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Does anyone know of a digital thermostat that can power electric heaters? But... [read on]
Does anyone know of a digital thermostat that can simply call for heat if the temp falls below a given set point, and stops calling when the temp is at or above the set point - to a resolution of 0.1C? This is for electrical heating control, so I don't want it to minimise the number of power cycles - it can come on and off as often as it needs. Most digistats such as Drayton try to minimise the number of power cycles, as you'd want if it was controlling a boiler, but for electric heat this shouldn't matter. I'm want a simple "call for heat if below the exact set point, otherwise don't call for heat". Any ideas?
Comments
11 years ago
Do you want a readout ? or just control to a resolution of 0.1 C. Where are you ? In the UK, you'd get what you need from Maplin.
Steve
Answer 11 years ago
All answers noted, thanks. It's for controlling a normal domestic electric heater with a fan - 2KW. A readout would be good. I am already successfully using a Drayton Digistat 2+ for this, but it seems to have a fairly wide "temperature band" (sorry, don't know the proper phrase) - i.e. for a set point of 20.0, the actual temp can range from at least 19.0 to 21.0, sometimes worse - I'd like it controlled a bit more accurately if possible. Not end of the world, but I'm just being a geek I guess. Thanks for answers anyway, folks.
11 years ago
> for electric heat this shouldn't matter.
. Unless you are cycling the heater elements at greater than ~5 Hz, you will have high startup/in-rush currents. You will use much more current than is necessary.
. The high startup current also decreases the life of the element and other components that control the element.
. It matters.
Answer 11 years ago
Sounds to me like he's after phase control, if he wants real sensitivity, rather than zero crossing/burst mode control. A lot depends on the load he is heating I think.