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how many cables can be fed by a 42-way panel?

how many cables can be fed by a 42-way panel?

how many cables can be fed by a 42-way panel?

(OP)
There are about 40 circuits of 120V single phase loads which are fed by a common 42 way panelboards. The loads are lighting and HVAC units. If I use 40 cables separately with glands, there are not 40 knockouts on the panel and cables are crowded on the panel surface. How many cables can a panel accommodate?

I would like to use 19mm EMT and AWG 12  or AWG 10 4-1c wire on indoor lighting circuits,what type of cable shall I use? TECK 90 or AC90?

Thanks,

RE: how many cables can be fed by a 42-way panel?

My opinion is TECK90 is superior quality –is for wet location and use XLPE as insulation and not nylon and paper as AC90. As the cable is armored you don't need EMT.
TECK 90 4*10 AWG is 21 mm overall diameter.
If the panelboard is at least 840 mm [33 inches] wide and 100 mm [4 inch] depth it is possible to arrange the cables in two rows of 20 cables per row. From here the cables will rise to a cable tray [over head].
The holes in the panelboard roof one may sealed with RTV Silicon Rubber[1 inch thick is enough, I think]
See the attachment
 

RE: how many cables can be fed by a 42-way panel?

Teck90 is expensive overkill on dry, indoor circuits.
If you can consider Electrical Metallic Tubing you are most likely in a dry location and AC90 is much cheaper than TECK90.
Glands are not needed on AC90.
Again dry type connectors for the AC90 are much cheaper than glands for TECK90 and the labour to install is less. We sometimes use dry type connectors on TECK90 in dry locations when cost is an issue.
Back to your original question,
If you are using 4/10 cable with a common neutral you service 3 circuits per cable for a total of only 14 cables.
If you are using independent neutrals you still service 2 circuits per cable for a total of 21 cables.
If that is still more than you can accommodate, run EMT to gutters, possibly 4"x4"x30" or similar. Run your cables into the gutters. Check your de-rating for the conductors in the EMT.

Bill
--------------------
"Why not the best?"
Jimmy Carter

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