Power issue - Page 2

imnprsd · 10-05-2020, 04:40 PM

This summer I experienced an odd power problem and my Onan 7500QD was also throwing a 46 fault code; and my EMS/PMS was not showing me any amps when on 30A power, but all my power was working on all wall receptacles.

After some trial and error I started to figure out how all these things worked separately and together. For example:

* Onan Code 46 implies many things. Some say this code gets tripped when your batteries are low on voltage; and other claim the fixed this problem by replacing the inverter board in the Onan for over $2,000. In my case, it turns out I cleared this code by doing 1 of 2 things:

A) While plugged into shore power, I started the generator. And when I pulled the shore power cord, the Onan quit running. Hmmm? ...I surmise that when I pulled the 50A power cord it disconnected the Neutral Bond in the ATS (Automatic Transfer Switch) and all was well again. However, I really can't be sure. What I am sure of is that my Onan #46 fault code is gone!

B) Even though my batteries measured 12.7V, they were badly sulfated and failed the load test. So I replaced the house batteries and all was well again. ...Could "funky house batteries" cause the Onan Inverter to throw a #46 fault code? Maybe... Probably?

I honestly don't know which of the above solutions cleared the Onan Fault Code #46, but I do know I needed new batteries, because my inverter started shutting down in 3 hrs of use, then that time dropped to 1 hour, and soon it was 15 minutes. So the more I used my coach on inverter power the worse my battery bank got! ...Why?

I think when you have 4-6V-GC2 batteries, and one goes bad, it effects all the others. You also cannot "equalize" the cells; and you cannot buy just one battery to put in the set, because that one battery will only last so long; and you will never be able to equalize your cells.

My house batteries were 2.5 years old, so the only real solution was to replace them.

INTELLITEC "Power Line" 620 EMS/PMS CIRCUIT BOARD

My circuit board is located in the Main Power Panel Box. And I have read in other posts these things you can do to fixt it:

* You need to rest the Power panel.

* If that does not work, you can pull the board and replace several resistors on the circuit board. (Search other thread for this process.)

Note: Your 30A service passes though your inverter transfer switch so if you don't have power to your wall outlets then this maybe your problem. However, I believe your ATS fails more often.

New you can go to Amazon and still buy these things:

https://www.amazon.com/Intellitec-00.../dp/B00ODJ5NN8

https://www.amazon.com/Intellitec-00...55SCAT213VRDD1

OTHER COMMENTS ABOUT POWER

* Circuit breakers only protect (trip) on the "Black" hot wire. They do not protect the neutral wire.

* You also need a good "Neutral" connection for electricity to flow.

* In 120V-AC systems you don't need a ground, but you should have one for safety reasons.

* Many 12V system problems are due to a bad ground.

Rickb33952 · 10-05-2020, 05:18 PM

I had no generator error codes while having 30 amp displayed on control panel.
I had a mobile rv tech test and nailed the problem to the board. I replaced the board because it was so much easier than repairing and after a week of shipping shopping and driving to get it, the replacement only took me 30 minutes. It did take me 5 Extra minutes to get up off the floor.

HowieB · 10-05-2020, 09:44 PM

Turns out it was the ATS. Removed the cover and found 2 of the shore power cord wire had burned insulation and one of the terminals was deformed from getting hot. I think I dodged a bullet. I overnighted a new ATS, trimmed back the shore power cord, and spent an hour changing out the ATS. Back in business. I have been making sure the ACs are turned off before plugging in to shore power. Thanks for your responses. Personally, I feel the ATS, despite my problem, is a better option than manually switching between generator and shore power.

imnprsd · 10-05-2020, 11:56 PM

Good news! I'm glad you all got your power issues resolved.

I forgot to mention on safety precaution I learned the hard way:

This summer I picked up my RV after 8 months in storage. And since there there was no outside power I could not hook-up a battery maintainer/charger. And since I park the RV under a pole barn my roof solar cells were not able to charge my house or engine batteries.

So when I arrived both house and engine batteries were not just a little dead... they were very dead! And that meant my Battery Boost Switch was of no use with both battery banks being dead.

I then decided to back up my tow car and try to jump-start the engine battery, but the toad alternator charge current was not strong enough to charge my engine batteries after 30 minutes of trying, because my engine batteries were behaving more like a big resistor instead of a big capacitor.

So I moved on trying to jump-start the generator... and I finally got the generator working.

Now I thought I would be successful trying to jump-start the engine battery while at the same time pressing the Battery Boost Switch with the generator running. ...DO NOT DO THIS!!!

It's okay to use the boost switch when one battery bank is strong and the other is dead, but not when both battery banks are weak. ...Why?

When you use the Battery Boost to start your engine with the generator running, and you have weak house batteries, you may find your generator will die as soon as you turn the ignition key, and that's never good, because you expose your Onan generator inverter board to all kinds of electrical spikes/shock.

Note: I even had a 1200A portable battery bank I first tried to use to jump my diesel engine batteries, but no-joy! So when you engine battery drops this low, it takes more than this to bring your dead battery back to life.

Also, I was able to get my sealed engine batteries working normal, but my 4 house batteries (6V Golf Cart) would not come back from the dead and ultimately had to buy new ones.

To get my engine battery started, I needed a diesel-semi tow truck (with a 180A alternator) to jump my ISC-350 engine for 15 minutes. Then it started and I was afraid to turn the engine off until I finished a 4 hour trip.

It cost me 2 hours of time to deal with my dead batteries, and $300 for diesel roadside assistance, which my insurance company reimbursed me for. But the main message here is that you should NOT try to start your engine, using your battery boost switch, when you generator is running. I.e., turn you generator off first and then try your battery boost switch or I think you could fry your Onan inverter board!

...And definitely store your coach with a battery maintainer if you can; or as a last resort, you should remove your (+) battery cables.

al1florida · 10-07-2020, 02:54 PM

Quote:

Originally Posted by imnprsd

Good news! I'm glad you all got your power issues resolved.

I forgot to mention on safety precaution I learned the hard way:

This summer I picked up my RV after 8 months in storage. And since there there was no outside power I could not hook-up a battery maintainer/charger. And since I park the RV under a pole barn my roof solar cells were not able to charge my house or engine batteries.

So when I arrived both house and engine batteries were not just a little dead... they were very dead! And that meant my Battery Boost Switch was of no use with both battery banks being dead.

I then decided to back up my tow car and try to jump-start the engine battery, but the toad alternator charge current was not strong enough to charge my engine batteries after 30 minutes of trying, because my engine batteries were behaving more like a big resistor instead of a big capacitor.

So I moved on trying to jump-start the generator... and I finally got the generator working.

Now I thought I would be successful trying to jump-start the engine battery while at the same time pressing the Battery Boost Switch with the generator running. ...DO NOT DO THIS!!!

It's okay to use the boost switch when one battery bank is strong and the other is dead, but not when both battery banks are weak. ...Why?

When you use the Battery Boost to start your engine with the generator running, and you have weak house batteries, you may find your generator will die as soon as you turn the ignition key, and that's never good, because you expose your Onan generator inverter board to all kinds of electrical spikes/shock.

Note: I even had a 1200A portable battery bank I first tried to use to jump my diesel engine batteries, but no-joy! So when you engine battery drops this low, it takes more than this to bring your dead battery back to life.

Also, I was able to get my sealed engine batteries working normal, but my 4 house batteries (6V Golf Cart) would not come back from the dead and ultimately had to buy new ones.

To get my engine battery started, I needed a diesel-semi tow truck (with a 180A alternator) to jump my ISC-350 engine for 15 minutes. Then it started and I was afraid to turn the engine off until I finished a 4 hour trip.

It cost me 2 hours of time to deal with my dead batteries, and $300 for diesel roadside assistance, which my insurance company reimbursed me for. But the main message here is that you should NOT try to start your engine, using your battery boost switch, when you generator is running. I.e., turn you generator off first and then try your battery boost switch or I think you could fry your Onan inverter board!

...And definitely store your coach with a battery maintainer if you can; or as a last resort, you should remove your (+) battery cables.

Could you add more detail on why you feel the generator is affected when you have weak house batteries and you try to use the boost switch to start the engine?

I ask this because the generator does not charge the house batteries. The generator supplies 120V AC to whatever charging device you have and the charger then charges the batteries.

If you have a charger that supplies say 100amp of 12V DC charge current that means the charger will be pulling about 10 amps or maybe as much as 15 amps of 120V AC from the generator. That is not much of a load on the generator.

I have to admit I don't know what happens to the Onan generator if the batteries used to start the generator drop down to a very low voltage, say maybe 5V DC when the boost switch is pressed. Maybe that affects the generator.

Quote:

And definitely store your coach with a battery maintainer if you can; or as a last resort, you should remove your (+) battery cables.

By the way, it is much safer if you remove the cables from the minus or negative terminal first, rather than the plus terminal. If your wrench happens to contact the frame ground while loosening the cable on the plus terminal it sure makes a big spark and can weld the tool to the frame causing a huge constant load on the batteries.

thunderjet · 10-18-2020, 02:54 PM

If you would like to know how to remove your auto transfer switch I may have found the quickest method. A couple of years ago I was trying to get into the dealer for service. They said they will call when they had an opening. Well the call came and I jumped in and left. As I pulled out I saw my ats with cord still attached to the garage setting on the driveway.

Didn't hurt ats or cord but had to replace bottom half of basement compartment. I know I will never make that mistake again.

Any one else admit to removing the ats while hot. lol

TJ