Lower AC Voltage cheap & simple?

I have a small heater that has stopped working. I think that the solid state relay is bad. I bought an electro-magnetic relay (contactor?) that I was told would work but doesn't. According to the product support person, the problem is that the circuit is 29V AC. The relay is rated at 24V +/- 10%. Is there a simple, inexpensive way such as using a resistor to drop the voltage from the 29V to 24V? I have had found a couple of solid state relays that match the one that doesn't work but they cost around $60.
Thanks for your help,
Shawn

Reading your post i suspect the problem is not with ssr or relay you bought, because relay will work at higher voltage but generate lot of heat.

Check out the other things, the fault may be there

Nandhu

The tech from the store I bought the relay from stated that most relays only have a +/- 10% on the voltage. He said that the hum from the relay that I bought was due to the relay having the wrong voltage on the input side. If I push down on the top of the relay, it makes contact and the heater works. When I turn down the thermostat, the voltage goes to zero and the relay breaks the circuit. Turn the thermostat up, and the voltage goes to 29V and the relay hums but doesn't make contact.
The thermostat circuit is pretty simple with a transformer connected to the thermostat and then to the input side of the relay. I don't know what else could be wrong?
Thanks for your input,
Shawn

hi
i understand here u have 29v A.C control side solid state relay.
u must here select relay with control voltage AC 24v and u must
add small series resistor to adjust voltage.
u hear that hum when u drive dc realy with ac voltage
or ur transformer can't drive new load
but ur solid state relay take small current in control side if u replace
with relay or contactor that my be load ur transformer.

Y don't u use an AC Relay ???

The Electromechanical Relay Hums because of the following reasons
1) AC voltage at the DC Relay coil.
2) Pulsating DC at the coil.
Use a Diode & capacitor in order to resolve the AC supply issuse..
try this if it works then u can drop some volts via Diodes or resistor in series

Thank you for your response. The measured current is .4 Amps. Do you think this will drive the contactor? What size resistor would you recommend using?

Thanks,
Shawn

whatz written on the contactor ?? whatz the coil impedence ??

eg
volts = 24DC
400Ω

i think 400ma r enough to drive small contactors.
do a simple check after connecting the contactor coil measure the voltages across it, if it is above 20v then its OK

hi
if ur heater is single phase and ur thermostat with free contact
u can use circuit like this type of triac and heat sink here depend
on the power of heater and supply voltage

I do not fully understand your problem but it sounds like:

You have a 29 volt solidstate relay that controlls something

You bought a mecahnical relay, with a coil, that is specified at 24 volts.

When you energize the relay, it does not fully close.

It sounds like your problem is either:
1) you bought a 24v AC relay, and are maybe giving it 24v DC. Maybe the rectifier circuit above will solve that

2) The source of the 29v is not capable of driving the current draw of the 24V relay, so when it is energized, the 29 volts drops to something much lower...maybe 12 volts, and that is not enough to hold the relay contacts closed. In that case, you simply have the wrong type of coil relay, you need more turns of wire on the coil. Measure the actual voltage across the relay coil when it is trying to close, and tell us what you read.

Thank you all for your comments. I measured the resistance of the relay 10.0 ohms.
Biff 44.... You have the story right but the solid state relay states 24 v on the input side.
Without the relay hooked up, the voltage on the thermostat circuit reads 29v. When hooked up and attempting to energize, it reads around 8v. If I manual push it closed, it reads 23v. These readings are all AC voltage.
When you say I need a different type with more turns, how would I differentiate when attempting to buy a different relay?


Thanks again,
Shawn