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I recently purchased a Champion portable 5500W generator for use with my home's existing transfer switch. It has the familiar 30A L14-30R circular twist lock connector on it, that I use with a 40ft male->female power cord. Recently when I had my local electrician over, he plugged it in for me, we test fired it and it worked well.

But now that I'm going to be using it on my own, I'm obsessed about safety, particularly the steps you take to connect it to the house. This is what the electrician did:

  1. Plug female end of cord into power inlet box on house
  2. Start generator, and let it come up to speed
  3. Plug male end into generator
  4. Go to transfer switch - make sure all branch breakers being fed by transfer switch are off (this will prevent sudden loads when moving mains to GEN position)
  5. Flip main breakers, one at a time, to GEN position, from LINE
  6. Flip branch breakers being fed by transfer switch, one at a time, to ON position

My concern really lies with steps 1-3, as there seems to be a lot of conflicting information on the net. My generator manual clearly states NOT to start the generator with loads connected. However, there is a warning in the box for the power cord that I got to connect the cord BEFORE starting the generator! So this information seems contradictory...

There is also a YouTube video here with a guy plugging in the cord BEFORE he starts the generator: https://www.youtube.com/watch?v=3_6ZpziBF-4

I'm actually starting to think either way may be OK, as long as the transfer switch mains are in the LINE position, as that will cut power off from the inlet box, right? So there would be no chance of overloading the genny at startup.

Any help you can provide is greatly appreciated. There is so much misinformation out there it's ridiculous.

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Since you have a proper transfer switch, you can safely connect the cord to both the inlet and the generator. As long as the switches on the transfer switch are in the LINE position, there should be no load on the generator.

Once you start switching from LINE to GEN, then the generator will start picking up the loads.


NOTE:

I'm not sure how your transfer switch is wired, but there should be no requirement to turn off the circuit breakers in service panel. The switches on the transfer device should handle that. They should actually break the circuit when switching between LINE and GEN. The switches will typically have three positions (LINE, OPEN, GEN), so that the circuit is always open before switching to one of the power sources.


Think of your transfer switch as having six contacts, with a shuttle that moves between two at a time.

Transfer Switch

When it's in the LINE position, the load is being supplied by the power company.

Transfer Switch in LINE position

Since there's no load on the generator, you can plug it in and start it up.

Transfer Switch in LINE position, GEN started

As you switch to generator power, the transfer equipment will open the circuit as you switch.

Transfer Switch in OPEN position

When it finally reaches the GEN position, the generator will pick up the loads.

Transfer Switch in GEN position

So as long as the transfer switches are in the LINE or OFF position, you should be fine to start the generator with the cord connected.

  • Okay, this confirms what I thought - no loads as long as the switches are in the line position. I guess I'll start the generator with the cord connected from now on. My transfer switch has no "OFF" position - just LINE AND GEN. I think it's an older design...hopefully that's still legal? – rk15000 Jan 18 '18 at 14:37
  • @rk15000 If it doesn't have an OFF position, turning off the breakers in the main panel may be required. I'd assume that the switch has an internal "OFF" position, but without knowing more about the specific equipment I can't say for sure. – Tester101 Jan 18 '18 at 14:43

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