2 Pump Timer Question

[SkipFed]

Today, I have 2 Intermatic Mechanical Timers (T104M). One runs my main pump, a Pentair WF-4 1.0 HP WF. The other drives a PB-4 booster pump for the the pool cleaner. Each pump is connected to (through the timers) to a single 2 pole 40 amp breaker, each leg supplying 115V. The booster pump is appropriately wired to not run unless the main pump is running. I'm tired of messing with these mechanical timers and am ready to upgrade to a digital timer. I bought the Intermatic P1353ME thinking that it would easily handle the issue. But after reading through the instructions, I've learned that there is only one mode that supports a 2 pole configuration and that doesn't support a cleaner pump.

One option is to rewire to support single pole 115V. It seems both pumps have that as an option but I will need to at least rewire the connection to the main pump. That would even leave me a third circuit designate as AUX that I could put my lights on. This sounds like a great idea, however someone cautioned me against this saying that although it would work, pumps are more efficient at 230V and it is less "difficult" for the motor to start. They recommended that I return this digital timer switch and find an appropriate timer that will support two 2-pole 230V circuits. Well, that is easier said than done! I'm having a tough time finding that level of detail on most products. Is there any validity to the concern about running the pumps at 115V? If so, anyone recommend a digital timer that supports two 2pole 230V pumps?

Thanks!

Skip

 

[pwrstrk]

Welcome to TFP skip !!
I cant help ya out with this question, but somebody should be along to give you some advice.

 

[JasonLion]

The P1353ME is designed to work in this situation. It only switches one leg of a 230 volt circuit, with the other leg always connected. This is a slight safety risk in theory, but if you are using a GFCI breaker and all wiring is in conduit, both always recommended in any case, you get better safety than you would with a non-CGFI breaker and both legs switched.

To switch the pumps to 115 volts at this point you would probably need to replace the breaker and all of the wiring from the breaker to the pump. At the lower voltage you need to draw more amps, which requires heavier wire. If you upgrade the wiring, or just happen to have really heavy gauge wire already in place (unlikely), it will be fine at 115 volts.

You are able to setup the P1353ME to switch both legs of one pump and only one leg of the other pump. That setup used mode 4, with the main pump switching both legs and the booster pump either setup for 115 volts or only switching one leg.

 

[SkipFed]

Thank you for the info. That makes sense. However, I feel this is just at my limits of my understanding and ability. I'll go buy the breaker and then schedule a electrician to install. I'm just glad I don't have to return the P1353ME. I looked pretty hard and couldn't find a better suited switch. So it looks like I can plan to put it into Mode 3, where Circuit 1 controls the main pump and Circuit 3 controls the booster. I'll still have Circuit 2 available for the pool lights or whatever else.