By Dave Rongey Summary: A woodworking shop is set up in a storage unit and they have tapped my electrical into one of two 20A GFI circuit breakers stemming from
a subpanel on my building.
Question From Michael P-
I have a woodworking shop set up in a storage unit and have
tapped my electrical into one of two 20A GFI circuit breakers stemming from
a subpanel on my building. Upon investigation of the electrical set up, I
have looked into the subpanels of my building and the two previous(Out of 7
buildings between myself and the main breaker panel) and found that each
building has a panel that has a breaker linking it to the next in line. Two
buildings before mine feeds 2-20A circuits, one GFI for the receptacles and
one for the 70W HPS lighting circuit, and one 50 A breaker that feeds the
building just before me. The building just before me has the same 2 20A
circuits as the previous and then has a 40A breaker that feeds the panel on
my building.
My building has instead of 2 20 circuits, 4 20A circuits, two
of which are GFI protected. And all of this is being fed from a 40A breaker
in the previous subpanel? I don't have a complete electrical
understanding, but his couldnt be right could it? We are having trouble with
having enough power on our circuits in the building sometimes depending if
someone is using electricity further down in the facility. Is there any fix
by increasing the size of the breakers down the line?
Hi Michael - Great Question!
No - increasing the size of the circuit breaker is not the answer.
Increasing the capacity of the circuit by installing larger wire is, but
this must be supported all the way back to the main panel that supplies the
power for all. I sounds like the whole system needs to be configured based
upon actual loads that are being connected throughout and the upgrading the
supplying circuit.
From my experience, storage units supply only enough power for lighting to
each storage unit. If the breaker size is increased without increasing the
size of the wire then there will be a high risk of fire due to overheating
the existing wire.
Thank you for your response, that was what I had kinda figured but didn't
want to hear due to the invconvenience. They have several 70w hps ballasts
that have been burned out and not replaced for a long time now, so I am sure
they WILL NOT spend any money money on an upgrade. So the 40A on the
previous panel feeding the 4-20A circuits on mine is not a problem?
Michael P
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storage unit circuit - 1179
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This is a testing tool that is a Non-contact tester that I use to easily Detect Voltage in Cables, Cords, Circuit Breakers, Lighting Fixtures, Switches, Outlets and Wires. Simply insert the end of the tester into an outlet, lamp socket, or hold the end of the tester against the wire you wish to test. Very handy and easy to use.
This is great to troubleshoot a problem with outlet circuit wiring, is also used by most inspectors to test for power and check the polarity of circuit wiring.
It detects probable improper wiring conditions in standard 110-125 VAC outlets
Provides 6 probable wiring conditions that are quick and easy to read for ultimate efficiency
Lights indicate if wiring is correct and indicator light chart is included
Tests standard 3-wire outlets UL Listed Light indicates if wiring is incorrect, Very handy and easy to use.
A wire stripping tool used to safely strip electrical wires.
This handy tool has multiple uses:
The wire gauges are shown on the side of the tool so you know which slot to use for stripping insulation.
The end of the tool can be used to grip and bend wire which is handy for attaching wire onto the screw terminals of switches and outlets.
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