generac 7500EXL generator bonded neutral question
#41
The NEC requires you to ground the neutral at only one location in a system:usually at the utility service entrance. Two grounds on a grounded system (e.g., 1-phase, 3-wire; 3-phase, 4-wire; or grounded delta) would result in parallel neutral and ground paths. Current will divide between the two paths and be a safety/coordination problem.
If you allow a second ground to exist, you'll end up looping the resulting parallel paths. Thus, neutral current could flow in a "de-energized" circuit and through ground relaying. Then, the main system breaker or the generator breaker could open via ground fault relaying without a ground fault. Because of the load balance inherent in generator designs, trouble may not immediately surface. Common problems that may not have immediate symptoms include such things as locating a generator on heavy harmonic circuits and not accounting for inrush. With an already compromised ground fault protection system, such a situation is a recipe for disaster.
If you allow a second ground to exist, you'll end up looping the resulting parallel paths. Thus, neutral current could flow in a "de-energized" circuit and through ground relaying. Then, the main system breaker or the generator breaker could open via ground fault relaying without a ground fault. Because of the load balance inherent in generator designs, trouble may not immediately surface. Common problems that may not have immediate symptoms include such things as locating a generator on heavy harmonic circuits and not accounting for inrush. With an already compromised ground fault protection system, such a situation is a recipe for disaster.
#47
Also did you do the continuity test with generator off? Try it with gen running .. Also tank voltage readings with meter from various points.. hot to neutral, hot to ground, etc..
#48
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information as asked:
machine OFF continuity test:
ground to neutral 0
ground to hot 0
hot to neutral 2.4
machine on continuity test:
ground to neutral: flashed a number then went to 0
ground to hot -1
hot to neutral: jumping all over readings?
volt test running:
hot to neutral 95
hot to ground 3
neutral to ground 125
machine OFF continuity test:
ground to neutral 0
ground to hot 0
hot to neutral 2.4
machine on continuity test:
ground to neutral: flashed a number then went to 0
ground to hot -1
hot to neutral: jumping all over readings?
volt test running:
hot to neutral 95
hot to ground 3
neutral to ground 125
#51
Its been a while but I see about 5volts on mine when its not plugged into anything. Once I plug into the house the 5 volts goes away...
And hot to nuetral I assume you should read 120volts..
And hot to nuetral I assume you should read 120volts..
#53
You might want to look for an electrician that has experience with wiring transfer switches and panels.
If you are using an analog multimeter no but if you are using a digital multimeter yes because they can be pron to false reading from capacitive are induced voltages. http://support.fluke.com/find-sales/...105317_A_w.pdf
I should not be seeing voltage from neutral to ground correct?
#55
Also be aware if you used a plug in tester under certain conditions they may give a false report. A final test always needs to be done with an analog multimeter or a digital meter with special circuits for reading AC.
#56
With the bonding jumper removed on the gen are you testing at the gen with the power inlet cord attached to the house? With the bonding jumper removed the gen needs to be connected to the house wiring to have a proper ground for testing.
#57
With the bonding jumper removed the gen needs to be connected to the house wiring to have a proper ground for testing.
I dont think we have reached that point yet due to conflicting test readings...
From what I know all outlets should show open ground as I remember mine does...
#58
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i have yet to find another tester to see if mine is correct or giving false readings.
maybe ill just buy another.
any suggestions or brand?
i have not gotten any further yet since my last post.
maybe ill just buy another.
any suggestions or brand?
i have not gotten any further yet since my last post.
#59
Another tester would probably give the same false reading. It is the nature of how they are constructed and work not a fault in the tester. You need to use and rely on the results of a multimeter not a plug in tester. I haven't followed the whole thread but am assuming you are talking about a simple plug in tester which is sold to test household receptacle. Not sure what the error is you keep getting. I am not a gen pro and don't want to sort through the whole thread.
#60
One thing...... NEVER check continuity with a live voltage. The OHMS function is always used on a dead circuit. That's why the meter flashed.
Are you 100% sure you did this test correct ?
There is no reason for you not to measure 120v from hot to neutral.
I'd have to go back an re-read the thread to find out what the issue. Mike may have an idea.
volt test running:
hot to neutral 95
hot to ground 3
neutral to ground 125
hot to neutral 95
hot to ground 3
neutral to ground 125
There is no reason for you not to measure 120v from hot to neutral.
I'd have to go back an re-read the thread to find out what the issue. Mike may have an idea.
#61
88rxna
Is this test with the bond lifted?
yes,i removed the purple bond wire and placed the green wire onto the receptacles neutral
Is this test with the bond lifted?
yes,i removed the purple bond wire and placed the green wire onto the receptacles neutral
#62
The green wire comes from the control board... It was on the ground but we moved it to the nuetral. It was said that the auto idle switch may not work unless it was moved...
So yes move the grn wire back and test again...
So yes move the grn wire back and test again...
#63
lawrosa
The green wire comes from the control board... It was on the ground but we moved it to the nuetral. It was said that the auto idle switch may not work unless it was moved...
So yes move the grn wire back and test again...
The green wire comes from the control board... It was on the ground but we moved it to the nuetral. It was said that the auto idle switch may not work unless it was moved...
So yes move the grn wire back and test again...
Oh... when tested with the receptacle tester I get just an open ground without a bonding plug inserted in the gen receptacle or hooked to the house. With the bonding plug inserted or hooked to the house I get correct wiring indication with the receptacle tester. Nothing weird.
#65
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Same results as last time.
If I do not move the green wire (that's attached to the circuit board) to the neutral I lose my idle control.
When I remove the bond (short purple), I get hot neutral reverse on the bottom outlet and all 3 lit for the top.
If I do not move the green wire (that's attached to the circuit board) to the neutral I lose my idle control.
When I remove the bond (short purple), I get hot neutral reverse on the bottom outlet and all 3 lit for the top.
#66
I get hot neutral reverse on the bottom outlet and all 3 lit for the top.
Seems impossible...
information as asked:
machine OFF continuity test:
ground to neutral 0
ground to hot 0
hot to neutral 2.4
ground to neutral 0
ground to hot 0
hot to neutral 2.4
Possibly ray can give better test instructions...
#67
When I remove the bond (short purple), I get hot neutral reverse on the bottom outlet and all 3 lit for the top.
#68
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Test with a multimeter
any certain test you are looking for?
volts? continuity? im a little confused since one person states never to test continuity with live voltage.
i hope i am not frustrating anyone with my ignorance. if i am i apologize.
I would like to see more meter testing as the continuity test would seem all is fine...
strange how your tester reads the open ground with yours but not mine? maybe its the brand?
#69
strange how your tester reads the open ground with yours but not mine? maybe its the brand? Yes I have no pics but my tester showed true..
I use the klein tools unit that I have had for ever...
But as ray stated it may be they are not accurate... I dont know the inter workings of them why I suggested using a different model..../make
Receptacle Tester - RT100 | Klein Tools - For Professionals since 1857
#70
strange how your tester reads the open ground with yours but not mine? maybe its the brand?
#73
Never having had a tester that beeped I have no opinion.
https://www.youtube.com/watch?v=5G622WDZaHg
#74
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ok, here are my continuity test results
generator OFF
bond connected
ground to neutral .9
ground to hot 1.1
hot to neutral 1.4
green wire from circuit board moved to neutral for idle control function AND bond removed
ground to neutral 0
ground to hot 0
hot to neutral 1.1
generator OFF
bond connected
ground to neutral .9
ground to hot 1.1
hot to neutral 1.4
green wire from circuit board moved to neutral for idle control function AND bond removed
ground to neutral 0
ground to hot 0
hot to neutral 1.1
#75
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today i shut off all breakers (main power included), attached the genny and flipped on a breaker for an outlet to test. the light tester checked out fine (connection is correct), i tested for volts and all seem fine.
does this mean im good to go?
does this mean im good to go?
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fired the genny up again as requested. the tester still gave me strange readings though, i un-hooked my power cord from the genny while it was running to see if i would get any strange readings and it lit up as correct wiring?
i tested the voltage between the hot, ground and neutral and all tested well inside of the house again.
as other have stated, im not sure i trust that tester as being correct but doing the continuity test, that showed me the ground is no longer bonded to the neutral in the genny while un-hooked from the house.