Latest Discussions : Electrical & Lighting

suzie96

09:32AM | 10/27/08
Member Since: 10/26/08
2 lifetime posts
Looking for suggestions related to the following problem. I have a pumphouse that is fed from a primary residence. The line from the residence to the pump house is 240V. This line feeds a subpanel in the pumphouse, which is equipped with a two pole 20 amp breaker. One pole of the breaker feeds a 120V outlet. The other breaker pole feeds a 120 V pump. The problem-I currently have a unbalanced voltage. That is, I currently measure ~230V at the outlet, and ~4-5V at the pump. Consequently, the pump will not run. I suspected an open neutral, but this does not appear to be the case (at least at the subpanel). Also, to troubleshoot, I disconnected the 120V circuit to the pump and the tested the remaining 120V outlet. I measure 120V at the outlet with no load, but plugged in a hair dryer to test. It did not work, and I subsequently measured ~4-5V at the outlet with the hair dryer plugged in, and turned on. Any thoughts or suggestions??

househelper

05:00AM | 10/29/08
Member Since: 03/31/05
265 lifetime posts
How many and what color are the wires that connect to the subpanel from the house?

Same question for the wires to the pump and receptacle?

Sounds like poor connections and/or loose neutral, but more details will help.

suzie96

06:07AM | 10/29/08
Member Since: 10/26/08
2 lifetime posts
From the residence to the pumphouse: relatively heavy gage (not sure of exact specification) 3-wire cable (1 black, 1 white, 1 bare ground). In the main panel within the residence, both the black and white are connected to their own breaker and energized to 120V. The bare ground connects to the ground bar in main panel.

On the pumphouse end-this cable connects to the subpanel. The black and white each feed a pole in the subpanel. The bare ground connects to the subpanel ground bar.

There is a 20 amp breaker in subpanel.

The wire for the receptacle is a standard 3 wire cable (1 black, 1 white, 1 bare ground). Black is the hot and connects to one pole of the 20amp subpanel breaker, which then connects to receptacle. White is neutral and connects from the receptacle to the ground bar in the subpanel. the bare ground runs from the receptacle to the same ground bar in subpanal as the neutral (is this to code??).

The circuit for the pump is very similiar, except of course the hot wire for the pump cable connects to other pole of the 20 amp breaker.

I too suspected loose connections and then open neutral, but I cleaned all connections in the subpanel, and replaced wire from subpanel to receptacle to no avail. Wire to pump was not replaced but "appeared" to be in condition. I am at a loss????

househelper

07:44AM | 10/29/08
Member Since: 03/31/05
265 lifetime posts
To begin with, the installation you have is NOT code compliant and could be dangerous. The bare GROUND wire should never be used as a current carrying conductor, yet in your setup, that is what is being done. The only code compliant options you have are to redo the feed to the pumphouse with 4 conductor cable, reconfigure to have only one 120V circuit available, or to have 240V only at the pumphouse.

All that being said, the easiest is to reconfigure what you have to provide 120V only service on one leg of the subpanel. The white wire at the main panel will have to be relocated to the neutral bar; the white wire at the subpanel will have to be relocated to the sub's neutral bar; the sub's neutral bar will have to be isolated from the enclosure; and the bare ground wires at the subpanel will have to be connected to a separate ground bar that is bonded to the enclosure.

Under this configuration, only one leg of the subpanel will be hot, and only 120V will be available. Once this is done, you can continue with troubleshooting, if indeed, your troubles continue.


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