing thru the heating element.


Put them across each thermostat. Then they will light when the
switch is open.

and the light will be out when the thermostat is on, the element is broken,
or the ripple-control is off.

that's going to be confusing.

 

[Jasen Betts]

On 2009-05-11, ojcouzens@gmail.com <ojcouzens@gmail.com> wrote:

I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

I'd like to have an LED connected to each circuit, to warn me when the
element has failed.

Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.

(Power supply is UK mains - 230V, 50Hz AC)

it's not a simple problem. water heating is often on a fairly complex
circuit
(ripple-control, meter, circuit breakers, switch, thermostat, heater)

also the heating element has two failure modes, one of which will blow
the breaker and the other won't.

also in normal use the boost element is only runs when the tank is
almost all cold.

 

[Michael A. Terrell]

Jasen Betts wrote:

On 2009-05-12, Michael A. Terrell <mike.terrell@earthlink.net> wrote:
ABLE1 wrote:

"George Jetson" <GJetson@yahoo.com> wrote in message

Maybe just an incandecant lamp across each heating element, color to
taste.

Would that not only just tell that power is available at the connection????
He needs to know if current is flowing thru the heating element.


Put them across each thermostat. Then they will light when the
switch is open.

and the light will be out when the thermostat is on, the element is broken,
or the ripple-control is off.

that's going to be confusing.

Only to simple minds.

I used a similar design to monitor tower lights between two sites.
The indicator at the manned site was light all day, and only went off,
when all tower lights were on, including the flashing beacons. The FCC
approved the design, along with the FAA.

Just like those tower lamps, the heating elements cycle on & off. If
the indicators don't flash, you have problems.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

http://www.flickr.com/photos/materrell/

 

[whit3rd]

On May 11, 3:29 am, ojcouz...@gmail.com wrote:

I have a water tank with with 2 x 5kW heating elements (on separate
supplies).

Problem is:  one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?

If you can reach the contacts, you can (1) measure voltage across the
heater, (2) connect (just for a second) a jumper across the
thermostat, (3) have an associate (or a remote TV camera)
monitor the power meter for the house.

If the heater has low voltage, that means its thermostat is OFF.
Connect the jumper then, and if the spark doesn't convince
you that it's heating, the confederate watching the meter can
tell you that it spun faster for those few seconds.
The same will work with clamp-type AC ammeters.

 

[amdx]

<ojcouzens@gmail.com> wrote in message
news:c0bd19c8-c289-4d83-a972-ec71a29d7409@r3g2000vbp.googlegroups.com...

I have a water tank with with 2 x 5kW heating elements (on separate
supplies).
Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?
I'd like to have an LED connected to each circuit, to warn me when the
element has failed.
Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.
(Power supply is UK mains - 230V, 50Hz AC)

I think I have a circuit that will do what you ask, it still needs a few
tweaks, use it at your own risk.
If anyone on the group has any input on the circuit I'd like to hear it.
Also please go over the logic
and see if you think it will work.
http://i395.photobucket.com/albums/pp37/Qmavam/HeatingelementsensorLightJPG.jpg
Mike

 

[amdx]

"amdx" <amdx@knology.net> wrote in message
news:eeca7$4a0b7847$18d6b40c$27179@KNOLOGY.NET...

ojcouzens@gmail.com> wrote in message
news:c0bd19c8-c289-4d83-a972-ec71a29d7409@r3g2000vbp.googlegroups.com...
I have a water tank with with 2 x 5kW heating elements (on separate
supplies).
Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?
I'd like to have an LED connected to each circuit, to warn me when the
element has failed.
Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.
(Power supply is UK mains - 230V, 50Hz AC)

I think I have a circuit that will do what you ask, it still needs a few
tweaks, use it at your own risk.
If anyone on the group has any input on the circuit I'd like to hear it.
Also please go over the logic
and see if you think it will work.
http://i395.photobucket.com/albums/pp37/Qmavam/HeatingelementsensorLightJPG.jpg
Mike
Here I've added a couple extra labels,

http://s395.photobucket.com/albums/pp37/Qmavam/?action=view&current=HeatingelementsensorLightJPG.jpg

 

[Jasen Betts]

On 2009-05-14, amdx <amdx@knology.net> wrote:

ojcouzens@gmail.com> wrote in message
news:c0bd19c8-c289-4d83-a972-ec71a29d7409@r3g2000vbp.googlegroups.com...
I have a water tank with with 2 x 5kW heating elements (on separate
supplies).
Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?
I'd like to have an LED connected to each circuit, to warn me when the
element has failed.
Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.
(Power supply is UK mains - 230V, 50Hz AC)

I think I have a circuit that will do what you ask, it still needs a few
tweaks, use it at your own risk.
If anyone on the group has any input on the circuit I'd like to hear it.
Also please go over the logic
and see if you think it will work.
http://i395.photobucket.com/albums/pp37/Qmavam/HeatingelementsensorLightJPG.jpg

site seems to be down.

 

[amdx]

"Jasen Betts" <jasen@xnet.co.nz> wrote in message
news:gugm3o$9e2$1@reversiblemaps.ath.cx...

On 2009-05-14, amdx <amdx@knology.net> wrote:

ojcouzens@gmail.com> wrote in message
news:c0bd19c8-c289-4d83-a972-ec71a29d7409@r3g2000vbp.googlegroups.com...
I have a water tank with with 2 x 5kW heating elements (on separate
supplies).
Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?
I'd like to have an LED connected to each circuit, to warn me when the
element has failed.
Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.
(Power supply is UK mains - 230V, 50Hz AC)

I think I have a circuit that will do what you ask, it still needs a few
tweaks, use it at your own risk.
If anyone on the group has any input on the circuit I'd like to hear it.
Also please go over the logic
and see if you think it will work.
http://i395.photobucket.com/albums/pp37/Qmavam/HeatingelementsensorLightJPG.jpg

site seems to be down.
I just tried it, it worked, Please try again.

Mike

 

[Baron]

amdx Inscribed thus:

"Jasen Betts" <jasen@xnet.co.nz> wrote in message
news:gugm3o$9e2$1@reversiblemaps.ath.cx...
On 2009-05-14, amdx <amdx@knology.net> wrote:

ojcouzens@gmail.com> wrote in message

news:c0bd19c8-c289-4d83-a972-ec71a29d7409@r3g2000vbp.googlegroups.com...
I have a water tank with with 2 x 5kW heating elements (on separate
supplies).
Problem is: one is probably just about enough to supply all the
hot water I usually need, so how can I tell when one has failed?
I'd like to have an LED connected to each circuit, to warn me when
the element has failed.
Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.
(Power supply is UK mains - 230V, 50Hz AC)

I think I have a circuit that will do what you ask, it still needs a
few tweaks, use it at your own risk.
If anyone on the group has any input on the circuit I'd like to hear
it. Also please go over the logic
and see if you think it will work.

http://i395.photobucket.com/albums/pp37/Qmavam/HeatingelementsensorLightJPG.jpg

site seems to be down.
I just tried it, it worked, Please try again.
Mike

It seems very complicated just for a current indicator ! Yours seems
more like a complete system.

--
Best Regards:
Baron.

 

[amdx]

"Baron" <baron.nospam@linuxmaniac.nospam.net> wrote in message
news:gugv38$s1e$1@news.motzarella.org...

amdx Inscribed thus:


"Jasen Betts" <jasen@xnet.co.nz> wrote in message
news:gugm3o$9e2$1@reversiblemaps.ath.cx...
On 2009-05-14, amdx <amdx@knology.net> wrote:

ojcouzens@gmail.com> wrote in message

news:c0bd19c8-c289-4d83-a972-ec71a29d7409@r3g2000vbp.googlegroups.com...
I have a water tank with with 2 x 5kW heating elements (on separate
supplies).
Problem is: one is probably just about enough to supply all the
hot water I usually need, so how can I tell when one has failed?
I'd like to have an LED connected to each circuit, to warn me when
the element has failed.
Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.
(Power supply is UK mains - 230V, 50Hz AC)

I think I have a circuit that will do what you ask, it still needs a
few tweaks, use it at your own risk.
If anyone on the group has any input on the circuit I'd like to hear
it. Also please go over the logic
and see if you think it will work.

http://i395.photobucket.com/albums/pp37/Qmavam/HeatingelementsensorLightJPG.jpg

site seems to be down.
I just tried it, it worked, Please try again.
Mike

It seems very complicated just for a current indicator ! Yours seems
more like a complete system.

--
Best Regards:
Baron.

The OP ask for a circuit: "to warn me when the element has failed."
This circuit will do that ( I think).
He didn't ask for a current indicator, he ask for a circuit that will
indicate
that the thermostat is on but no current is flowing.
I'm open to a simpler design that meets his need.
Mike
Also this is pretty close to all electrical and very little electronic.

 

[Jasen Betts]

On 2009-05-14, amdx <amdx@knology.net> wrote:

"Jasen Betts" <jasen@xnet.co.nz> wrote in message
news:gugm3o$9e2$1@reversiblemaps.ath.cx...
On 2009-05-14, amdx <amdx@knology.net> wrote:

ojcouzens@gmail.com> wrote in message
news:c0bd19c8-c289-4d83-a972-ec71a29d7409@r3g2000vbp.googlegroups.com...
I have a water tank with with 2 x 5kW heating elements (on separate
supplies).
Problem is: one is probably just about enough to supply all the hot
water I usually need, so how can I tell when one has failed?
I'd like to have an LED connected to each circuit, to warn me when the
element has failed.
Grateful if you would tell me how. I have a bit of electrical
experience, but next-to-no electronic.
(Power supply is UK mains - 230V, 50Hz AC)

I think I have a circuit that will do what you ask, it still needs a few
tweaks, use it at your own risk.
If anyone on the group has any input on the circuit I'd like to hear it.
Also please go over the logic
and see if you think it will work.
http://i395.photobucket.com/albums/pp37/Qmavam/HeatingelementsensorLightJPG.jpg

site seems to be down.
I just tried it, it worked, Please try again.
Mike

yeah, it's back.

it looks good. As it's safe to assume that the heating elements will
never fail while unpowered it will detect failure. even where elements
fail short-circuit and out the fuse on a load controlled circuit.

you can't power the bridge rectifier from the load controlled circuit

but if reset while the fuse on a load controlled circuit is blown it
will not re-detect that, but a relay could be added to handle that


but if the short takes out the master fuse (killing all the power to
the house) it it'll trigger it won't be obvious.