PID Temperature Controller, Digital Display REX-C100 Temperature Controllers Box with Solid State Relay SSR 40DA and K Thermocouple Probe, Universal 100-240V (PID+40DA SSR+Heat Sink+K Sensor)

Great value for that price. Works all well. But its not a PID controller as integral and differential control paramaters are not there. Only proportional parameter can be adjusted, which is fine for a furnace with typical slow on/off response. Definitely worth the money.

Directions are a nightmare but I found a wiring diagram online. Wired for 240 to a hot water element. Turns on with the output light on but there's no power going to the SSR. Tried researching the problem via Google but no luck. Going to order a different more user friendly option.*Got the new one. Only swapped the PID controler and my element fired right up.

Easy to set up and simple to use.NOTE: not for heavy duty cycles.

4 stars overall, and only 2 stars for ease of use. I do not know if there is a world wide conspiracy in place to prevent users form being able to simply operate these PID units or what. I have 4 different brands and not one of them came with usable instructions. If you where in on the engineering team that designed them, you may be able to operate these to their full potential. It took 2 days, and hours of searching just to find out how to change the reading from Celsius to Fahrenheit.!I would pay an extra 20 bucks for these if they came with a comprehensible English instruction manual that covered all aspects of their operation. I do not understand why, with the thousands of different brands, styles and uses for these PIDS, that some one has not translated the instructions into proper, concise English.Now with that said. This unit -with the supplied pieces, hooked up to an open air test rig in my shop, with a heating element, poorly mounted thermocouple, on a bench with a hot air furnace coming on and off. it was able to maintain temperature within 3 degrees F after running the auto tune feature. Pretty impressive results for a test in poor conditions.This Model is a Rex-C100, branded good-i. There are a lot of rex -C100 out there with different brands on them- one of my others is a differently branded Rex-C100 and its operation (programming) is different than this one, so don't buy the same model expecting it to work like another one of the same model.Again, this does work very well, once you get around to figuring out how to make it do what its supposed to do. Good luck!

Bought the box so it was plug and play. Equipment it's hooked up to is 240v and rate for 26 amps i have the properly rated K probe for 1300C. Only need to run my equipment to 640C. Well within the "advertised" specs. Relay melted and I realized it doesn't have a heat sink like the listing says. Too bad because it was working great