I hope your rosy outlook never comes back to haunt you.
Equipment Grounding Conductor
- Thread starter gk351
- Start date
- Status
- Location
- Massachusetts
Oh the drama.
I see regularly what UL passes as acceptable grounding methods and many do not hold a candle to eight four inch conduits.
The fact is the code believes that instillation to be bonded. You pointed out that yourself, now you want to be dramatic and make it sound like it is not enough. Yeah OK.:blink:
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Oh the drama.
I see regularly what UL passes as acceptable grounding methods and many do not hold a candle to eight four inch conduits.
The fact is the code believes that instillation to be bonded. You pointed out that yourself, now you want to be dramatic and make it sound like it is not enough. Yeah OK.:blink:
Adding to that: Smart$'s argument about the series stack of all of the mechanical connections along the raceway is of little relevance when taliking about the multiple parallel visible single short lengths of RGS that are shown in the picture. :angel:
- Occupation
- Licensed Electrician
Glad to know I come across as rosy. I'm not basing my opinion on unicorns and rainbows. I'm looking at EIGHT rigid conduits with threaded fittings tied to metal cabinets on each end and linked together with metal strut. How much more bonded can something be?
Maybe they should have ditched the threader used threadless rigid connectors.
- Location
- Massachusetts
It would be "more bonded" with standard tapered threads.
I would have threaded the cut end and went straight into the enclosures with sealing locknuts on the outside and bonding locknuts on the inside. :happyyes:
:rotflmao:I think they need to be tig welded to the cabinets.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Definitely overkill. Electric spot welding will do fine because it simulates what happens during a fault. :angel:I think they need to be tig welded to the cabinets.
What proof can you bring to the discussion other than sheer conjecture?
Ever see a spot weld with current set too high?
1600A gear... what would you guess the available fault current is?
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Just the logical observation that 8 parallel sets with only two highly visible joints in each does not present the same number of critical failure points as a concealed run of multiple sticks of conduit and connectors.
A quantitative rather than qualitative argument.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Enough to melt a wire EGC?
packersparky
Senior Member
- Location
- Wisconsin
- Occupation
- Inspector
This is conjecture on your part. Do you have any proof that the EGC is compromised? :happyno:
The logical argument is: I say the concealed installation does have the same number of critical failure points. Because you suggested this premise for argument, the onus is on you to prove otherwise.
Then we have the argument whether any of the hidden failure points are compromised.
If we go as far as bringing the premise into reality, I'd rather pull wire EGC's than conceal the runs of conduit. :slaphead:
mopowr steve
Senior Member
- Location
- NW Ohio
- Occupation
- Electrical contractor
[/QUOTE]iwire: I would not hesitate to use the conduit as the EGC, those conduits have less impedance than the wire EGC you would install.[/QUOTE]
Why would anyone want to think that not having the EGC is better, after all you know it's only a matter of time before those conduit connections will become compromised by rusting/loosening/separating from the cabinets and loosing that solidly grounded state.
I know code says it's ok.
Why would anyone want to think that not having the EGC is better, after all you know it's only a matter of time before those conduit connections will become compromised by rusting/loosening/separating from the cabinets and loosing that solidly grounded state.
I know code says it's ok.
Based on experience, I see some of the threads are substandard. The grounding effectiveness under which the pertinent items are listed is based on them having standard threads. That very fact alone is enough to say the installation has several listing violations. Never mind whether the joint is grounding effective or not.
- Location
- Massachusetts
There is an EGC, actually eight of them.
I disagree that those conduits are going to become compromised before the equipment itself reaches the end of its life.
Look I do I run a lot of green wire, but in this case based on the picture I would not hesitate to use the RMC as the EGC.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
The logical argument is: I say the concealed installation does have the same number of critical failure points. Because you suggested this premise for argument, the onus is on you to prove otherwise.
Then we have the argument whether any of the hidden failure points are compromised.
If we go as far as bringing the premise into reality, I'd rather pull wire EGC's than conceal the runs of conduit. :slaphead:
OK, lets try out some numbers:
Suppose that the hidden long run of conduit has 15 joints of one type or another. Any one could be a critical failure point because they are in series.
The visible run of 8 short segments has 16 possible failure points, but none of them are critical because you have 8 EGC runs in parallel. (Leaving out for he moment any argument over whether losing one EGC and therefore potentially violating the NEC parallel conductors rule. No single failure will constitute a safety hazard for normal current operation, nor for fault current operation.) That makes zero critical failure points, none of them hidden.
I was not ever trying to assert that 15 was less than zero. Quite the contrary!
I misunderstood your premise. I thought you were talking the same number of runs (paralleled) but concealed such that we could not see any joints or substandard threads. :slaphead:
Now that I see your premise was one run of conduit (concealed, though this makes no difference in the matter) vs 8 parallel (and visible?)... I have to say that's an apples-to-oranges argument and we need not go any further. :blink:
Let put an argument back on you...
If a parallel run of 8 conduits will permit any one failure point, why do we have to run 8 full-size EGC's when we run a wire-type EGC? Why can't we just run one full-size and be done with it?
Probably. We hope the OCPD will act on a ground fault. Odds are great that it usually will. I wouldn't want to be anywhere near that equipment if the OCPD fails during a bolted fault. :happysad:
- Status