Charging batteries

[Stude55Dog]

I have a 07 Keystone 5th wheel with 5500 Onan gas generator. When I run the generator it only charges up the batteries to 11.87 volts. Is the invertor the one responsible for charging the batteries? The generator also after about an hour of running seems to start missing every once in awhile and I am wondering if when battery voltage gets low does this effect the running of the generator. Thanks

[wa8yxm]

One comment on the PDI 9180 (I have one) it came both WIth and Without a 20 amp power cord and plug. Mine is "WITH" and it failed the weekend before halloween last (over 12 years old) the new one (I got on Halloween AM) works great

Mine has the Wizard plugged in

I got the replacement (Factory Refurb) ... At the Factory (OK So I know where it is).

[Sam_Spade]

Almot wrote:
A little dirty secret of generator charging - ....

Ridiculous assertion.

The converter/charger doesn't know or care where it's input voltage comes from.......and the overall charging performance should be roughly the same regardless of the input source.

NOW.....if the generator is also running two air conditioners and the voltage is down....say around 105 volts....then the battery charging might be a bit slower but not much.

[wa8yxm]

First I'd upgarade those two parallel MARINE batts to a pair of GC-2's in series.

Now.. You ask if the INVERTER is responsible for charging YES. if it's an "Inverter/Charger" NO, if it's just an inverter like the one I just ordered.

IF you have a CONVERTER than that is its job.

And yes, low voltage can affect the operation of the generator

NOW; on the Generator there should be TWO circuit breakers, these are 2 position type (OFF/tripped and ON) make sure BOTH are ON because that might just be the tribble.

[BFL13]

You want to know first if the converter works. You need 120v input for sure, then see if there is any DC output.

The 9180 will have a plug-in for its 120 to a receptacle nearby. (that should be a 20a receptacle for the 20a plug on the 9180 or a 20/15)

Since there might be a problem getting generator or shore power to that receptacle, you could unplug the 9180 and plug it into a known good 120 receptacle (20/15 ok) via extension cord, with the battery bank disconnected. If there is 120v in, there should be 13.6 out.

Say that works. Now why didn't it get 120v in the rig?
A. Converter's breaker is popped (should be a 20a breaker not a 15)
B. Receptacle converter is plugged into is on a GFCI circuit that is popped
C. Generator/shore power transfer switch busted, so no 120 from Gen (but do the other 120v things work from gen just not the converter?)

Do you get 120v in the rig from shore power but not from gen?

50a rig? One of those "which leg is the converter on?" deals?

[MEXICOWANDERER]

Disconnection means there is no possible path for electricity to enter or leave the battery. Disconnection of the negative post is safest.

Of course the generator and shore power BOTH would be shut off before disconnecting the negative cable.

[Stude55Dog]

Almot, when you say measure disconnected or connected do you mean while generator running and/or on shore power. I found my converter and it is a Inteli Power 9100 P09180. Thanks

[Almot]

A little dirty secret of generator charging - it takes forever to charge them full. In 6 hours they probably won't be 100% charged yet, shore power or solar is what people use for that finishing stage.

Another thing: when you stopped charging and batteries are 12.38, let them sit overnight and measure again - then you will see the real voltage.

Also, measure voltage of converter. You don't have to look for converter, measure voltage on the charging cables on the battery - with battery connected and disconnected.

[Stude55Dog]

I charged 2 hours to see what the increase in voltage would be. Your right about 6 more hours of charge. Thanks

[2oldman]

Stude55Dog wrote:
I then put batteries on battery charger for two hours, 10 amp charger and they came up to 12.38 volts.

Another 6 hours and they'll probably be charged up.

[Stude55Dog]

I ran the generator for two hours and then measured with volt meter after shutting off generator. They both were 11.87 volts. I then put batteries on battery charger for two hours, 10 amp charger and they came up to 12.38 volts. Did not measure for voltage while generator was running. I have got to find the convertor as it must be buried behind the fuse panel inside. Will take batteries done for load testing while I have them charged and out of 5th wheel. Thanks

[BFL13]

Perhaps a transfer switch problem so no 120v to converter?

[2oldman]

Stude55Dog wrote:
Is the invertor the one responsible for charging the batteries? The generator also after about an hour of running seems to start missing every once in awhile and I am wondering if when battery voltage gets low does this effect the running of the generator. Thanks

If it's an inverter/charger, yes. No.

What are you using to measure the voltage? Are you measuring that after the charging is done, or during?

[ksg5000]

When hooked up to shore power or generator measure the voltage at the battery - should be 13.2 or higher. If the voltage to the batteries is OK then it's likely your batteries need replacing - have them load tested (it's free). If the voltage is less than 13.2 then test the voltage at the converter - if the converter isn't producing voltage check for the fuses on the converter and if they are OK you likely need new converter.

If voltage at converter is OK but not OK at battery check for blown fuse/breaker between converter and battery.

[Sam_Spade]

Stude55Dog wrote:
When I run the generator it only charges up the batteries to 11.87 volts.

That means that they likely aren't charging AT ALL....or at least not enough to do any good. 11.87 is about 70% discharged.

If that is the reading while the gen is running, then you have a tripped breaker or a bad converter/charger or a loose connection.

That is assuming, of course, that the 120 V output from the gen is OK.

If the reading while running is much higher and then it drops below 12 when the gen is shut off......then the batteries are SHOT or you aren't leaving it run anywhere near long enough.