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Shade
Draws to much Power

Recently when my water pump for my cistern (holding tank)comes on
it draws enough juice to turn off the computer on a separate line. It has happened in the passed but periodically and never for the length of time it has been doing it lately.
I have reduced the number of loads (other equipment) on the line to no avail.
The water pump has always draw a lot of power. Enough to dim the lights for a brief second. I replaced the switch on the water pump about a year ago so i know its fairly new.
The water pump is on a line with a single light & switch only.
The computer is on a line with 4 other receptacles.
I have an 100 amp service and the home is roughly 40 yrs old.
I have not added any new line in more then 3 years time period.
Any suggestions on what maybe causing the pump to draw more power now then in the past? :confused:

Any help would be greatly appreciated.

JLMCDANIEL
Re: Draws to much Power

First just because it's on a different line doesn't mean it's not not on the same phase, so indirectly it may be on the same line. High resistance connections (corroded perhaps) could be a problem or it could just be time for a new pump.
Jack

Shade
Re: Draws to much Power

Thanks Jack for the help, it is appreciated.

I have map out the loads on each line within the fuse box with a night light. I have determined that the pump is on a separate line by itself. Also two fuses (lines) are empty.
How does one test for the phasing issue?
I checked the pump wiring both at the pump and the fuse box and all seems to be fine with no corrosion seen. I also plugged the pump into another circuit with only one load and the problem of the pump still drawing a lot of power still occurs.
How does one know if the pump needs replacing or if there is corrosion of the wiring?

JLMCDANIEL
Re: Draws to much Power

With a volt meter. If you chose one line and check the voltage between it and each of the others. If the voltage reads 0 it is on the same phase if it reads 220 that line is on the other phase.

One thing you might want to try, if the motor is a capacitor start motor. It will probably have a can on it like the one pictured on top of this motor It may be getting weak. You should be able to get a replacement at a store like Grangers. Be sure to turn of the power and discharge the capacitor by shorting across the lead with an insulated screw driver so you don't get zapped. It may also have a centrifugal switch that switches from start to run windings. If it's the problem you should notice the pump running at low speed for and extended period of time which will cause it to draw excessive power. The centrifugal switch can be replaced but should be done by someone who knows what they are doing. It might be just as cheap to replace the motor.
Jack

JLMCDANIEL
Re: Draws to much Power

Actually before someone else jumps in and corrects me, it's not a seperate phase it's a seperat leg of a single phase .
Jack

NEC
Re: Draws to much Power
JLMCDANIEL wrote:

Actually before someone else jumps in and corrects me, it's not a seperate phase it's a seperat leg of a single phase .
Jack

Jesh, Jack..... There is A RAT in in separate...... Learn to spell. LOL

Ernie_Fergler
Re: Draws to much Power

Would not by peering into the load center you could tell you the phasing as well?

JLMCDANIEL
Re: Draws to much Power
NEC wrote:

Jesh, Jack..... There is A RAT in in separate...... Learn to spell. LOL

Ghees, you'er ruthless.:D
Jack

Re: Draws to much Power

If the pump is in a location subject to a lot of moisture the comments about corrosion are probably right on. The corrosion (&/or rust) could be in the connections, the bearings in the motor, in the motor windings, or on the magnets in the motor. You could have worn brushes in the motor such that the springs aren't holding them in as tightly. Does the pump motor require oiling? If so, have you oiled?

If the pump is in a area favored by insects maybe bugs or spiders have invaded the motor and created excess friction when it tries to run.

Moon Over My Hammy
Re: Draws to much Power

An electrician should check out your panel and wiring. Circuits without fuses shouldn't have power if they do someone may have jumped them which wouldn't be safe, like with a wire connection or a penny.

An electrician will check the main from each side or half phase to ground to read the voltage on each side or half the bus, will check connection to earthing with megger, and check continuity. If necessary will check the voltage and resistance from the meter to the panel. Will also check individual branch circuits and investigate if you have multiwire branch circuits.

about 40 years ago puts the time frame for old style first generation aluminum wiring possibly - this needs to be checked for also.

The problem could be anywhere including the circuit supplying the computer or the incoming service, or the panel arrangement.

I'm only familiar with water supply pumps that are on 120/240 circuits that are hard-wired not having plugs, and these are usually also set up with a fused disconnect. Usually by 40 years ago the house panel was circuit breakers (late 60s) not fuses. Maybe your system is older than 40 years old.

Fencepost
Re: Draws to much Power

A weak power supply in the computer could be making the problem appear worse. They do go bad over time, especially if there has been a lot of voltage fluctuation. Surge suppressors do not protect your computer from voltage drops, but some UPSs do. Replacement power supplies cost around $40-50 and are pretty much universal fit.

You might also check the tightness of the screws on all the outlets on the circuit where your computer is. A loose connection somewhere on that line could be making the problem worse. And if any of the outlets are "backstabbed" -- that is, the wire goes into a hole in the back -- you should consider redoing it with a sidewire where the wire is wrapped under a screw. (Make sure only one wire per screw.)

Have the power company check for corrosion on and the tightness of the lugs in the meter base, any intermediate connections, and where the lines come into the electrical panel. You shouldn't do this yourself, since you won't have the ability to shut off the power to these lugs -- it's all upstream of your main breaker or fuses.

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