Emergency Question From A Lowly Carpenter

jhark123

Hello all,

We are supposed to get 90mph winds tomarrow. so, I am trying to get my generator rigged to run the house. I purchased a home this year that already has a seperate generator panel with a 20 amp input (obviously designed for a 5000wat generator). The problem is that I have a 7500 wat generator with a 30amp outlet. So, is it safe to plug a 30 amp rated generator into a 20 amp generator panel?


30amp gen outlet -------------> 20amp panel.

I know the reverse would not work as the cord would not be protected, but in this case wouldn't the 20amp breaker trip if the house attempts to draw more than 20amps from the generator?

Thanks in advance

jhark123

ETA: nevermind the manufacturers tech support finally called me back and said it's a no go.

Speedy Petey

Can you let us know what site said that?

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mrmike

probably the reason they said it was a No-No is becuase the 20a L1420 male plug & wire on the generator transfer panel would not be protected by your 30 amp circuit breaker on your 7500 watt generator,where it would be on a generator up to 5000 watt with a 20a breaker. I am not sure if you could upgrade that 20 amp plug & wire on your transfer panel to a 30 amp L1430. I would like to know myself, so I hope someone has input here.
In an emergency You could temporarily put a L1420 female plug on your 30 a cord to use it as is.with your generator.. The individual breakers on the transfer panel are protecting the circuits, so you just have to keep the sum of them under 20 amp to protect the plug and wire on the panel, until you get it updated.. Hope this helps.

jhark123

It wasn't a site that said it was a no go. I left a message with their tech support dept. and a lady called me back to say that the "system" wouldn't be protected.

rbsremodeling

hook the generator directly to the panel

bump

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kbsparky

Does your 20 Amp panel have a main breaker? A 20 Amp breaker?

If so, then make your cordset with a 20 Amp NEMA L14-20 end on it, and use it!

You should be good to go.

kgphoto

I am thinking that the lady meant the electrical line system wouldn't be protected and he would be feeding live voltage while the guys would be working on the line unless there was a transfer switch involved.

jhark123

updates:

the panel does not have a main 20amp breaker (unless it is internal and I can't see it). It has a 15amp breaker for each circuit. It is a manual transfer switch so I am confident that linemen will be protected. Also, it has a watt meter to show how much power you are drawing, so I am thinking that I can rig it up and just make sure that the watts never go over 5000. Correct?

Celtic

So how exactly does it transfer itself when utility power is restored.....at 3AM?

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jhark123

it doesn't transfer itself. Each circuit is run through the transfer switch and each circuit has a manual switch: GENERATOR---OFF---LINE POWER.

Celtic

So how will the linemen be protected from your generator when they restore power at 3AM?

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Magnettica

You need a transfer switch to manually switch from utility company power to generator power.

jhark123

Manual Transfer Switch Product Information
A.
What is it?
The EmerGen Switch provides a method to safely utilize generator power through
your existing electrical wiring during a power outage.
You’ll install this switch next to your home’s load center and connect the transfer
switch’s wires to specific circuit breakers. Once you power up your generator, you will
manually transfer that generator energy through the circuits you have chosen.
B.
Why use it?
A portable generator supplies power for one or more extension cords. This same
generator, when plugged into a transfer switch, will provide power to the existing wiring
circuits, eliminating the need for extension cords.
C.
How is it safe?
A transfer switch contains the switching which isolates the utility-supplied power
from the generator-supplied power. Because of the unique design of the transfer switch,
these two power sources cannot be ON at the same time.
The transfer switch prevents “back-feeding”, a very dangerous situation where
power flows back through the circuit breaker – usually the main breaker in the load center –
and into the power supply from the utility and cause electrical equipment to fail, or worse
yet, cause hart to line-maintenance personnel.
By properly wiring the transfer switch and controlling the switches, safety is assured


It works like every other manual transfer switch I've seen

see line "C" in the link above (can't post the url w/o 15 posts)

TimelessQuality

So....what about a transfer switch? Pretty sure you need one

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-Steve

"The most beautiful thing we can experience is the mysterious. It is the source of all true art and science." ~ Albert Einstein

Celtic

That's what I'm looking for.......we don't want the linemen needing to be rescued.


You're almost there

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jhark123

I understand you all wanting to make sure the linemen don't get zapped, that would be a bad day.

What about the plan of using a 20amp plug on my 30amp Generator cord to connect to this panel? If I keep the load under 5000 watts will the 20amp plug and wiring be safe?

Magnettica

As long as the 20 amp cord body is protected by a 20 amp breaker I don't see any problems.

However, try as you must, you'll never get close to using 5000 watts without first tripping the circuit breaker.

What kind of crap do you expect use when the power goes out?

dougchips

3 space heaters will not leave enough room for a big TV and sound system 3x1500=4500, the poor guy is under powered!

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jhark123

That's the problem, the 20 amp plug (on a 30amp cord) would not be protected by a breaker. I only want to run a gas furnace and four 60watt light bulbs