Generator question

Good afternoon all.  We have always used our pod connected to shore power and never w/ a generator.  I always use a Surge Guard model 44260.  My brother plans on using my pod w/ a generator.  When he plugged the Surge Guard into his generator it indicated an open ground.  

Here is post from SH - found it using Advanced Search - better explanation about cause than mine:

Yes, it is simple to make. Go to your local hardware store and purchase a male plug with ground, preferably weather resistant. Take a short piece of wire (10 gauge is best followed by 12 gauge). Fasten one end to the neutral (silver colored) connector, screw or insert depending on your plug. Fasten the other end to the ground (green) connector. Do not connect anything to the third (gold/brass colored) connector. Close the housing and then use a little silicone to seal where the wire would normally go through. You will then have a functional neutral bonding plug for a lot less than Progressive Industries would want to charge.

Plug it into one of the outlets on your generator. Plug your cord into the other outlet (assuming a 2000 watt generator with a dual 15A plug). If you have a 30A outlet, plugging the neutral bonding plug into the 15A outlet should also provide the bonding for the 30A outlet.

I made one. It only took a few minutes (plus time for the silicone plugging the hole to cure). I tried it and it works very well. The reason you need one with a generator is that most generators have a "floating neutral" unlike the power coming from your home's outlets or the post in an RV park. There, the bonding is done at the service panel. The circuit analyzer is expecting bonded neutral and the plug provides this.

Mike and Stephen, thanks for your help.  I will be passing on the detailed info you provided.