27 volts at coach and truck batteries

[odysseybernard]

Reinstalling my generator and thought I would check the voltage to make sure I had the hot 12 volt wire connected correctly at the generator. I'm getting around 27 volts at the hot 12 volt DC starting wire at the generator???.

So I used the voltmeter to check the voltage at the coach battery which was also 27 volts. So I then check the voltage at the truck battery, which was also 27 volts. Is this normal???? Shouldn't it be 13 to 14 volts everywhere?

Or maybe do I have a bad isolator and the coach and truck batteries are connected in series??? I have the solenoid cylindrical type isolator on the firewall.

I don't want to fry my now functioning fixed  generator with 27 volts to start it, although I'm suspecting it has always been 27 volts even before I pulled the generator out of the RV, and it never hurt it before. 

Thanks.

 

[Maineah]

You have an issue with your voltmeter it's either on the wrong scale or it came from harbor freight. If it was that high you would have burnt out bulbs, no water in the batteries and other serious problems. Could it be series wired? Well maybe but it would be hard to do and if you check each battery at it's source it still would read 12 volts you would have to bridge both at the same time to read 24. So if each were indeed 27 volts the combined voltage would be 54 volts.

[odysseybernard]

Thanks for the reply. You're right, I had the voltmeter on a/c instead of d/c.  It now reads correctly. Can't blame that on being a senior!

 

[Maineah]

Maybe you can't but I can I are one! Good I'm glad your mystery is solved.