400a service questions

[truck]

okay my shop build continues and I'm on to electricity. I've been approved for 400A separate service to the shop. I know I probably will never need that much but I am running a tankless water heater. It wasn't going to cost any more in installation or fees for the 200 vs 400 amp once they decided I needed a separate service. Again, close to same price to run separate service as to upgrade the house to 400A and run 200 off the house as the conduit & wire would have had to be replaced. So on to my question.

I was given a 320/400 Milbank meter base. I've been told that I can run 2 200A service panels ($130 per panel) off of this vise 1 400A service panel ($1200). Is this true? If so how do I connect and with what size wire? I've already mounted the meter base and have to get the service panels installed & connected before NoVec (my POCO) will come trench & lay wire to connect to the meter base.

Truck

 

[truck]

If it helps my meter base is shown in this link on page 69 of acrobat file page is labeled ID-MB2.

http://www.novec.com/documents/Electricians%20Guide%202008.pdf

Truck

 

[Charles (in GA)]

If the power company is not providing the meter base, then yes, you can use the meter base you have, it will serve the purpose. You probably also have to provide the conduit from the trench up into the meter base, just make sure of the correct size and type (SCH80) and fittings, with a long sweep 90 at the bottom. As far as connecting the meter base to your panels and equipment, I doubt the POCo is going to install the meter or provide power to the meter base until the inspector OK's it, so you are not in a rush.

You local codes may require outside disconnects at the meter, in which case you will need to install a couple of 200 amp disconnect boxes onto the meter, and from them, run the 200 amp feeds to the panels. If you don't need outside disconnects (check with your local building inspector) and you don't want them, then you could just run the 200 amp cable to directly to the panel, provided the panels each have main disconnects in them. (personally I don't like this second option, but it is quite legal, if local code doesn't dictate otherwise.) If you are using a meter base EXACTLY like the one in the illustration, it appears to have a disconnect switch lever in the meter base. If not you will surely need two 200 amp disconnect boxes attached to the meter base.

It sounds like you need an electrician at this point if you are not familiar with cable sizes and codes.

Charles

 

[walrus]

In my area the power companies have a list of approved meter bases, make sure they'll hook to that base.

 

[Charles (in GA)]

If it helps my meter base is shown in this link on page 69 of acrobat file page is labeled ID-MB2.

http://www.novec.com/documents/Electricians%20Guide%202008.pdf

Truck

Be sure and look at pages 60 and 61 for underground conduit to meter base slip joint requirements. Confirm with POCO if this is needed and who will supply it.

Charles

 

[sberry]

You will likely need 3/0 copper or 4 alum to feed the 200's

 

[bluesman2a]

I have pretty much the EXACT same setup you are talking about. I went with 2 200 Amp panels and 200 amp cut-off's. Once you go above 200 amp cutoffs, you get out of the stuff commonly available at home depot/Lowes and it gets expensive fast.

I BELIEVE (I may be wrong here) we use 00 ga. aluminum to hook from the meter base to the cut-offs and from the cut-offs into the panels. We used 4 ga. solid coper as the grounding wire, and have 2 8 foot copper grounding rods pounded into the ground, as well as a ground loop hooked to the foundation.

Another thing I might mention: Stay AWAY from the GE and Square-D Homeline panels. When I was researching them, I found the Square-D QO series components to be a little more expensive but well worth it. Based on what I found the "pinch" type breakers/panels don't handle heavy cyclical loads (compressor, on demand water heater, etc. as well).

Here are some pics, hope they help:

 

[truck]

The POCO provided the meter base shown. I had to mount it, connect & have inspected before they go any further. I don't believe the outside disconnects are required here. So I will probably set up as Bluesman & Charles have stated.

Charles - why do you not like your second option?
Blues - thanks for the tip on Homeline series, I wouldn't have thought of that.

Truck

 

[Charles (in GA)]

The POCO provided the meter base shown. I had to mount it, connect & have inspected before they go any further. I don't believe the outside disconnects are required here. So I will probably set up as Bluesman & Charles have stated.

Charles - why do you not like your second option?
Blues - thanks for the tip on Homeline series, I wouldn't have thought of that.

Truck

Sorry for the mistatement on "switch" in the meter base. I prefer to have the power disconnected as close to the meter as possible. If you just run two 4/0 service entrance cables in to two 200 amp panels, then the cable is unprotected (no fuse/circuit breaker) in the event of a problem, and the lugs on the top of the panels are always hot.

You could put two disconnects on your panel, one on the right side, one below on the right, or do as Sberry27 did and put a wireway under the right side and then thru the wall to the inside (no outside disconnects) or put disconnects on top of the wireway and then thru the wall. Disconnects are not cheap, but good insurance.

Spend some time weighing options and locations, because once its done, its done.

Charles

 

[truck]

Here is the meter base as I've currently placed it on the building. I understand what you mean about disconnects for power, however if I were using it for safety purposes above the 200A main breaker in the service panel, I would want it on the inside for quick access.

Truck

 

[Bigrhamr]

If I understand it correctly the outside disconnect is more for fire dept safety so they can kill power before going inside.

 

[ket-tek]

My setup has a 400amp service and is connected to 2 - 200amp panels. There are no disconnects between the meterbase and the panels.

I did not do the work, and now a year later I wish I had specified to use seperate disconnects from the base to the panels. I've added a few circuits since then and I'd feel safer working in the panel if I could kill the power to the input lugs/breaker.

And also If I had some kind of serious problem I could kill one panel and still keep the other one powered up..

Although it passed code, code is the minimum, which is all a builder usually provides. If you are doing this yourself I would try and see if disconnects are in your budget, if I were doing it over I would have sprung for them.

 

[truck]

Ok, I picked up a couple of QO boxes at Lowes. They didn't have 200A disconnects, neither did HD. Here is what I got and here is where I need to put it. Sorry, have to look through the scaffold. I was hanging garage door rails.


Ket-tek, where in VA are you?


Truck

 

[walrus]

You'll find alot of electricians who think QOs are the best panel made. Good choice, I wouldn't worry about disconnects outdoors as long as your run from the meter to the panel is short

 

[Charles (in GA)]

Cannot tell exactly which panel you bought. It is a 40 circuit? or is it a 30 circuit that allows 40 by the use of those more expensive "double" breakers? I want the largest panel I can find. They are easier to work in, more room. I like a panel with a full 40 spaces for full sized breakers. I assume that since you don't have disconnects outside, you bought panels with disconnects in them. Since you are not using outside disconnects, you must put both panels adjacent to each other, since the main disconnects have to be all within reach. It would be nice to put one on one side of the building and the other panel on the other side of the building, makes for shorter runs of the circuits, but you would need outside disconnects together.

Charles

 

[bluesman2a]

Ok, I picked up a couple of QO boxes at Lowes. They didn't have 200A disconnects, neither did HD.

I'll agree with Charles, make SURE you have the 200AMP panel with the 40 SLOTS, on it. There are several. Also make sure you got the panel with the main breaker in it.

I know that HD and Lowes both USED to carry the 200 Amp disconnects (in their outdoor-rated boxes). They were around $130 each, as I remember they were not right with the panels, it was tucked away elsewhere on the aisle that wasn't intuitive, but they had them in stock, just a slightly smaller box with what looks like a big 200 Amp breaker in it.

 

[Charles (in GA)]

In my case, I was only installing one panel, so I wanted the largest one possible. The price difference between a 30 slot/40 breaker panel, and a 40 slot/40 breaker panel is minimal, especially considering it is a long term investment and the possible need for future expansion.

Personally, I do not like Square D. Politically (which has nothing to do with quality or features/form/function) Square D is a French owned company. I perfer the construction and design of a Siemens panel (which is a German owned company) The Siemens panel has neutral and ground bars that extend the full length of the bus bars in the panel. Lots of room to install the grounds and neutrals without any crowding. Square D (at least the ones I've had experience with) have short ground/neutral bars, in the case of the one in my house, it has them staggered, like stadium bleachers, causing you to jam 40 grounds onto two little short, stair stepped bars. Tedious and difficult to do. Siemens breakers are 1" wide, while Square D QO series are 3/4" wide, giving the Siemens the advantage in room to work again, moving the hot wires on the breakers a quarter inch further apart.

The heaviest and sturdiest line of panelboards I've seen are the Cutler-Hammer BR series (the old Bryant Electric line) which use breakers which are functionally interchangable with Siemens and GE (full width) (the legality of which is questionable, though Siemens claims their breakers have been UL qualified in the other brands). The C-H panelboards are made from heavier steel and have metal brackets to hook the breakers on, and sturdy bus bars. GE uses a less stout steel in the box and bracketry though the galavinize on the GE boxes is nice. Siemens uses a good quality box, and a sturdy plastic mounting bracket for the breakers.

Charles

 

[bluesman2a]

Square D (at least the ones I've had experience with) have short ground/neutral bars, in the case of the one in my house, it has them staggered, like stadium bleachers, causing you to jam 40 grounds onto two little short, stair stepped bars. Tedious and difficult to do.

I don't think the newer boxes have this issue. But Charles brings up a good point. When I did my boxes, I didn't like the neutral/ground setup so I bought an extra ground bar (also Square-D, only like $5) and bolted it into the box to make the layout a bit nicer.

 

[mmg440]

I have a mix of panels at our property. I try and keep a few spare breakers on hand for repair and additional circuits. I believe the breakers for the "Square D QO" panel are a bit pricier. the the other 1" wide style breakers I have seen.

 

[sberry]

For the same money as a disconnect you can buy a 200A panel with a main lug feed thru and be able to tap it outdoors. Disconnects are required when panels are located away from point of entry, if you had a panel in another room or across the house from where it came in, etc. Nothing wrong with disconnects but it can be just added equipment and one could plan for the "what ifs" indefinitely.
The code is a pretty good guide, it doesnt always make for the best design guide for a particular case and while it is a minimum it is not just a random collection of brainstorms. Even if we added disconnects between the meter base there would still be unprotected wire to them unless the base had a built in over current device. If they think its needed its usually in the code.

 

[sberry]

I use QO because thats where I started but if I had to do it over again it would likely be Homeline due to the popularity and the cost. Would have probably saved a grand in breakers alone but I do like the visi trip indicator on the QO.

 

[bluesman2a]

Back to a earlier question: Confirmed that Home Depot still carries 200Amp exterior disconnects (at least here in Georgia). Looks to be a regular item. Sorry didn't have my phone, or I would have gotten a stock # for you, they are $127 each.

 

[sberry]

They also carry the 200A 8 space with main lug feed thru, nice for allowing feeds from outside to other buildings, well, etc. They are not much more than a disconnect and you gain 8 spaces.

 

[Aceman]

I have pretty much the EXACT same setup you are talking about. I went with 2 200 Amp panels and 200 amp cut-off's. Once you go above 200 amp cutoffs, you get out of the stuff commonly available at home depot/Lowes and it gets expensive fast.

I BELIEVE (I may be wrong here) we use 00 ga. aluminum to hook from the meter base to the cut-offs and from the cut-offs into the panels. We used 4 ga. solid coper as the grounding wire, and have 2 8 foot copper grounding rods pounded into the ground, as well as a ground loop hooked to the foundation.

Did you install 2-200 amp breakered disconnects outside along with main breaker panels inside? That wouldn't make sense. Typically the 320 amp meterbase is back to back with the 200 amp main breaker panels. There is no need for disconnect switches outside unless your local jurisdiction requires it. If they were required, I would of then went with main lug panels.

Secondly, if you have a UFER ground(concrete encased electrode) you do not need to drive rods according to the NEC.

 

[bluesman2a]

Did you install 2-200 amp breakered disconnects outside along with main breaker panels inside? That wouldn't make sense. Typically the 320 amp meterbase is back to back with the 200 amp main breaker panels. There is no need for disconnect switches outside unless your local jurisdiction requires it. If they were required, I would of then went with main lug panels.

Secondly, if you have a UFER ground(concrete encased electrode) you do not need to drive rods according to the NEC.

I have a 400+ amp meter-base, they offered me a 320, and for the price difference I insisted on the 400+. What I was told is that for THAT size meter-base code required an exterior shut-off, hence the 2 200 amp exterior cutoffs AND the breaker on the main panel. Yes more expensive, but as another person mentioned it's nice to have a choice to shut down inside or out and/or one entire side of the shop to work on the box safely while still having lights and stuff to work BY.

On the ground, there was a large SNAFU threre, I HAD the rods in the ground, but when the inspector came out, he required a UFER be installed, so I had to crack open my new foundation weld onto the rebar, and encase it. I wasn't happy about that. Once it was all said and done, I just left the rods. I just didn't want anybody else to get hit with the same surprise.

 

[Bigrhamr]

What's the details on a UFER? Ground wire clamp welded to rebar or what?

 

[walrus]

What's the details on a UFER? Ground wire clamp welded to rebar or what?

Doesn't have to be welded and it should be in your footer, make sure you use a listed clamp on the rebar and if inspection is needed make sure you do it before pouring

 

[kvom]

I have a 400a meter base serving 2 200a panels. The meter base has 2 separate disconnects. It is manufactured by Midwest Electric.

 

[truck]

Here is what I have. They are 30/40 boxes. Which I figure will be fine as that will give me 60 slots between the 2. If ya'll think different let me know. I also don't have to go with QO. I did that based on BM2's comment.

Truck

 

[mmg440]

Still unused and returnable. I would go with the 40 full slots. If you split your circuits up and have a lot of equipment the slots get used pretty quickly. I would assume with a 400 amp service you plan to have some equipment out there! What seems like plenty now could be a issue latter and it is only a little cost now but the expense of adding another sub panel or replacing one of the main ones latter.

The QO is most likely a better product. I do like the tripped window although I have seen tripped breaker not flag the window in the past. My self I would probably go with the standard homeline or GE panel. They seem to have been proven reliable and quite a bit cheaper and when buying 20 or so at a time including dual 220 breakers it adds up mighty quickly.

Just my opinion

 

[Charles (in GA)]

Yep, those have those short little ground and neutral bars. My Siemens have the bars that run the full height of the hot bus bars.

Charles

 

[truck]

Okay, I talked to the county yesterday so I thought I would share what they said. No disconnects required as long as panels have a main circuit breaker. Told to wire using #3 copper from meter base to panels. I was also told I need a seperate grounding rod for each panel and to just #6 copper from 1 panel to each rod (6' apart) and back to second panel. He also suggested bonding the neutral to the building (using #4 copper) since it is a steel building.

Truck

 

[GrantMLS]

Back to a earlier question: Confirmed that Home Depot still carries 200Amp exterior disconnects (at least here in Georgia). Looks to be a regular item. Sorry didn't have my phone, or I would have gotten a stock # for you, they are $127 each.

Only the larger stores carry them (such as ATL).. ***** when I needed to buy one in my market

 

[truck]

#3 or 3/0 ?

#3 is only good for 100 amps

Sorry you are correct ... 3/0

Truck

 

[truck]

Finally getting to work on the electrical, but have a question for you electricians out there. See pix on each point.

1. In order to connect to a flat surface on the building and get power into the panels mounted directly behind the meter base inside the building, I had to cross the PVC. I assume this is okay but wanted to ask here.

2. Also on the inside the PVC coming into the building is 28.5 inches from the floor on the left and 24 inches from the floor on the right. PVC is currently just stuck together, I haven't permanently glued anything together.

3. Finally I had to drill a hole in the service panel for entry on the far right as the knock out was only in the center.

I assume this is okay but wanted to ask here. Before I glue it all and pull & cut the 4/0 4/0 4/0 Alum wire I have to connect it all.


Truck

 

[mrb]

I prefer to have disconnects with overcurrent protection right at the meter, and not have any unprotected conductors inside. Develop a short circuit before the overcurrent protection and it just keeps arcing and burning -like this

 

[checkthisout]

I prefer to have disconnects with overcurrent protection right at the meter, and not have any unprotected conductors inside. Develop a short circuit before the overcurrent protection and it just keeps arcing and burning -like this

If I have 200 amp service, isn't the cut-out on the pole or the fuse in in-ground transformer rated somewhere around that load range?

Guy doing my electrical said the line from the meter to the fuse panel can run a maximum of 15 feet before it requires fusing at the meter. Is this true?