110V 25 ampere switch research

Question

I am looking for a solution to cycle power to a pump. Below, I am referencing the thought on this device as the 'solution'.

Situation: I have a 110V 25A (maximum draw under load) pump that is powered by an inline float valve switch. (A piggyback plug to which the pump plug plugs in.)

Work around today: Pump generally runs without issue until the 15 gallon tank is emptied but on occasion, the liquid being pumped may cause backups in the line. By unplugging the power source and plugging back in, the fluid is jarred enough to cause the pump to finish pumping the liquid out of the tank. On occasion, it may take several plug/unplugged events to finish the pumping of liquid.

Theorized 'solution': Place a solution between the switch and the pump that would initiate a 5 min run cycle. The float valve switch turning off the power before the 5 minutes is up would indicate a no issue run cycle result. If the pump runs through the 5 minute run cycle, the solution would interrupt power to the pump for 1 minute and then initiate another 5 minute run cycle. This 5 minute ON 1 minute OFF cycling of the pump would replicate the work around being performed today.

Environmental: there would be no power to the solution until the float valve switch energizes the solution so the solution would require its own power source, run on battery or once energized, just begin the 5 - 1 cycle.

Any thoughts on a solution would be most appreciated.

Answer 1

There are various solutions out there. Industrial programmable cycle timers are robust but cost a couple hundred USD. They may require an additional contactor (high-current relay) as well.

1. The timer board "Cycling or Repeat Timer 1.5-180 minutes ON-OFF 12VDC/30A Heavy Duty 110V/240VAC" uses two CD4060 monostables and an integrated relay. It has two potentiometers to set on-off times, and needs a 12V supply. The supply would be connected to the float switch. The timer relay contacts would control the pump.

2. Another timer board "DC 12V Infinite Cycle Delay Timing Timer Relay ON OFF Switch Loop Module Time" is similar to the one above, but only includes a 10A relay, so it'd need an external contactor.

3. The timer module "BN-LINK Short Period Repeat Cycle Timer 24 Hours ON OFF Controls Plug In Delay" is fully enclosed and has same adjustments as the board above, but is plug-and play, i.e. requires no additional power supply. It only supplies 15A loads, so you'd need an external 110V coil contactor to switch the pump load.

4. An NCC/Ametek Repeat Cycle Timer CKK-300-461 would do the job, with a suitable socket and an external 110V coil contactor.

5. A family of OMRON H3CR Twin Timer modules, e.f. H3CR-F8 is also suitable, with an external 110V coil contactor.