The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Sprinklered equipment 26-008
by twh
Today at 06:28 AM
On Delay Relay with Auto Reset
by Potseal
Yesterday at 09:59 AM
Wow, that was close!
by jraef
11/28/16 07:06 PM
Earthquake in New Zeeland
by RODALCO
11/27/16 11:25 PM
Calling all Non-US members!! (Non-US only)
by Tjia1981
11/27/16 06:33 AM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 15
HotLine1 10
Trumpy 8
Texas_Ranger 8
sparkyinak 7
Who's Online
0 registered (), 192 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Page 1 of 2 1 2 >
Topic Options
Rate This Topic
#184215 - 02/04/09 03:52 PM Phantom Power Consumption
semano Offline
New Member

Registered: 06/07/04
Posts: 3
Loc: hayward, california
desperately looking for an answer to this one. if anyone has any ideas I would appreciate it.
monthly electric bill averages about $300 a month, went over to look at this to determine the power grabbing appliance and found....................nothing! home owner wants to know if power can leak to ground. he has a 50+ year old house with MANY additional panels and circuits added. (some professionally and many done by previous home owners.) when isolating the sub panels, only the 2-pole 15A seems to be the culprit. The only thing on this circuit is the original fuse panel (4 15a circuits, 2 lighting and 2 receptacles) and some lighting and receptacles in the basement. With ALL the fuses unplugged and ONLY the 2-pole breaker turned on the meter spins like a top. With ALL the fuses plugged back in there is no noticeable difference. Any suggestions?

Top
Work Gear for Electricians and the Trades

Work Gear for Electricians and the Trades
Work Gear for Electricians and the Trades
Arc Flash Clothing, Gloves, KneePads, Tool Belts, Pouches, Tool Carriers, etc. etc....

#184217 - 02/04/09 04:24 PM Re: Phantom Power Consumption [Re: semano]
sabrown Offline
Member

Registered: 12/12/02
Posts: 297
Loc: Ogden, Utah, USA
With a clamp on meter at the service what is the amperage draw per leg?

Assuming there is a main, what is the draw with the main breaker off?

I assume you did the above when isolating the subpanel anyway. What about further isolating the things to individual circuits in the subpanel? What about turning off the breakers in the sub and monitoring the current in the feeder to the subpanel?

I would suspect a high resistant ground fault drawing about 15-20 amps somewhere.

Top
#184218 - 02/04/09 04:48 PM Re: Phantom Power Consumption [Re: sabrown]
HotLine1 Offline

Member

Registered: 04/03/02
Posts: 6804
Loc: Brick, NJ USA
Semano:
IF the billing is excessive, you should contact the utility/POCO to have the meter checked by them. Here in NJ, they have to do it, per the BPU rules.

I see from your profile, you did not state any reference to the electrical trade.

Are you saying that the 'wheel' within the electric meter (utility/poco owned) is "spinning"??

The procedure I would use is a clamp amprobe, and isolate the circuits, based on the meter reading. Then determine what is on the circuit. As sabrown said, with the 'main' off....you should have no load...zero amps on the hot legs.

I also would like to say that IF you have no electrical trade experience, you should not attempt to solve this, but hire a licensed professional.
_________________________
John

Top
#184228 - 02/04/09 06:46 PM Re: Phantom Power Consumption [Re: HotLine1]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9045
Loc: Estero,Fl,usa
If you do the math you find out a few amps 24/7 add up real fast. A 6a load @ 240v can be half of your $300 bill
As for the sub;
Are you saying the feeder on and all the branch circuit fuses out the thing is still drawing current? Look for a tap.
_________________________
Greg Fretwell

Top
#184252 - 02/05/09 08:40 AM Re: Phantom Power Consumption [Re: gfretwell]
jdevlin Offline
Member

Registered: 08/07/02
Posts: 402
Loc: welland ontario canada
Look for thing like stuck attic fan, stuck sump pump, buried line to light post or out building leaking to ground, heater the owner never new he had.
You need to trace that circuit and see where all the cables go.

Top
#184256 - 02/05/09 10:40 AM Re: Phantom Power Consumption [Re: sabrown]
brianl703 Offline
Member

Registered: 05/16/05
Posts: 165
Loc: Manassas, VA
Originally Posted By: sabrown

I would suspect a high resistant ground fault drawing about 15-20 amps somewhere.


That would produce more heat than a space heater. In fact, I would expect it to cause a fire.

Top
#184258 - 02/05/09 11:33 AM Re: Phantom Power Consumption [Re: brianl703]
SteveFehr Offline
Member

Registered: 03/19/05
Posts: 1192
Loc: Chesapeake, VA
A space heater, left on 24/7, would run about $160/year in CA. Honestly, $300/month sounds part for an electric bill. I suspect there's no short to ground or wasteful compressor or anything like that, and it's just that he's using $300 worth of electricity a month.

Top
#184267 - 02/05/09 02:02 PM Re: Phantom Power Consumption [Re: jdevlin]
LarryC Offline
Member

Registered: 07/05/04
Posts: 776
Loc: Winchester, NH, US
Also check for Refrigerator or Freezer stuck in the defrost mode.

Heat tape energized, Christmas lights left on 24/7, basement lights left on 24/7, dehumidifier stuck on,etc.

Does he have a new laser printer or copier that the owner didn't realize draw lots of current.

Larry

Top
#184268 - 02/05/09 02:39 PM Re: Phantom Power Consumption [Re: SteveFehr]
brianl703 Offline
Member

Registered: 05/16/05
Posts: 165
Loc: Manassas, VA
Originally Posted By: SteveFehr
A space heater, left on 24/7, would run about $160/year in CA. Honestly, $300/month sounds part for an electric bill. I suspect there's no short to ground or wasteful compressor or anything like that, and it's just that he's using $300 worth of electricity a month.


What are the electric rates in CA??? A typical space heater uses 1.5kw. In 24 hours it has used 36kw/h. In 356 days it has used 13,140kw/h. At 10 cents per kwh that's $1314 per year.

Top
#184270 - 02/05/09 03:58 PM Re: Phantom Power Consumption [Re: brianl703]
Ann Brush Offline
Member

Registered: 12/27/05
Posts: 155
Loc: Ohia
The only way to solve this is to do some sleuthing:

1)Clamp hot and then neutral from each circuit with a high quality sensitive ammeter and see if amps drawn = amps returned. Difference = leakage to ground, no difference = powered appliance consumption or faulty appliance.

2)Clamp hot from each circuit and one by one turn on/plug in the appliances/lights on that circuit. Check amp draw and voltage vs boilerplate or wattage and compare, small differences can add up.

"he has a 50+ year old house with MANY additional panels and circuits added" Does that necessarily mean more oportunity for ground leakage or just more legitimate consumption.

"monthly electric bill averages about $300 a month" assuming $150 of that $300 bill is excessive and cost of power is $0.12/kWh at 115V then you are looking for a total power consumption of 1.736 kW or 15 Amps, should be easy to find that.

Top
Page 1 of 2 1 2 >



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals