200 & 200 dosen't = 400

[Hendrix]

I just saw a residential service wired in 1969 (and inspected). From the metersocket came two pieces of 4/0 SEU to two 400 amp fuses inside a 400 amp switch. From there two pieces of 4/0 SEU continue to two sub panels with 200 amp main breakers.
Could this have been legal in 1969 I asked a couple of "old timers" about this inspector (he left a inspection certificate with his name on it stapled to the panelboard) they remember his not allowing 14/2 romex or 1/2 inch emt also.

 

[iwire]

It could be legal today depending on how the panels are from the switch

 

[Hendrix]

It could be legal today depending on how the panels are from the switch

How the panels are from the switch? If you mean how far, they are through the garage and into the basement.....about 60'

 

[iwire]

How the panels are from the switch? If you mean how far, they are through the garage and into the basement.....about 60'

Yes I meant how far, it could have been legal under the 25' tap rule.

 

[Hendrix]

Yes I meant how far, it could have been legal under the 25' tap rule.

So you're saying it wouldn't need a grounding conductor?

 

[Hendrix]

So you're saying it wouldn't need a grounding conductor?

Also, I miss-spoke, the 200A panels are main lug, not main breaker:roll:

 

[Dennis Alwon]

Also, I miss-spoke, the 200A panels are main lug, not main breaker:roll:

A ser cable would have been required.

 

[Hendrix]

A ser cable would have been required.

And, there is nothing wrong with the SEU being fused at 400 amps ?

 

[Dennis Alwon]

And, there is nothing wrong with the SEU being fused at 400 amps ?

I thought Bob answered that with the 25' tap rule

 

[Dennis Alwon]

Also, I miss-spoke, the 200A panels are main lug, not main breaker:roll:

The 200 amp panels would need a breaker for the tap rule to be in effect.

 

[Hendrix]

I thought Bob answered that with the 25' tap rule

OK, I get it now. Thanks

 

[Hendrix]

The 200 amp panels would need a breaker for the tap rule to be in effect.

Thanks for clearing that up.

 

[Pierre C Belarge]

If they are installed as tap conductors, the conductors are required to be protected by a raceway

 

[Hendrix]

If they are installed as tap conductors, the conductors are required to be protected by a raceway

In which case the SE cable would be no good.

 

[Dennis Alwon]

If they are installed as tap conductors, the conductors are required to be protected by a raceway

I should have posted the article. I guess Mike didn't include that in the graphic.

240.32(B)(2) Taps Not over 7.5 m (25 ft) Long. Where the length of the tap conductors does not exceed 7.5 m (25 ft) and the tap conductors comply with all the following:
(1) The ampacity of the tap conductors is not less than one-third of the rating of the overcurrent device protecting the feeder conductors.
(2) The tap conductors terminate in a single circuit breaker or a single set of fuses that limit the load to the ampacity of the tap conductors. This device shall be permitted to supply any number of additional overcurrent devices on its load side.
(3) The tap conductors are protected from physical damage by being enclosed in an approved raceway or by other approved means.

 

[Jim W in Tampa]

Could be that it had 200 amp fuses at inspection and later changed to 400.
Depending on load chances are high that it never got higher than 200 so no problem. My suggestion is replace fuses and call it a day and put rejection clips in it

 

[Hendrix]

Could be that it had 200 amp fuses at inspection and later changed to 400.
Depending on load chances are high that it never got higher than 200 so no problem. My suggestion is replace fuses and call it a day and put rejection clips in it

One of the panels is filled with electric heat.
Problem is, the electrician is adding new circuits so........I'm asking to bring the whole thing up to code. What would you do?

 

[iwire]

So you're saying it wouldn't need a grounding conductor?

I had focused on the OCP, I missed the lack of SER.

I was wrong.

A ser cable would have been required.

Yeah.

The 200 amp panels would need a breaker for the tap rule to be in effect.

I agree.

If they are installed as tap conductors, the conductors are required to be protected by a raceway

Or other approved means, and that can be whatever the AHJ decides.

But all that said ..... it sounds like typical old, done wrong, worked fine for years, time to be replaced electrical work.

 

[Jim W in Tampa]

One of the panels is filled with electric heat.
Problem is, the electrician is adding new circuits so........I'm asking to bring the whole thing up to code. What would you do?

Do a new load calc. If 200 still good then easy fix replace fuses. If not then change the wire.
I think they just been very lucky for all them years. Fuses do nothing till load is above rating.

 

[jetlag]

Back then you could run as far as you wanted from the meter to the panel with no disconnect in between . Where they went wrong was installing the 400 amp disconnect . They could have ran the se to both panels if they had used 200a main breaker panels ,and now it would be grandfathered in . But back then they didnt inforce the 4 wire from a disconnect either and thats a big problem for you now. (I will add the box with the heat is not required to be 4 wire if it contains only 240 circuits). If you must have the 400 amp I believe you will have to start over all the way from a 400 meter socket designed for 2 - 200 amp disconnects.