simple repair turning into a huge deal for these people because of non compliant 1980 install
I had a call to repair a four meter bank
which is then bolts to another four meter bank
The disconnect feeding these 8meters has a 225a rated main breaker.
Seven units and a common area.
240v single phase
There are [3] 4/0 Cu service drop conductors in a 2" periscope to the disco, which then continue to the [2] four meter banks.
This all was connected in 1980 - with someone's approval
All the meter sockets feed individual 100a CBs w #2 wire going up to the apts.
The seven units have gas heat and cooktops, but electric range.
Common laundry
1000 ft^2 apts
My standard 220 demand load calcs are: 17k general, 0heat, 17k appliance, 0 dryer, 40k range
Totalling 74.5kVA and 310A at 240v
Here's the problem: the existing 4/0 TW is rated
in multifamily Table 310.15(B)(16) (formerly Table 310.16)
195a
Even w THHN and calling it 75^ its 230A
The existing main disconnect is 225A
The arcing at the socket was happening at the load to the individual unit so I don’t believe it has to do with the wire being too small as there is #2 to the unit.
The whole job comes from the Repair.
HOA can’t believe the existing was non compliant in 1980 and is fighting to just have the repair done - just replace the bad 4 meter bank.
If I could get approval to just upsize the service drop and the feed to the [2] 4meter banks, the buss would need to be 400a. Existing buss is 225A with 125 sockets
And on top of it the working clearances are 29” to the glass!
The nearest place to move the meters is about 30’ away from where the drop is anchored.
Away from the drop to the back of the lot.
Lights were flickering in one unit.
The main has never tripped.
So am I correct in thinking that the repair has brought this to light and there is no way to avoid a very costly [and some would say totally unnecessary overreach by local authority] or is there something I haven’t thought of?
Ampacities haven’t changed since 1980
Working Clearances haven’t changed.
https://photos.app.goo.gl/FUKQXzAEEBSUL3Wf7
how did this ever get approved in 1980?
I had a call to repair a four meter bank
which is then bolts to another four meter bank
The disconnect feeding these 8meters has a 225a rated main breaker.
Seven units and a common area.
240v single phase
There are [3] 4/0 Cu service drop conductors in a 2" periscope to the disco, which then continue to the [2] four meter banks.
This all was connected in 1980 - with someone's approval
All the meter sockets feed individual 100a CBs w #2 wire going up to the apts.
The seven units have gas heat and cooktops, but electric range.
Common laundry
1000 ft^2 apts
My standard 220 demand load calcs are: 17k general, 0heat, 17k appliance, 0 dryer, 40k range
Totalling 74.5kVA and 310A at 240v
Here's the problem: the existing 4/0 TW is rated
in multifamily Table 310.15(B)(16) (formerly Table 310.16)
195a
Even w THHN and calling it 75^ its 230A
The existing main disconnect is 225A
The arcing at the socket was happening at the load to the individual unit so I don’t believe it has to do with the wire being too small as there is #2 to the unit.
The whole job comes from the Repair.
HOA can’t believe the existing was non compliant in 1980 and is fighting to just have the repair done - just replace the bad 4 meter bank.
If I could get approval to just upsize the service drop and the feed to the [2] 4meter banks, the buss would need to be 400a. Existing buss is 225A with 125 sockets
And on top of it the working clearances are 29” to the glass!
The nearest place to move the meters is about 30’ away from where the drop is anchored.
Away from the drop to the back of the lot.
Lights were flickering in one unit.
The main has never tripped.
So am I correct in thinking that the repair has brought this to light and there is no way to avoid a very costly [and some would say totally unnecessary overreach by local authority] or is there something I haven’t thought of?
Ampacities haven’t changed since 1980
Working Clearances haven’t changed.
https://photos.app.goo.gl/FUKQXzAEEBSUL3Wf7
how did this ever get approved in 1980?
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