2 Meters, 2 Buildings, 1 Property

[TOOL_5150]

Im not used to this type of setup, so let me explain what I got. 1 property has 2 houses on the lot, OH drop to 2 seperate meters, feed from 1 of the meters goes OH to the second house [about 20 feet]

Each meter goes to a panel, that have 100A mains in them, though the 2nd houses meter has the main @ the meter - not @ the house.

I am replacing both meters, and both loadcenters, I was thinking on getting a 2 meter pack, with 2 100A breakers in them. The first house where the service enters has a plastic water main, the second has a metal main. DO I put a ground rod @ each house, and then to the water bond? What about the house with the plastic watermain? Just to verify also - if the main for the second house is @ the enterance [first house] I need 4 wires to the second house, correct? I am used to single family dewllings, so this one kind of threw me for a loop.

~Matt

 

[TOOL_5150]

Here are some pictures:

~Matt

 

[ultramegabob]

this seems like an odd set up, why not just put a meter on each house?

 

[e57]

Everyone, CA is still '05, and I think there is a change in the '08? So choose answers for the appropriate code cycle.

Not knowing more than what you have written there, and planning to put a single enclosure in the same place - then you should look at 250.32. A lot here depends on parralel metalic paths between the two buildings. i.e. Water pipes, even phone lines....

Additionally you are going to want a disconnect at the second building - especially if not accessible by residents of the 2nd building to the main at the first house by means of locked gate etc.

As for the metal water pipe it may qualify as an electrode depending on length, but would need to be bonded anyway, see 250.104A1~3. If this water pipe is IN both buildings and long enough it may serve as an electrode for both, but would consitute a parralel metalic path. (I can sense someone thinking that in one building the water would be 'exiting' the building - the pipe itself it still 'entering' for grounding purposes IMO. )

Be prepared to treat each building seperately when it comes to ground rods as either way you'll need rods at both...

 

[e57]

this seems like an odd set up, why not just put a meter on each house?

PGE may only have access to, or want one location per property. There are a number of buildings here that have cottages built in back of properties that are not accessible to PGE, and have the metering for both/all in the primary building at the front of the lot. While OH between building is rare on them it does happen... Most of them are a UG or even surface feeder from the front building.

 

[TOOL_5150]

Everyone, CA is still '05, and I think there is a change in the '08? So choose answers for the appropriate code cycle.

Not knowing more than what you have written there, and planning to put a single enclosure in the same place - then you should look at 250.32. A lot here depends on parralel metalic paths between the two buildings. i.e. Water pipes, even phone lines....

Additionally you are going to want a disconnect at the second building - especially if not accessible by residents of the 2nd building to the main at the first house by means of locked gate etc.

As for the metal water pipe it may qualify as an electrode depending on length, but would need to be bonded anyway, see 250.104A1~3. If this water pipe is IN both buildings and long enough it may serve as an electrode for both, but would consitute a parralel metalic path. (I can sense someone thinking that in one building the water would be 'exiting' the building - the pipe itself it still 'entering' for grounding purposes IMO. )

Be prepared to treat each building seperately when it comes to ground rods as either way you'll need rods at both...

Both buildings are owned my 1 person, whom is living in the back house. I intended on getting a MB panel for the 2nd house. I will bond the water @ each residence - Not sure if there are 2 water meters, there are 2 gas, electric and looks to be seperate phone lines - so its likely there is 2 water meters.

I am now leaning towards 2 seperate meter sockets and mains, as a 2 gang meter pack is much more expensive. Ill have to call CED tomorrow to see if they can give me a good price.

~Matt

 

[TOOL_5150]

PGE may only have access to, or want one location per property. There are a number of buildings here that have cottages built in back of properties that are not accessible to PGE, and have the metering for both/all in the primary building at the front of the lot. While OH between building is rare on them it does happen... Most of them are a UG or even surface feeder from the front building.

This is exactly the case. If i havent mentioned it, I will be changing to UG for the feed to the 2nd house in the back. Which, I believe will need 4 wires, as the main will be @ the 1st house.

~Matt

 

[e57]

Both buildings are owned my 1 person, whom is living in the back house. I intended on getting a MB panel for the 2nd house. I will bond the water @ each residence - Not sure if there are 2 water meters, there are 2 gas, electric and looks to be seperate phone lines - so its likely there is 2 water meters.
~Matt

In nearly 20 year - I have never seen two water services for a single lot - with the exception of two seperate pressures (one for fire and low for regular water) - both were always from the same HP meter. Gas 'should be seperate like electrical... and the rest will be either together or seperate, hit or miss. But always one water source per lot... (Unless they are 2 joined lots...)

This is exactly the case. If i havent mentioned it, I will be changing to UG for the feed to the 2nd house in the back. Which, I believe will need 4 wires, as the main will be @ the 1st house.

~Matt

As mentioned there is a '08 code change that we are not under yet, but this may help...
http://enews.penton.com/enews/electricalzone/codewatch/2008_09_18_september_18_2008/view.html

The 2005 version is explained fairly well here:
http://ecmweb.com/mag/electric_grounding_vs_bonding_5/

Anyway my point is even if you use PVC for the feeder to the other building - you may still have other metalic paths that would become current carrying, and become a second path for neutral current - depending on the arrangement of that water pipe, and/or any other paths that are bonded in the second building - something to watch for closely.

 

[e57]

Something else to watch for - since you don't mention much more... In most multi-family buildings a "Common Meter" is required for any common areas of the building or property. Since these are two seperate free standing structures it may not be necesary, but something to watch for if the share any common areas on the property like a garage, or other parts of one or the other structure.....

 

[TOOL_5150]

In nearly 20 year - I have never seen two water services for a single lot - with the exception of two seperate pressures (one for fire and low for regular water) - both were always from the same HP meter. Gas 'should be seperate like electrical... and the rest will be either together or seperate, hit or miss. But always one water source per lot... (Unless they are 2 joined lots...)

As mentioned there is a '08 code change that we are not under yet, but this may help...
http://enews.penton.com/enews/electricalzone/codewatch/2008_09_18_september_18_2008/view.html

The 2005 version is explained fairly well here:
http://ecmweb.com/mag/electric_grounding_vs_bonding_5/

Anyway my point is even if you use PVC for the feeder to the other building - you may still have other metalic paths that would become current carrying, and become a second path for neutral current - depending on the arrangement of that water pipe, and/or any other paths that are bonded in the second building - something to watch for closely.

Yeah, I didnt check out the water situation, not even really sure how or where the 2nd house gets the water from. I only saw where it entered the 2nd house. I know both of the gas meters are tied together @ house 1, but I am not sure if there is poly pipe between the 2 or if its coated steel. There are no common areas, but that will be a good thing to keep in mind for the future. the main house has a garage, the back house does not. They are both seperated by a fence.

~Matt