A relay resistor board to turn on two heat pumps and a second set of 3 heat pumps at the same time.
Currently I have five thermistors in two hot water tanks of each of the five heat pumps. 2 thermistor in one tank and 3 thermistors in a second tank
Wanted Leaving one thermistor in each tank only connected to two inputs in a Relay board to replicate the exact resistance of each of the two thermistors with output to Five heat pumps (in sets of two and three heat pumps.)
I need the hardware- Board built and delivery to Australia thanks
The hot water is used for a Hydronic heating system in my house as well and normal hot water supply. The five Thermistors are not turning on all five Heat pumps on together and often one or two heat pumps tries to heat all the hot water used for heating in winter. The one or two on runs for many hours or continually. This might be due to the hot water being drawn by the heating system only slowly reducing the tanks temperature with the one or two heat pumps running almost being enough to maintain a hot water level that is not triggering the other thermistors in the hot water tanks. If they all activate at once they can heat the water in less than 45 minutes once or twice a day.
Discrete value would be fine. As the KΩ of 4 is the trigger to turn on the heat pumps. The Off function is via other thermistors on the heat pumps hot water outlet back to the tanks. As long as the Discrete value retuned to ≥ KΩ 3.6 on the output once the tank thermistor was at ≥ KΩ 3.6.
It would be fine to have only two values in the output KΩ 3.6 and KΩ of 4.5 with the 4.5 being the on trigger.
Multimeter on the tank thermistors. It shows 1.7 to 1.78volts
The tank thermistor is used to turn the heat pump on once the Tank Thermistor ≤ 45 oC . The Thermistor resistance KΩ 5.3 is 40degrees and 3.6 is 50 degrees. I assume KΩ of 4 is the trigger to turn on the heat pumps.
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Hi dear, we can chat regarding the details of your project Relevant Skills and Experience Electrical Engineer Proposed Milestones $600 AUD - Thermistor
hello, i am from shenzhen, china. i can do it for you. please PM me . and share more details to me Relevant Skills and Experience Schematic and PCb. Design Proposed Milestones $277 AUD - one time
Expertise in analog and digital electronics with five years of industrial experience in this field. I can provide you assistance in completing your task. We can discuss further details in the message Regards