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Mains wiring question: flush vs. surface load panel

B

Bob E.

Installing a charging station in a garage for the new car owner. The charger
is surface-mount.

The easiest install will be surface mount using liquid-tight flex on top of
the sheetrock.

Problem is that the load panel (nearby, on the same wall) is flush-mount with
knockouts (obviously) beneath the 'rock.

I'm considering running the flex on the surface and doing a "submarine"
trench / slit in the 'rock such that the flex will mate straight to the side
of the panel.

Any other ideas other than this?

(In USA.)

Thanks.
 
J

Jamie

Bob said:
Installing a charging station in a garage for the new car owner. The charger
is surface-mount.

The easiest install will be surface mount using liquid-tight flex on top of
the sheetrock.

Problem is that the load panel (nearby, on the same wall) is flush-mount with
knockouts (obviously) beneath the 'rock.

I'm considering running the flex on the surface and doing a "submarine"
trench / slit in the 'rock such that the flex will mate straight to the side
of the panel.

Any other ideas other than this?

(In USA.)

Thanks.
run wire between the studs under the sheet rock from a knock out of the
subpanel up to the joist and down the wall under the rock where the
charger will be, even though in some places it is acceptable to bore
holes no more than a specific side in the studs to pass wire
horizontally, I would wouldn't recommend it. If you do decide on
this, use rigid with feed through stud supports that can be mounted.

THe charger should have knock outs on the back panel inside for the
power entrance. Most people in this case use a rung of romix. You
simply surface mount the charger with the entrance poking through inside.

I always thought a charger was an appliance and should have a
rubber cord with cap to a surface or recessed receptacle.


Jamie
 
B

Bob E.

run wire between the studs under the sheet rock from a knock out of the
subpanel up to the joist and down the wall under the rock where the
charger will be, even though in some places it is acceptable to bore
holes no more than a specific side in the studs to pass wire
horizontally, I would wouldn't recommend it. If you do decide on
this, use rigid with feed through stud supports that can be mounted.

THe charger should have knock outs on the back panel inside for the
power entrance. Most people in this case use a rung of romix. You
simply surface mount the charger with the entrance poking through inside.

I always thought a charger was an appliance and should have a
rubber cord with cap to a surface or recessed receptacle.
Jamie

The 100A circuit needed by the charger (the actual charger is in the vehicle
-- this is really just a connector to the structure's 240 ac mains) requires
3 awg copper wire (4 awg ground). Some kind of conduit required, probably
1.25 inch. Romex not an option.

Under the 'rock is difficult: water heater & furnace are between the panel
and the charge station proposed location. Enough clearance over the 'rock but
going "sub" requires much frustration, if possible.

What's a "feed through stud support"? (Googling this gets hits relating to
threaded electrical stud, not a 2x4...)

Still think that surface mount except for the last 18 inches then going "sub"
is the best option.

These cars are 85 KWh capacities. Think "SLA charger times 10."

Thanks.
 
B

Bob E.

The only problem I see is esthetics. As long as the customer is OK
with this it will work.
You could do the "submarining" in a 6" deep J box with a cover to make
it look a little more planned. Punch a KO, low in the box for the
inside run and near the top for the surface run. Dog leg the #3 in the
box.

Thanks for the great raceway/box suggestion. One more option.
 
B

Bob E.

The only problem I see is esthetics. As long as the customer is OK
Hmm... just realized:

The load panel is sandwiched between studs. The raceway/j-box will have to be
outboard of the stud. I guess that is OK, NEC-wise, if I use a long-ish
nipple from panel knockout to j-box...
 
J

Jamie

Bob said:
The 100A circuit needed by the charger (the actual charger is in the vehicle
-- this is really just a connector to the structure's 240 ac mains) requires
3 awg copper wire (4 awg ground). Some kind of conduit required, probably
1.25 inch. Romex not an option.

Under the 'rock is difficult: water heater & furnace are between the panel
and the charge station proposed location. Enough clearance over the 'rock but
going "sub" requires much frustration, if possible.

What's a "feed through stud support"? (Googling this gets hits relating to
threaded electrical stud, not a 2x4...)

Still think that surface mount except for the last 18 inches then going "sub"
is the best option.

These cars are 85 KWh capacities. Think "SLA charger times 10."

Thanks.
Electrical Stud bushings.

Jamie
 
R

Rich.

Bob E. said:
Hmm... just realized:

The load panel is sandwiched between studs. The raceway/j-box will have to
be
outboard of the stud. I guess that is OK, NEC-wise, if I use a long-ish
nipple from panel knockout to j-box...

Do the same thing with the j-box, but go over or under the panel instead of
to the side of it.
 
B

bud--

Do the same thing with the j-box, but go over or under the panel instead
of to the side of it.

Could also use a deep j-box and half recess it in the wall. Straight
nipple to panel and surface run to the charger.
 
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