Circuit Breaker Finder

[yalgaar]

I have a Data Center where I cannot turn power off but I need to find out which PDU uses which 30 amps breaker.

I recent purchased a "circuit breaker finder" tool to help me find this out. But when I use this tool it points me that there are atleast 4 of my PDU's using the same breaker. But this is not possible becuase I know for the fact that these PDU's totally draw over 45AMPS. So it is not possible that all 4 of them are using the same breaker.

How do I find out which breakers are used for all these PDUs?

 

[dpc]

What product are you using? They are not all created equal.

And where are you located?

"The more the universe seems comprehensible, the more it also seems pointless." -- Steven Weinberg

 

[yalgaar]

I am located in NJ. I was using the "IDEA 61-532" to do my testing

 

[dpc]

http://www.aemc.com/products/pdf/2115.49.pdf

These seem to work.

I'm not sure about the Idea unit you reference. If there are a lot of harmonics that could effect the accuracy of the circuit tracer.



"The more the universe seems comprehensible, the more it also seems pointless." -- Steven Weinberg

 

[yalgaar]

Thanks for the link. But when I took the same circuit breaker tester home it worked perfectly all right.

What does this mean? Could it be a bad wiring in my data center that leaks all around and shows maximum signal on a certain breaker instead of it's own breaker.

It won't be a good idea to buy another tool which will give me the same results since the problem is somewhere else.

Any more info on this appreciated.

 

[dpc]

Well you have to consider the complexity and current density is an order of magnitude or so greater than a typical home, with very levels of harmonic distortion and neutral triplen harmonics, not to mention the radiated RFI that could be causing interference with a low-end product.

Where else would the problem be?

Call an electric supply house and ask them what they sell the most of to working electricians.

Also, how do you know what the actual current draw is on the PDU?

"The more the universe seems comprehensible, the more it also seems pointless." -- Steven Weinberg

 

[waross]

The unit is an ideaL not an idea.
Do you get any indications on other breakers?
Are these single pole breakers, two pole breakers or three pole breakers?
Are the PDUs single phase or three phase?
What voltage are the PDUs?
After you buy a clamp on ammeter, you can find your circuits by plugging in a 100 Watt or 150 Watt lamp along with a PDU.
Have someone turn the lamp on and off and check your wires at the breakers with the ammeter.
If this test shows more than one breaker, call a GOOD electrician or a GOOD engineer and be ready for a badly needed shutdown.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[yalgaar]

Well you have to consider the complexity and current density is an order of magnitude or so greater than a typical home, with very levels of harmonic distortion and neutral triplen harmonics, not to mention the radiated RFI that could be causing interference with a low-end product.

Where else would the problem be?

Call an electric supply house and ask them what they sell the most of to working electricians.

Also, how do you know what the actual current draw is on the PDU?

I have no clue about what harmonic distortion, radiated RFI or neutral triplen harmonics mean. I will read all that up as soon as I get some chance. If I have to call an electrician I would do so; but that is exactly what I am trying to find out first. Is the power circuit and wiring bad or is it just my tester not so good?

My PDU's have a digital display of the current draw.

 

[yalgaar]

That was my bad on type. Yes the tester is indeed IDEAL not IDEA.

With the tool it indicates that several PDUs on the same breaker which is not possible since the breaker is only 20amps, if I add up all the PDU's current draw it would be more than 60amps.

Not sure what it means by single pole breakers or two pole breakers. But I can tell that there are 2 columns of breakers. Each column has around 6-7 breakers.

Not sure if the PDUs are single phase or three phase.

The PDU's are 110V

As per the tool it does show the same breaker for multiple pdu's which is not possible. The question is, 1) is it bad wiring and I need an electrician to fix it? or 2) the tool that I have is not doing such a good job?

 

[waross]

If the tool shows that a PDU is connected to more than one breaker then there may be wiring issues and/or the tool may have issues.
If the tool shows more than one PDU connected to only one breaker that is probably the case.
Your questions indicate that you do not have the background or knowledge to undertake this type of testing.
Please, for both safety and accuracy, hire someone knowledgeable.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[ANGIBEW25]

I like the pacer tracer by amprobe. I also use the scotch trak by 3m.
The quality of the tracer is important in situations such as yours.
Most tracers have an adjustment on the receiver so that you can turn the setting down as low as possible to ensure that the only signal that gives a positive indication is your ciruit.
The better models will give audible and visual indication progressively as you get closer to your circuit.
In the not so long ago past we would install a fixed resistive load of anywhere between 2-6 amps. We would connect the load via a flasher (used to but them in the hardware store, the kind that screw into a lamp socket).
Good Luck.
Then we would find the circuit pulsing the current and presto you have your circuit.
You could probably make a resistive flasher for under twenty bucks.

 

[wayne440]

I have pretty good luck, here you go.

http://www.nfss.com/fbflbu60wma1.html