Question:Relay Action Wierd :-)
sfrjosh@me.com
Posts: 6
Hello guys,
My name is Josh, I come here hoping to further my self-education. I am very interested in electrical engineering, planning on applying to a local college for such.
So I have recently started a big project for my self, I installed my air handler, ducts, and all. The system is controlled by two Honeywell digital thermostats with 'Auto Changer' mode. So i need to install dampers that open and close when the thermostats call for heat or cool. So each thermostat has it own damper to open and close.
The thermostats send a 28v (volts) back to the air handler( Thermostats get their 28v from the air handler from the RED wire)
So I went out and bought two relays (24 volt trigger) When the Thermostats call for heat they send 28 volts to the air handler via white wire, When it calls for cool, it sends it down the green wire. I took one relay and plugged it into the white wire on the 24 volt trigger relay, it will then vibrate and it will turn the air handler on, but NO it doesn't activate the trigger.!!!!!! Hey what do you know!?
I took my multimeter and check the voltage between the 2 trigger leads and I got 6.5 volts..... ??? As I said before, everything runs fine beside triggering!!!!!!!
I went out and bought two new relays with 6 volt triggers instead, I plug that bad boy in and what do you know.......? The dang thing still didn't trip UGH! Haha
I took my meter again, check the leads, they where at 2.5 volts........
I don't know what i'm doing wrong. I tested with the multimeter between the white wire and the white wire and i get 28 volts.....WHY!!!!!???? As soon as i plug it in, it's 6.5 or 2.5 volts depending on the relay. If some one could explain to me what going on. It would be much appreciated!!
-Josh
My name is Josh, I come here hoping to further my self-education. I am very interested in electrical engineering, planning on applying to a local college for such.
So I have recently started a big project for my self, I installed my air handler, ducts, and all. The system is controlled by two Honeywell digital thermostats with 'Auto Changer' mode. So i need to install dampers that open and close when the thermostats call for heat or cool. So each thermostat has it own damper to open and close.
The thermostats send a 28v (volts) back to the air handler( Thermostats get their 28v from the air handler from the RED wire)
So I went out and bought two relays (24 volt trigger) When the Thermostats call for heat they send 28 volts to the air handler via white wire, When it calls for cool, it sends it down the green wire. I took one relay and plugged it into the white wire on the 24 volt trigger relay, it will then vibrate and it will turn the air handler on, but NO it doesn't activate the trigger.!!!!!! Hey what do you know!?
I took my multimeter and check the voltage between the 2 trigger leads and I got 6.5 volts..... ??? As I said before, everything runs fine beside triggering!!!!!!!
I went out and bought two new relays with 6 volt triggers instead, I plug that bad boy in and what do you know.......? The dang thing still didn't trip UGH! Haha
I took my meter again, check the leads, they where at 2.5 volts........
I don't know what i'm doing wrong. I tested with the multimeter between the white wire and the white wire and i get 28 volts.....WHY!!!!!???? As soon as i plug it in, it's 6.5 or 2.5 volts depending on the relay. If some one could explain to me what going on. It would be much appreciated!!
-Josh
Comments
Thermostats have always been confusing to me.
Do you know if you are dealing with AC or DC with your circuit?
I'm thinking that MAYBE your 24V relays are DC relays, Which will not work correctly with 24V AC.
Your 24V trigger terminology is not familar to me.
I'm very interested in what you find out about this.
I hope my comment helps you out.
Hello Garyg,
Thanks for stopping by, My thermostat gets it 24 volts from the transformer in the air handler ( I can go more in to detail if u need)
My Circuit is AC 99% sure
Here are my relays
NTE
ELEC INC.
R14-11A10-24
24VA10A 240vac/28vdc
( ^^ This one I get 6.5v after putting on the white wire 28 vac^^)
NTE
ELEC. INC
R14-11D10-6F
6VDC
10A 240VAC/28VDC
( ^^ This one I get 2.5v after putting on the white wire 28 vac^^)
This is a side view The relay has 2 independent of each other but still trigger by the same.
What i mean buy trigger is,The 6v relay i have to run around 6 volt through the coil ( "3rd picture" leads on left, the top and bottom)
when the coil is activated or "triggered" it act like a magnet and pull the contact pin inside ( Thing between pin 2-3 on the top right. Like this: ( - lll ) the 2 red ones lol );
Just makes the always closed circuit, open when you have what ever the "trigger" voltage is in my 2 case 6v and 24v
if any one is lost i can draw a diagram of every thing and post it
I really need to solve this issue is a week or so thanks
I usually don't do research on this type of thing BUT:
I checked you NTE R14-11A-10-24 reference.
That relay according to the Radio Shack website is 24Vac.
My approach to this situation is to connect the NTE R14-11A-10-12 relay to a reliable AC source such as a Door Bell transformer
and see if the relay behaves as you would think is should.
If the relay behaves as you believe it should, chances are, there is something in the thermostat circuit that is not allowing enough current
to flow through your relay coil to turn it on.
If you are incorrectly measuring your voltage supply - Such as, 24 vac but not to neutral , you may be mistaken about the voltages.
There are LOTS of people on this website that may have a better insite than mine.
A circuit drawing would be very valuable in assisting you with your concerns.
Thanks
Hey garyg
Thanks again.
The ac source is from the 24 volt transformer in the AH, both thermostat works right I tested them independently. Its when I plug my relay in the the 28 volt white wire that it drops to 6.5 volts
( I touch the black lead to one side of the coil and the red lead to the other side of the coil, while its running)
Here is the diagram
After looking at your diagram, I believe you are series connecting two relays.
If the red wire is 24 volt ac and you have your relay connected as shown, there is another relay
located in the Air Handler unit.
You are connecting the two relay coils together in series.
This would cause some voltage to be dropped by the relay coil in the air handler and some voltage to be dropped by your relay coil.
The end result is that Neither of the relays will operate.
I'm thinking that you will need to try to understand the relay circuit in your Air Handler.
You where right I was series connecting them. I took a 2nd transformer 110-24volt hooked as followed
Red lead from AH to one side of transformer leads and the red lead from my thermostat to the same.
Then the white lead from the AH to the other transformer lead. And the white from my thermostat to the same
Gave power to the 2nd transformer and the relay works like its so post to!!! YES.
But with this method I would have to put the g to g on the transformer and y to y as well, for the relay on their line would activate.
But I need to keep the w-g-y wires not connected so the AH know What mode to do.
So do I need a transformer for each thermostat and each g-y-w or is there a better way haha
I'll come back and post some more Idears I have if you like to read. Also can can make a diagram of above later after work.
-Josh
Ps. Sry about Smile format and spelling tryed to post quick on iPhone.
Realize that you could be delving into something that can be VERY DANGEROUS!
It would seem to me, that you still need to understand more about your Air Handler circuit before
adding your damper control circuit.