So I have a UT130 Temperature Controller turning on and off a heater element through a SSR relay to maintain the temperature of water at a constant temperature. But the problem is that the temperature will still fluctuate making the relay go on and off continuously. I need the water to stay at the set temperature and not rise and fall around the set point. Right now, the relay turns on (and so the heater) when the temperature falls below 100 and vice versa. Is there any kind of relay that allows me to control the voltage flowing through it? As in: while heating up, as the temperature gets closer to the set point, the voltage flowing through the relay and heater decrease in some ratio (i.e. the relay doesnt turn on and shut off completely) so that the temperature doesnt rise above the set point and so hopefully gives a more stable temperature? I tried searching but cant seem to find one!