New pump wiring

Apr 10, 2013
10
Put in a new Jandy 1.5Hp, 2-speed, 240-volt pump. Previous pump was a 2Hp single speed 230-volt pump. Because I'm going to do a wiring upgrade later I decided to just hook up the HIGH speed. So I connected Line 1 to terminal #1 of the pump, and Line 2 to terminal #2 of the pump. Pump terminal #3/4 is not used. Pump does not run - nothing. Checked voltage: 124v between Line 1 and Grd; 124v between Line 2 and Grd; Zero volts between Line 1 and Line 2. Seems as if there should be 240+ volts between Line 1 & 2. What could be wrong - I'm not an electrician! Anyone with electrical knowledge that could point me in the right direction - that surely would be appreciated. Thanks again!
 
120 to ground from each? and no 240 across both? Sounds to me like you have both lines coming off the same 120 breaker, or from the same bus bar.

Trace the line into the breaker box, and make sure it is on a 240 breaker. If it is on a pair of 120 breakers, hire an electrician to change it.
 
A 240 volt circuit has two hot lines and ground. It will show 120 volts between either of the hot wires and ground, and 240 volts between the two hot wires.

What you describe sounds like both of your hot wires are the same polarity, instead of opposite polarities as they should be.

Are you sure that both of the hot wires run back to the same double breaker and the panel the breaker is installed in has 240 volts (some panels are 120 only)?
 
Sounds like you are pulling power from the same side of the panel for both legs. In this instant you will not see voltage between wires, only to ground. What type of breaker did you install? Can you post a picture of the wiring in the supply box?
 
My breaker goes thru an Instamatic time clock and ran the previous 240-volt single speed pump just fine. Between pumps there was a considerable "downtime" for the pool and the breaker box was updated, adding an emergency generator and switch. I agree that there seems to be a question of both lines being same polarity, but double (240-v) breakers always clamp onto just one and the same side of the box, don't they? Never seen a 240v breaker with one switch on one side of the box and the other one on the opposite side!? How can you form two 180* polarities on the same side of the box? Now very confused, but I'm sure someone will be able to clue me in.
 
Here is a picture of the interior of a typical load center, or "breaker box".,



As you can see, there are two "busses" that the breakers attach to. Your normal 120 breaker clips onto just one of the interleaved cross pieces, and a 240 clips to two adjacent cross pieces, giving you the opposing "polarities" (not the correct term).

IF the previous owner had use two 120 breakers (highly inadvisable btw), when you had the panel updated, the electrician may have inadvertently put the two 120's on the same buss bar, not on separate.

To explain why two 120's is not equal to one 240 -- say something happens to one "leg" of the 240 line, and it shorts to ground. the breaker it is on does it's job. the other 120, not having a short, stays on. So at whatever you are powering, you still have an energized circuit. This is why toe 240, or more correct "two-pole" breakers are always tied together, either externally, on the handles, or internally. So both sides of the 240 circuit are de-energized, or "killed".
 
ekbishop1 said:
but double (240-v) breakers always clamp onto just one and the same side of the box, don't they?
In modern boxes, yes they do. However, they do not clip onto the same phase. Double pole breakers have two terminals that clip onto each of the two separate phases. There are also what are called double breakers. These have two disconnect switches and two output terminals but, only clip onto one phase of the service. The are used in select slots in boxes to allow for more room. These can sometimes be confused as two pole breakers

ekbishop1 said:
Never seen a 240v breaker with one switch on one side of the box and the other one on the opposite side!?
In the past there were some boxes that split the phases down each side of the box instead of the every-other-one configuration we see today. I have only ever seen one and it was on a demo we were doing to upgrade a service.

ekbishop1 said:
My breaker goes thru an Instamatic time clock

Does anything else go into this box? Maybe a lighting circuit? Just wondering if maybe a couple of leads got mixed up.

I would start at the breaker and start metering things to see what is going on. Follow the line out and check each connection point
 

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