mini boxed differential thermostat solar water heating pump controller 12V 10A

This controller is designed to control 12VDC or 220VAC electric water pump in solar hot water system.
Manufacturer: Deselectra
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Item Description:

This controller is designed to control 12VDC or 220VAC electric water pump in solar hot water system.

Have outputs for 2 probes witch need to be connected to output pites of the solar panel and boiler. The differential is adjustable with trimmer.

The probes are two NTC 10K and need to be soldered to insulated copper wires min 2x0.25 thickness.

Have led indication for working pump.

The output is Normally open contact with power 20A 12V and 7A 220V.

Features and details

Technical data:
1. Voltage - 12 v DC

 Red - 12V+ 
 Black - 12V-

2. Temperature range: from 10C to 90 oC
3. Differential range form  0.3  to 50C - set with trimmer.
4. Relay Output : 7А/125V DC
                              7A/250V AC
                              20A/12V DC
Please note that output - two white wires is normally open contact - there don't have any voltage. 
Can be used with 12V or 220V pump

5. Sensors - NTC 10K not waterproof.  Need to be soldered to wire - max length 15m

Dimensions - 40x28x22 mm.

Led indication for working load.

Method of work - Whenever the Probe 2  is measured to be hotter than the Probe 1 , the output NO contact of the relay close and led come on. The output remains on until the measured temperature difference between the two sensors has fallen depending of the set differential by the trimmer.

Setting differential temperature:

The trimmer need to be at average position initially. Rotate it at left and right precisely until led go off.
In this way thermostat is set at the lowest differential temperature and is ready for work.
When you rotate it counterclockwise - increase differential temperature. Please note that trimmer is not so precise and small rotating make big change of the temperature between two sensors.  

For example - Probe 1 can be located at the output pipe of hot water boiler and Probe 2 - to Output pipe of the solar panel. The output NO contact can be used to drive 12V or 220V up to 10A water pump.
In this way - when solar panel is hotter than boiler - the pump will come on.
When Differential temperature of the two probe come equal to the set by trimmer - the relay will be deactivated.