Buying a new generator and cable compatible with existing transfer switch.

Background:
My house came with a generator transfer switch already installed (manual transfer). There is an outlet on the back of the house to plug in the generator (I am attaching a picture of the outlet). The generator I was looking at (Amazon.com: DuroStar DS4000S 4,000 Watt 7.0 HP OHV 4-Cycle Gas Powered Portable Generator: Patio, Lawn & Garden) will definitely handle the load but has only 120V output. The outlet on the house is a 3 prong and has 250V 20A printed inside. I will only be powering 120V devices with the generator.

Question:
Will this generator work with my current setup, or what should I look for in a generator that will work? What cord would I need to hook the generator up to my current setup?

 

We would need to know how it is wired to be sure. The 250v is simply its maximum rating. Since it is only three prong one of which should be a ground it is probably 120v. Note that is not an outlet. It is an inlet. Is it marked L520?

 

As ray stated where does that inlet go? A transfer switch? List that model..

Additionally that is the wrong inlet if its for 120v only. Should be an L5 @120v. That there is an L6 @ 240v.

 

I am guessing that the wrong inlet is installed on your house. A picture of your electrical panel would verify that.

While a 120 volt only generator can be used to power up the panel, the typical house panel is designed to accept 240/120 volts from the utility. Special precautions must be taken to hook up a 120V generator.

 

Looks to me like a 6-20 inlet. You'd have to get a new insert and move some wires around to use it.

 

Took a look at the panel and got some pictures of it. I believe the panel may be hooked up to feed both 120V and 220V appliances. However the 220V appliances would not be needed when the generator is running.

The inlet is wired into the transfer switch. The transfer switch is a Challenger D223NFC double throw safety switch. The inlet on the outside of the house is not labeled to indicate which type it is, although it looks similar to a few from the graph that was posted lawrosa.

Here are the additional pictures I took, thanks for all the help!

 

Take a pic of the main panel nest to it and all the breakers please....

 

You have the wrong inlet. You need a 14-30 inlet. Regardless of weather or not you plan to use any 240V appliances, it would still be eaiser to feed it with a 120/240 generator. Do you have any multi wire branch circuits in your panel? If you do, you can't use a 120V only generator on those circuits.

 

This whole set up is illegal due to the fact that the transfer switch was just cut in between the meter and service panel.

In order to use this transfer switch, an over current device would need to be installed between the meter and transfer switch,(all grounding and bonding in the disconnect) THEN 4-wire from disconnect to transfer switch, 4 wire from transfer switch to distribution panel(with grounds and neutrals separated) and a 4-wire generator inlet (L1430 or L1420)

 

I'm curious. Do you have a reference for that? None of the transfer switches I've installed were after the MOPD. All were upstream of it. All passed inspection and are still performing well.

 

I may have jumped the gun on my response. I was going on the notion of "equipment on the line side of a service".

After talking to an inspector yesterday, he said he would allow it since the main panel is directly adjacent to it.