Feed to Sub Panel, Need Some Ammunition...

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petersonra said:
that would not be compliant. you cannot have your own set of grounding electrodes for these cables. you are required to use the ones that are supposed to already be there. there should be an intersystem bonding bridge for you to connect to.
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Interesting, been doing that for years, not once has the inspector mentioned any problem with it. The local phone company also puts a ground rod at the phone line entry which is normally not on the same side of the house as the service entry and therefore no ground rod is nearby. Does the same rule apply to telco installs? I have seen the cable company do it as well, though most of the time they save the labor and money by putting the coaxial entry near the service entry and use that ground rod.

Anyway, spoke with the inspector, he approved the conduit install for the electrical install after reviewing the conduit and looking it up, it was listed and specified to be useable for direct burial and he claims he missed that the first time, and gave me the go ahead to back fill it and cleanup. He is requiring that the LB at the garage be removed and reinstalled without gluing it directly to the flexible conduit and put a threaded LB in its place and a connector on the conduit. Minor change, although it will require removing the sub panel and cutting off the conduit through the brick wall to replace it, but the electrician i just spoke with said he can get it all done in a hour.

He didn't say a word about no ground rod at the garage, and i did question him on it, he walked over looked in the sub-panel and said "its not neutral bonded and there is a ground conductor back to the main service panel" and then walked away. Soooo... Not sure what to do there now but i will mention it to the electrician who i hired as a replacement to finish up this job tomorrow. Should i suggest to the electrician to install a ground rod or just ask him his opinion on the matter? I just don't want any more surprises so i can get this done.

The inspector is scheduled to come by for one last look tomorrow to sign off on the rough in so we can get going on final work, thankfully i was able to schedule it all so the new electrician can be here when the inspector arrives and then immediately finish the work so i don't have to install receptacle and such.
 
kb0nly said:
.... Should i suggest to the electrician to install a ground rod or just ask him his opinion on the matter?...
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Drive/bond two rods spaced 6ft. or better apart. Easiest Code compliance for second building grounding electrode system (GES) when no other electrodes are present... and a GES is required when supplied by feeder.
 
Smart $ said:
Drive/bond two rods spaced 6ft. or better apart. Easiest Code compliance for second building grounding electrode system (GES) when no other electrodes are present... and a GES is required when supplied by feeder.
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Will do! Thanks for all the help and suggestions. Looking forward to getting this job done tomorrow.
 
kb0nly said:
There is a 4x4 PVC box on the outside and the inside and joined with a piece of 1/2" conduit with a threaded adapter glued on each end and a nut inside the box, roughly in the middle of the back of both boxes. The question there is why not use a LB (conduit body) on the outside but i guess it works.
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Don't be like the inspector;) LB may look nicer, but nothing prohibits the 4x4 box either. If you want to spend the $$ you could put in a 48x48x12 box and it is still NEC compliant - as long as rated for the environment anyway.

kb0nly said:
Interesting, been doing that for years, not once has the inspector mentioned any problem with it. The local phone company also puts a ground rod at the phone line entry which is normally not on the same side of the house as the service entry and therefore no ground rod is nearby. Does the same rule apply to telco installs? I have seen the cable company do it as well, though most of the time they save the labor and money by putting the coaxial entry near the service entry and use that ground rod.

Anyway, spoke with the inspector, he approved the conduit install for the electrical install after reviewing the conduit and looking it up, it was listed and specified to be useable for direct burial and he claims he missed that the first time, and gave me the go ahead to back fill it and cleanup. He is requiring that the LB at the garage be removed and reinstalled without gluing it directly to the flexible conduit and put a threaded LB in its place and a connector on the conduit. Minor change, although it will require removing the sub panel and cutting off the conduit through the brick wall to replace it, but the electrician i just spoke with said he can get it all done in a hour.
.
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Even before NEC required us to install intersystem bonding devices - it still required those other systems to be bonded to the electrical system grounding system. You could drive all the rods you want to for a telephone or TV system, but the only way to ensure there is no potential between those systems and the electrical system is to bond them together at some point - that is just plain physics no matter what codes may be.

I think most liquidtight flexible nonmetallic conduits are rated for direct burial. The issues with burying them is physical protection where they emerge from the ground. There is no rule that prohibits them from emerging and is kind of up to the AHJ to determine if the wall of the conduit is strong enough to endure any physical abuse it may be subject to. You will get different opinions from nearly everyone that is tasked with making this determination, and specifics of each installation will come into play.

The LTFNMC cemented into the conduit body - probably will pull out without too much trouble. (won't say I've never done this or seen it;), but they don't hold all that well in most cases when you do this). Cement in a short PVC nipple and female adapter and then install the flex fitting into that.
 
Thanks for all the help guys! Was good hearing the suggestions and how to handle it.

Got it all done. Thankfully the new electrician was a smart fellow and handled it superbly. You were right about the LB not being glued on well, he pulled the flex right out of it and managed to snake the wires back out and then glued in the proper adaptation to the flex and then slid it all back together.

Grounding installed, all grounding bonded together as suggested and he seemed to know what to do without me even asking, but thankfully I knew what to look for with everyone's replies which really made me confident in the new guy when he started looking over the previous guys work and started suggesting what to do with the grounding. It's all safe and sound now.

About two hours work and the problem was solved the inspector signed off and he got to the final work and had working receptacles before I could even get a wall mount hung for the TV. Just plain fantastic.

Best part is I have new guy I feel I can trust for future jobs and call in on consults when customers start asking for something special. Nice having a go to guy with a can do attitude on my side again!

Now tomorrow I can polish off this job and move on. Still haven't resolved with the previous electrician for his small contribution. But then he isn't answering the phone so I guess I wait and see what he does. If he wants to get paid the ball is in his court.

Thanks again!
 
DrSparks said:
only if you're changing the overcurrent rating of the circuit. for example, you run a 10-3 to a 30am box with 2 x 20a breakers.
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Where are you getting that from?

Feeder. All circuit conductors between the service equip-
ment, the source of a separately derived system, or other
power supply source and the final branch-circuit overcurrent
device.
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If you land in a box with breakers in it it's a feeder.
 
DrSparks said:
only if you're changing the overcurrent rating of the circuit. for example, you run a 10-3 to a 30am box with 2 x 20a breakers.
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If there is any overcurrent device (excluding supplemental overcurrent protection as an integral part of utilization equipment) installed in the circuit integral with or after the building/structure disconnecting means, the supply is a feeder. Refer to the Article 100 definition of a feeder.
 
ActionDave said:
Where are you getting that from?



If you land in a box with breakers in it it's a feeder.
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Not necessarily. I've gotten into arguments with Madison inspectors on this. Often times I'll run a 12-3 MWBC from 20a 2-pole in the house to a 2 space panel with a 2-pole 20a breaker in the garage to serve as a disconnect. I called the wires between the house and the garage a branch circuit and I was correct. I could've also used molded case switches but they weren't available to me at the time ;)
 
DrSparks said:
Not necessarily. I've gotten into arguments with Madison inspectors on this. Often times I'll run a 12-3 MWBC from 20a 2-pole in the house to a 2 space panel with a 2-pole 20a breaker in the garage to serve as a disconnect. I called the wires between the house and the garage a branch circuit and I was correct. I could've also used molded case switches but they weren't available to me at the time ;)
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You can call them what you wish. That does not change the definition. Branch circuit comes after the final overcurrent.....

Branch Circuit. The circuit conductors between the final
overcurrent device protecting the circuit and the outlet(s).
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It's just the way it is.
 
ActionDave said:
You can call them what you wish. That does not change the definition. Branch circuit comes after the final overcurrent.....



It's just the way it is.
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That, just like everything in the NEC is open to interpretation. The NEC could not possibly cover every possible use case scenario. That is why everything is subject to the authority having jurisdiction. In this case the AHJ ended up agreeing with me.
 
ActionDave said:
You can call them what you wish. That does not change the definition. Branch circuit comes after the final overcurrent.....



It's just the way it is.
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Unless, of course you can justify categorizing the last as a "supplemental" OCPD rather than a branch circuit OCPD. This comes up from time to time when fused disconnects are used for a single HVAC on a dedicated circuit.
Of course interpretations vary!
 
GoldDigger said:
Unless, of course you can justify categorizing the last as a "supplemental" OCPD rather than a branch circuit OCPD. This comes up from time to time when fused disconnects are used for a single HVAC on a dedicated circuit.
Of course interpretations vary!
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You mean like 30amp breaker ahead of a 25-amp fused disconnect? oh don't get me started on that lol.
 
GoldDigger said:
Unless, of course you can justify categorizing the last as a "supplemental" OCPD rather than a branch circuit OCPD. This comes up from time to time when fused disconnects are used for a single HVAC on a dedicated circuit.
Of course interpretations vary!
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If you rationalize the definition and requirements surrounding supplementary overcurrent protection devices, you'll realize they cannot be installed anywhere in the branch circuit wiring, lest they become a branch circuit overcurrent device... which pretty much deduces to supplementary overcurrent devices must be internal to or integral with utilization equipment.

Your typical fused disconnects for HVAC units cannot be supplementary overcurrent devices because you always have branch circuit wiring after them.
 
Smart $ said:
If you rationalize the definition and requirements surrounding supplementary overcurrent protection devices, you'll realize they cannot be installed anywhere in the branch circuit wiring, lest they become a branch circuit overcurrent device... which pretty much deduces to supplementary overcurrent devices must be internal to or integral with utilization equipment.

Your typical fused disconnects for HVAC units cannot be supplementary overcurrent devices because you always have branch circuit wiring after them.
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True. UL does make very clear what supplementary OCPDs are. We're kinda missing the original point of my argument, which has almost nothing to do with the OP question lol. I was simply saying that the local inspectors in Madison, WI have no problem with me running a MWBC to a detached garage using a 2-space panel and 2-pole 20-amp breaker as a disconnect in lieu of a molded case switch and enclosure. The ampacity of the circuit remains the same and is disconnected common trip and the neutral and ground remain isolated.
 
DrSparks said:
.... I was simply saying that the local inspectors in Madison, WI have no problem with me running a MWBC to a detached garage using a 2-space panel and 2-pole 20-amp breaker as a disconnect in lieu of a molded case switch and enclosure. The ampacity of the circuit remains the same and is disconnected common trip and the neutral and ground remain isolated.
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I'm not doubting they have no problem with you doing that... but are they telling you your supply is a MWBC or a feeder, or not telling you anything at all and just approving it?
 
Smart $ said:
I'm not doubting they have no problem with you doing that... but are they telling you your supply is a MWBC or a feeder, or not telling you anything at all and just approving it?
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Neither party is attaching any terminology to the installation. It's true that by definition, the wires between the breakers is a feeder, but both the inspector and I understand the intent of the NEC and both agree that adding a breaker in the garage poses no hazard and in fact encourages safety since there is a readily accessibly disconnect means nearby so a homeowner or future electrician doesn't attempt live work because they're too lazy to walk all the way down to the basement to disconnect the garage. Also the disconnect is in site.
 
DrSparks said:
Neither party is attaching any terminology to the installation. It's true that by definition, the wires between the breakers is a feeder, but both the inspector and I understand the intent of the NEC and both agree that adding a breaker in the garage poses no hazard and in fact encourages safety since there is a readily accessibly disconnect means nearby so a homeowner or future electrician doesn't attempt live work because they're too lazy to walk all the way down to the basement to disconnect the garage. Also the disconnect is in site.
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I have no problem with it myself... but no matter the rationale, it is non-compliant. :angel:
 
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