New Pump/Old Wiring/No Ground Wire - need advice

Jul 16, 2015
3
Albuquerque, NM
A couple of related issues. My old pump is old brass Premier driven by a 1.5 Magnetek Centurion motor wired for 230v. I know it's at least 18 years old, but suspect it is the original equipment installed at the time of pool construction some 30 years ago. I bought a new Hayward Superpump (SP2605X7, just 3/4 horse since I've taken the heater and the spa off-line). New pump is set up for 230v. The problem is the pump instructions say that it must be permanently grounded to the green wire from the electrical service. Problem is, there is No such wire....just two hots (black) and nothing else. Wiring diagram on the old pump is still readable and clearly shows only the 2 hot connections to L1 and L2 and no ground. Taking the black-plate off the old motor confirms that there is no grounding screw. So I wired the new pump up per instructions and pulled a 12 awg green wire through the conduit, but don't know where to ground it. I fired up the pump for the first (and only) time and it only ran for about 2 seconds then shut off. I checked the breakers at the panel and it didn't appear that they had tripped since they had a full-range of motion when I pushed them from ON to OFF. That's where it sits right now....don't want to burn up a new pump, nor shock anyone. If the old pump was not able to be grounded, is that requirement for the new pump because of updated electrical codes? Is there a way to ground the pump motor without a wire going back to the panel? And finally, can the new pump shutting down be related to its lack of grounding, or maybe did I screw up when connecting it?
 
If you pulled an additional ground wire through the conduit for ground, there should be a screw for it on the new pump. On the panel side the ground is on a bar where you should see all other grounds connected. If you are unsure you could post a pic and someone can point out where it is.

If the pool and equipment is that old it likely also has no bonding. How to add that after the fact is beyond me but you should look into that as well and some here can help you with your options. You also quite possibly have a standard breaker for the pump instead of a GFCI it should be on.
 
Sorry I wasn't more clear -- I just pulled a few feet of ground wire from the new pump to the timer box hoping there was a way to ground it there. I have no secondary panel for the pool equipment, just the main panel for the house which contains the breakers for pool equipment and lighting. The pool lighting circuit is GFCI, but you are right in assuming the pump circuit is not. I don't know if replacing the existing breakers with GFCI at the main panel entirely solves the problem. I don't need the expense of having someone run new wiring all the way back to the main panel, so I am hoping for another option.

The pool is bonded and I have that wire attached to the bonding lug on the new pump.
 
You have an old pump which obviously had no ground wire. What is normal today is for a #12 green wire to go in the conduit to the pump and connect to the grounding lugs at the time clock or power source and is wired at the back of the motor on the green screw usually above the L1 and L2 connections. A lack of a ground wire would nor be the cause of a motor shutdown, unless you have a gfci
 
I figured out the pump shutting down this morning...my mistake when I replaced the jumper that I had pulled off to make room for wiring.

As far as the grounding question, I do have the ground wire attached inside the back of the motor, but on the other end, does it help to connect to the grounding screw inside the timer box if there is not a corresponding ground wire from the service panel also attached there? Since the timer box is metal and connected to the metal conduit I suppose there could be some level of grounding, but is it effective?
 
Idealy you should have a green ground wire all the way back to the service ground point. The metal conduit to the timer may or may not provide a ground connection. This can easily be checked with a volt/ohm meter. Simply probe from one hot leg to the case. If you get 120 volt reading then the ground is complete. However, Depending on where the timer is located the use of the conduit for a ground may be a code violation. If there is a conduit from the timer box back to the service, a ground wire could be pulled thru there as well to ensure a good ground path.
 
You only have the motor grounded to the pool's earth ground?

If so, that is not good. The motor should be grounded all the way back to the ground bus in your main panel. You will likely have to pull a new set of wires for your pump, which includes the ground wire. The conduit may not function as the ground.

Earth ground, and safety ground are two different things. Bonding the pump to earth ground won't help if the motor short circuits itself. Electricity will always return back to it's source, in this case the source is the main panel. Safety ground is a direct, low impedance path back to your main panel. If something shorts out, it will induce high fault current down the ground wire which will pop the breaker quickly.

Grounding can be a confusing subject.
 
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