Resi service ground ? Advice? - Electrician Talk - Professional Electrical Contractors Forum

leland · 04-07-2012, 08:24 AM

I think I will be compliant. Trying to save 60' 0f #4.

200A service- drop to meter pan then to a disco in side garage- back to back. 2- grd rods (rqud by poco) with #4 ground, to bond the neutral and can in the fused disco with a ground bar.

Then 4-3 with grd SER to The MLO panel, Isolated neutral,ground bar.

Now, my querry:
Inside is a metal water main. My thought is to come from the water main to the ground bar with a #4.
Electrically it looks ok, but not sure if the SER ground has to be a #4 also, or even if this would be compliant.

This is the first time I have had this dilemma,usually I will run the water main to bond at the service, however,this house set up would be a bear and costly to do that.

Thanx folks.

electricalwiz · 04-07-2012, 08:34 AM

what size panel are you picking up with 4/3 SER

mcclary's electrical · 04-07-2012, 08:47 AM

Quote:

Originally Posted by leland

I think I will be compliant. Trying to save 60' 0f #4.

200A service- drop to meter pan then to a disco in side garage- back to back. 2- grd rods (rqud by poco) with #4 ground, to bond the neutral and can in the fused disco with a ground bar.

Then 4-3 with grd SER to The MLO panel, Isolated neutral,ground bar.

Now, my querry:
Inside is a metal water main. My thought is to come from the water main to the ground bar with a #4.
Electrically it looks ok, but not sure if the SER ground has to be a #4 also, or even if this would be compliant.

This is the first time I have had this dilemma,usually I will run the water main to bond at the service, however,this house set up would be a bear and costly to do that.

Thanx folks.

The water pipe GEC must go to the service, not subpanel

HARRY304E · 04-07-2012, 09:22 AM

Quote:

Originally Posted by leland

I think I will be compliant. Trying to save 60' 0f #4.

200A service- drop to meter pan then to a disco in side garage- back to back. 2- grd rods (rqud by poco) with #4 ground, to bond the neutral and can in the fused disco with a ground bar.

Then 4-3 with grd SER to The MLO panel, Isolated neutral,ground bar.

Now, my querry:
Inside is a metal water main. My thought is to come from the water main to the ground bar with a #4.
Electrically it looks ok, but not sure if the SER ground has to be a #4 also, or even if this would be compliant.

This is the first time I have had this dilemma,usually I will run the water main to bond at the service, however,this house set up would be a bear and costly to do that.

Thanx folks.

Leland.

Are you just adding a sub panel?

or is this a full service change?

leland · 04-07-2012, 11:56 AM

PSNH- 200A panel. Cannot change entrance/ drop location.

set up:

Front of house- left to right.
drop-meter- on left side of a garage then the mud room- both slab,attached to a 60s erra ranch 40' ranch.
water main in the middle of the house- 25' to the panel location.
SER from disco to panel, up into garage ceiling, across and down mud rm. wall into the panel, 55' +-

so as you see (I hope), #4 will be close to 100'.

I'll try to post a drawing,but I am a lil' technically challenged.

Sparky J · 04-07-2012, 04:23 PM

I believe if I read this right you want to run the water pipe ground to the sub panel.
The disco is the main service location water pipe ground needs to be run there not sub panel.

Magnettica · 04-07-2012, 05:41 PM

Quote:

250.66 Size of Alternating-Current Grounding Electrode
Conductor. The size of the grounding electrode conductor
at the service, at each building or structure where
supplied by a feeder(s) or branch circuit(s), or at a separately
derived system of a grounded or ungrounded ac system
shall not be less than given in Table 250.66, except as
permitted in 250.66(A) through (C).

As mentioned, the #4 GEC has to be bonded at the main disconnect.

Shockdoc · 04-07-2012, 05:45 PM

It's non compliant to attach the GEC at the sub panel and use the SER EGC as the messenger. I did this once w/ a conduit run and bugged the sub panel ground from the GEC that ran in the sub feed conduit. As far as I see it can only be done if the GEC is unbroken to the watermain.

HARRY304E · 04-07-2012, 06:22 PM

Quote:

Originally Posted by leland

PSNH- 200A panel. Cannot change entrance/ drop location.

set up:

Front of house- left to right.
drop-meter- on left side of a garage then the mud room- both slab,attached to a 60s erra ranch 40' ranch.
water main in the middle of the house- 25' to the panel location.
SER from disco to panel, up into garage ceiling, across and down mud rm. wall into the panel, 55' +-

so as you see (I hope), #4 will be close to 100'.

I'll try to post a drawing,but I am a lil' technically challenged.

You only have to go from the main disconnect to the water meter it does not have to hit the MLO panel because because you are getting a equipment ground from the SER cable.

Your GEC only has to go from the ground rods to the main disconnect to the water meter in any order you want.

Remember your SER cable is a feeder.

k_buz · 04-07-2012, 06:37 PM

200A panel on #4 SER?

Magnettica · 04-07-2012, 08:40 PM

Quote:

Originally Posted by Shockdoc

It's non compliant to attach the GEC at the sub panel and use the SER EGC as the messenger. I did this once w/ a conduit run and bugged the sub panel ground from the GEC that ran in the sub feed conduit.

As far as I see it can only be done if the GEC is unbroken to the watermain.

Why?

Shockdoc · 04-07-2012, 09:15 PM

Quote:

Originally Posted by Magnettica

Why?

Watermain was next to old existing panel in old basement. New addition had separate basement. Ran a 1 1/4" PVC run outside underground between old main panel and new service and POA relocation. Why run two ground wires in the same conduit, a waste of resources.

leland · 04-07-2012, 09:37 PM

I knew (had a feeling) it was not right, but was hoping.

Since I needed 2 rods any way, thought that may fly. Knowing the water main is primary.

Just gonna be a 'job' now, with 2 grounds running with each other- only 2 distinct purposes.
most houses/upgrades i've done, no dif. this one is a tad unique.
oh well. pass it on to the consumer.

Thanx again.

Svtlightning207 · 04-15-2012, 07:11 PM

sorry to jump in, things have changed since ive done this. without a disconnect, would you go main panel-->water main--> 2 ground rods ---> main panel? (they require a "loop"here, wire must not be broken), then one from neutral bar in meter pan to 1 rod??? (which was not required back in the day, which is basically what im wondering, where does the bonding wire go from the meter pan)
thanks didn't mean to hijack.

RIVETER · 04-15-2012, 07:13 PM

Quote:

Originally Posted by leland

I think I will be compliant. Trying to save 60' 0f #4.

200A service- drop to meter pan then to a disco in side garage- back to back. 2- grd rods (rqud by poco) with #4 ground, to bond the neutral and can in the fused disco with a ground bar.

Then 4-3 with grd SER to The MLO panel, Isolated neutral,ground bar.

Now, my querry:
Inside is a metal water main. My thought is to come from the water main to the ground bar with a #4.
Electrically it looks ok, but not sure if the SER ground has to be a #4 also, or even if this would be compliant.

This is the first time I have had this dilemma,usually I will run the water main to bond at the service, however,this house set up would be a bear and costly to do that.

Thanx folks.

If you had to ask us you probably lost the job by now.

parnellelectric · 04-15-2012, 09:35 PM

why a #4 gec. why not #6

Manbearpig · 04-15-2012, 09:41 PM

Quote:

Originally Posted by parnellelectric

why a #4 gec. why not #6

200 amps.

leland · 04-15-2012, 10:08 PM

Quote:

Originally Posted by RIVETER

If you had to ask us you probably lost the job by now.

Nope, job is mine. just trying to save a buck. BOOO to me.

Dig this.

From the meter main, up the garage wall,across the garage ceiling (with SER),down the mud room wall to the panel (55' +-).

water main- 20' behind the panel- 35' running distance. now up the mud rm. wall, across the garage ceiling, down the garage wall to the meter. 2 ground rods (poco requirement) to the meter/main disco.
so,basically, ground and SER running the same path.

The pull is gonna bite. thats all, just trying to make life easier.
But.... If it was easy everyone would do it.

TOOL_5150 · 04-16-2012, 01:41 AM

Quote:

Originally Posted by leland

But.... If it was easy everyone would do it.

Everyone is a damn electrician around my area.

electrictim510 · 04-16-2012, 11:34 PM

Don't go to Sac! I would take Antioch customers all day compared to these Sac freaks!