>>What if the thermostat didnt have a relay? Would hooking it up like that be a hazard? Why do you want a relay type?



The only contollers for herps on the market that for certain do not use relays are the $120-plus proportional units. They use solid-state semiconductor relays, which have no moving parts and can be switched many times per minute w/o wearing out. These are great for heat pads, heat panels, CHE's.



You want a mechanical relay type only if you want to put the dimmer in-line with it as suggested. If just using the thermostat alone, any type is fine. Proportionals are already kind of like a dimmer and thermostat in one. They heat to setpoint and keep it there with short bursts of voltage, whereas the mechanical ON/OFF thermostats bounce around the setpoint a bit because the heater is all the way on or all the way off.



The reason you want a relay type if hooking it up in series with a dimmer is that a dimmer already uses a solid-state semiconductor switch. If the thermostat does as well, as the proportional units do, they can conflict and you get no output. Not a fire hazard, just unexpected results.



I have yet to see a herp thermostat for $50-60 that wasn't the mechanical relay type. I do not have all models at my disposal to check for you, but there is little chance of that inexpensive of a thermostat having a semiconductor relay. And if by chance it does, just do not use a dimmer in-line with it and you are fine.



I already mentioned to listen for the "click" when the thermostat switches to tell if it has a mechanical relay. Semiconductors make no sound.
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Mark

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