The ETD is an electronic difference thermostat for ON/OFF control

Electronic ON/OFF thermostat
For difference control between two temperatures
Adjustable start and stop difference
Operation temperature 0-60ºC
LED shows activated relay
Switch for overriding of pump

Product Range

APPLICATION
The ETD is an electronic difference thermostat for ON/OFF control of the temperature difference between the heating source and storage tank in solar heating units and other types of heat recovery plants.

FUNCTION
The thermostat is constructed for ON/OFF control of the difference between two temperatures. The built-in relay is activated as soon as the sensor temperature in the heating source exceeds the temperature in the storage tank with the ºC which has been set with the "START DIFF". The real start difference is the same as the setting of "START DIFF" + "STOP DIFF". At the same time the red light diode is on on the front of the thermostat. The relay will be activated until the temperature difference has fallen with the ºC which have been set with "STOP DIFF". Then the relay releases and the LED goes out.

By means of a switch on the front a pump can be guided to constant operation. (Switch in position ON). This function can be used for starting of unit as control of pump. This function may also be used if the solar heating unit has to be secured against priming, if there is no need for heating during a longer period of time.

TEMPERATURE SENSORS
Sensor for solar collector/the solar source is connected to clamp 8 and 9. Sensor for tank is connected to clamp 10 and 11. The sensor cable may be extended up to 50 m with separate cable. Avoid that the sensor cable is placed parallel to cables which may induce noise on the sensor cable and thus disturb the function of the ETD.

Technical data