Thanks CBank. What I have at the moment is a collection of devices with various software installed, most of them are conceptually good but they have all become unreliable after a time and are on the shelf. Some of them have a cooling function also but this is not needed where I am. Right now I have nothing that works properly, luckily this season I am not raising any cells.
The device you show sounds good, possibly, but it does not say if it's a PID controller, so let me first explain what a PID controller is, as against a straight on / off controller.
A standard on / off controller waits till the temperature reaches a set level, then turns off power to the heating device. It then waits till temperature falls to some level, and then turns the power back on. The problem with this is there has to be temperature swings for it to work. This is also exaggerated, because when it turns on power to the heating element, it waits for the temperature to get to a certain point, then turns off. But by this time the heating element is hot, and the incubator continues getting hotter until the element has lost all it's heat so the swing is even greater.
A PID controller is different. PID controllers have software that when it is first turned on, it sees how fast the incubator warms up. Based on this it calculates when the incubator will reach the desired temperature, and turns the heating element off before the temperature gets there, allowing the element to cool. The PID controller then sends pulses to the heating element, bringing the incubator closer to the desired temperature, the pulses get shorter and less frequent as the temperature gets nearer, so once the temperature is reached there is no overshoot. A good PID controller will learn what is needed to maintain the temperature, and send pulses to the heating element to maintain temperature almost exactly. A temperature genuinely within 0.1 of a degree can often be maintained by a good PID controller, but with a normal controller such accuracy is impossible, even if the device claims to ba able to do it.
Some of the ones I have had, the software has been excellent and worked well, but eventually the hardware has fallen over. Seems the market is dominated by cheapo Chinese manufactured stuff, I have not been able to figure out what is actually a quality brand.
All I need is something to accurately regulate heating, and send power to a humidity generator if needed. I did not need cooling, or humidity reduction. When I had one that was working accurately, the quality of the queens was superb. I would like to be able to set one up again, but want reliable equipment, not something I'm worried about.
The device you linked MIGHT be able to do that, but it does not actually state that it is a PID controller, which makes me suspect it probably isn't. My guess is a straight on / off controller would be OK for brewing. On the plus side it does have a solid state relay, this is a must for a PID controller because of the frequent pulsing and on / off cycles.