# 320A rated meter base



## RePhase277

320 amps continuous, 400 amps non-continuous. Yes, 400 amp residential services I've done generally used 320 amp sockets.


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## A Little Short

InPhase277 said:


> 320 amps continuous, 400 amps non-continuous. Yes, 400 amp residential services I've done generally used 320 amp sockets.


True, but OP is in Canada.
Probably the same but just thought you might have missed the location.


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## RePhase277

A Little Short said:


> True, but OP is in Canada.
> Probably the same but just thought you might have missed the location.


They don't have electricity in Canada! 

I just state what I know... it's up to him to verify if it's right where he is:laughing:


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## WEGI

I have installed a couple of these, both in large residential installations and small commercial. It saves both on the CT set up and electrical engineering stamp that our local utility company requires here for 400 amps and above.
Square D do a nifty 320amp all in one that will allow 2 x 200 amp breakers to sub feed 2 x 200 panels. It also gives yo an additional 8 spaces at the meter location to feed hot tubs, lawn irrigation landscape lighting etc.This really helps on cost for some of the larger residential units we wire. 
Here they also only allow a max 320 amp continuous fed from their overhead pole transformer. If you want to go to 400 amps Via a CT they now require a transformer on a pad and then the consumer is required either to run an underground or set their own pole to run an aerial set up.


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## A Little Short

InPhase277 said:


> They don't have electricity in Canada!
> 
> 
> 
> I just state what I know... it's up to him to verify if it's right where he is:laughing:


*No, they have Hydro!*:laughing:

I wasn't sure they use a 320A meter socket for 400A, so that's why I pointed out where he was.


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## Inspectorclouseau

Why is a meterbase rated 320A permitted to carry a 320A continuous load? shouldn't it be rated 320A x 125% = 400A for the conductor, equipment and main breaker size? I could see the 320A meterbase permitted to carry a 400A non-continuous load, the rationale being the load factor of a 400A non-continuous load doesn't cause over-heating of the conductors or equipment.


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## Dennis Alwon

Are you asking why the manufacturer uses 320 amp instead of 400 amp? I have no idea and it has caused lots of issues but it is rated 320 continuous and 400 non continuous. You don't see this type of meter base in a commercial setting because the loads there are rated continuous in many cases. In a residence we really don't consider most loads to be continuous


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## chicken steve

Any equipment should be measured against a demand load calc. 

So if the residence comes in under 320, one can use it 

the NEC has examples , i'm sure the CEC follows suit....you'll please pardon my bad copy/paste here....>>>




> *Example Dl(a) One-Family Dwelling *
> _The dwelling has a floor area or 1500 sq ft., exclusive of an unfinished cellar not adaptable for future use, unfinished attic, and open porches.
> 
> _ Appliances are a 12-kW range and a 5.S-kW 240-V dryer. Assume range and dryer kW ratings equivalent to kVA ratings in accordance with 220.54 and 220.5S.
> 
> *Calculated Load* /see 220.40 J
> 
> *General Lighting Load* 1500 fe at 3 VA/ft = 4500 VA
> 
> *Minimum Number of Branch Circuits Required* [see 210.JJ(A)J
> 
> *General Lighting Load:* 4500 VA -:- 120 V = 38 A
> 
> _This requires three IS-A, 2-wire or two 20-A, 2-wire circuits.
> Small-Appliance Load: Two 2-wire, 20-A circuits [see 210.1 l(C)( 1)]
> Laundry Load: One 2-wire, 20-A circuit fsee 210.JJ(C)(2)]
> Bathroom Branch Circuit: One 2-wire, 20-A circuit (no additional load
> calculation is required for this circuit) fsee 210.JJ(C)(3)}
> Minimum Size Feeder Required {see 220.401 _
> 
> General Liuhtin o
> Small AppITanc;
> Laundry
> 3000 VA at 100(/n
> 9000 VA - 3000 VA = 6000 VA at 35%
> Range (see Table 220.55)
> Dryer Load (see TaMe 220.54)
> Net Calculated Load
> Total
> Net Load
> 4,500 VA
> 3,000 VA
> 1.500 VA
> 9.000 VA
> 3.000 VA
> 2.100 VA
> 5,100 VA
> 8,000 VA
> 5,500 VA
> 18,600 VA
> Net Calculated Load for 120/240-V, 3-wire, single-phase service or
> feeder
> *18,600 VA -;- 240 V = 78 A *
> Sections 230.42(B) and 230.79 require service conductors and disconnect-
> ing means rated not less than 100 amperes.


~CS~


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## Dennis Alwon

CS, the calculated load on a residence can be 400 amps and this 320 meter base would be compliant


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## chicken steve

Then i am confused Denny.....~CS~


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## Dennis Alwon

Loads on a residence are not considered continuous and the load is so diverse that iof the calculated load is 400 amps then this base is compliant. Remember this meter base is rated 400 amps noncontinuous and 320 continuous. 400 * .80= 320.


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## 3DDesign

I buy THIS ONE  at a local supply house for $216.
I has duel lugs on the load side to feed two 200 amp main breaker panels.


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## Semi-Ret Electrician

Alabama Power gives us these meter sockets


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## Mshea

320 amp meter bases do not require additional CT or PT. They work exactly like 100 and 200 amp meter bases except that pulling a meter with a full 320 amp load would probably pull a pretty good spark so they add a shunting switch that allow the meter to be bypassed and safe for the meter tech to change or replace.

Now in Canada a load calculation done under 8-200 and gave a full load of 320 calculated amps, and not a non continuous load of 400 amps or a continuous load of 320 amps. They are only made for 240 volts single phase services and currently are not supported by BC Hydro so we can't install them yet in BC.

So no you cannot use these where the continuous load is 320 amps on a service for non dwelling units. IE the main switch would have a 400 amp breaker loaded to 80% the main OC device used with these new meters should actually be 320 amp mains. 
I expect that once Hydro has a meter they like that main breakers will be 300 amps until such time as they make a 320 amp one.


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## stewee

I have a question? When using a 320 MB for both a single family dwelling and a shop can the conductor size reduction (83%) per 310.15 (B) (7) (1) and (2) be applied to the shop panel feeder ?


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## inetdog

stewee said:


> I have a question? When using a 320 MB for both a single family dwelling and a shop can the conductor size reduction (83%) per 310.15 (B) (7) (1) and (2) be applied to the shop panel feeder ?


No.
Strong argument it cannot be used for the service conductors either.


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## stewee

Thanks, Just curious. I was sure it was pretty well defines by "Dwelling Unit".
dave


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## Cdnwirepuller

These 320 amp meter bases are being installed in Quebec, and the USA but not in my province Ontario. Meter installers don't know what manufacture make an approved meter for this amperage. What is being used in other North America locations?


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## sbrn33

chicken steve said:


> Then i am confused Denny.....~CS~


His name is Dennis. Show some respect.


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## matt1124

In canada, they hang they meter can sideways so the bypass goes left to right

Here, POCO gives us these 320amp cans for free, for a 400 amp service.

Guys here use them for solar too, since they have double lugs, they can tie in the inverter. (They make lug taps for 200A cans, but I guess they don't know that)


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