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Relay for 1HP Water Pump

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xmen_xwk

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I want to automate the water filling, and for that I'm looking for a relay that can control the water pump. I have been reading many Web pages but couldn't find a clear answer.

Here are pump specifications.

KW/HP : 0.75/1
Volts : 220 +-6%
Current : 5.8A
Cap. Run : 22.5uF 440V
RPM : 2780

Is there any relay that can be controlled by 12 or 5 VDC?

Many places I found Solid State Relays, but they leak current, need heat sink and when they die, their state stays ON?(I read that long ago). So I was thinking it would be better to have mechanical relay?
 

A solid state relay might be useful in case of a high switching frequency which won't be expected for a water pump. Most water pumps are controlled by mechanical pressure or level switches directly.

Relays with 5 or 12 V coil are available, you should go for 10 or 16 A and at least 2000 VA contact rating. Preferably the relay should be explicitly specified for single phase motor load (AC3) of 0.75 kW.

- - - Updated - - -

I see that for 0.75 kW motors, 12V coil voltage is better available than 5V. Here is a 20 A relays rated for 1.1 kW single phase motor
https://www.finder-relais.net/en/finder-relays-series-65.pdf
 
Although single pole relays are sufficient for this purpose, I suggest you use a double pole double throw relay. The price difference will be marginal. The other contact can be used to show the status of the relay (pump on/off). You must ensure in your design that the relay does not turn on/off within 5 seconds (there must be some built in time delay).
 

c_mitra said:
Although single pole relays are sufficient for this purpose, I suggest you use a double pole double throw relay. The price difference will be marginal. The other contact can be used to show the status of the relay (pump on/off). You must ensure in your design that the relay does not turn on/off within 5 seconds (there must be some built in time delay).
Click to expand...

The problem is I can't seem to find a proper relay for this purpose. Currently Easyrider83's suggestion is only looking good so far with both availability and cost.
 

Till 15A it works perfect without radiator. And require very low current to be opened.
 

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