Isolator, Coach Batteries Issues

[gksmith]

Originally Posted by cruising7388

I assume your 6200 reference is to a PD9200 series converter/charger..

Yes, I misspoke. It is the PD9260C unit that I am considering. The 60 Amp version looks very similar to my present converter/charger, dimension wise. I will check the feed to the battery cable. Thanks for suggesting!

I appreciate the good information that I have received both from Booster and Cruising7388, as well as others, during this episode. I feel much more comfortable now. Thanks very much!

[cruising7388]

Originally Posted by gksmith

Yes, I misspoke. It is the PD9260C unit that I am considering. The 60 Amp version looks very similar to my present converter/charger, dimension wise. I will check the feed to the battery cable. Thanks for suggesting!

I appreciate the good information that I have received both from Booster and Cruising7388, as well as others, during this episode. I feel much more comfortable now. Thanks very much!

The pendant supplied with the converter uses a standard modular telephone line and connects to the supply with the same RJ 11 connector you see on your landline telephone.

When the 9260 is fired up, the pendant shows what mode the charger is in with an LED that's pretty informative:.

Boost mode - LED stays solid green

Normal mode 1 (50 -90% charge) - LED flashes once per second

Normal Mode 2 (90 - 100%) charge - LED flashes 2-3 times per second

Storage Mode (Fully charged) - LED flashes once every 6-8 seconds

There is a button on the pendant you can toggle to force the charger into any of these modes whenever you wish.

[gksmith]

Well, it is time for my next question. First of all, I have installed new wet cell deep cycle coach batteries. They tested at 12.8 volts. And I connected the alternator cable to the engine battery cable and coach batteries upon doing the installation yesterday PM. I also purchased a battery disconnect for the engine battery and installed it this AM. As a side note, I have contacted Randy at Best Converters and have ordered one of his suggested converters--a PD4565V which is the suggested replacement for the Parallax 7435. And the Blue Sea 7622 ACR is on back order, but will be sent to my residence for future installation.

Now back to the present. Thinking that since the new coach batteries tested 12.8 volts, I would not need to plug in the shore line last night. I discovered recently, though, that I could not start my Onan generator--it would not turn over. But if I started the engine, then there was enough power to turn over the generator starter. I never had to do this before! So I began testing voltages at the batteries. First, I tested the coach batteries--they were down to 12.6 volts, but the starter battery was still at 12.8. Then I started the engine. The engine battery now registered at 14.8, as expected. But the voltage at the coach batteries remained the same, at 12.6. So I plugged into shore power. I just now checked to coach batteries (about an hour later)and they are now at 13.1 volts. So obviously the converter is doing some charging of the batteries.

So, my question is basically, "Does all of this seem normal?" I was surprised at not seeing any charging taking place at the coach batteries with the engine running. Comments?

[cruising7388]

Originally Posted by gksmith

Well, it is time for my next question. First of all, I have installed new wet cell deep cycle coach batteries. They tested at 12.8 volts. And I connected the alternator cable to the engine battery cable and coach batteries upon doing the installation yesterday PM. I also purchased a battery disconnect for the engine battery and installed it this AM. As a side note, I have contacted Randy at Best Converters and have ordered one of his suggested converters--a PD4565V which is the suggested replacement for the Parallax 7435. And the Blue Sea 7622 ACR is on back order, but will be sent to my residence for future installation.

Now back to the present. Thinking that since the new coach batteries tested 12.8 volts, I would not need to plug in the shore line last night. I discovered recently, though, that I could not start my Onan generator--it would not turn over. But if I started the engine, then there was enough power to turn over the generator starter. I never had to do this before! So I began testing voltages at the batteries. First, I tested the coach batteries--they were down to 12.6 volts, but the starter battery was still at 12.8. Then I started the engine. The engine battery now registered at 14.8, as expected. But the voltage at the coach batteries remained the same, at 12.6. So I plugged into shore power. I just now checked to coach batteries (about an hour later)and they are now at 13.1 volts. So obviously the converter is doing some charging of the batteries.

So, my question is basically, "Does all of this seem normal?" I was surprised at not seeing any charging taking place at the coach batteries with the engine running. Comments?

I checked the model number (PD4565V) with Progressive and they indicate this is not a good number. For starters they say they don't make any units rated at 65 amps. They are either 60 amps or 70 amps. They do offer a 4600 series that is designed to replace in Parallax/Magnetek units with 35, 45 and 55 amp versions that includes a DC circuit board replacement.

The Onan typically gets its suds from the engine battery. When you were unable to crank the Onan, was the engine battery disconnected?

1. Confirm that the isolator is out of the picture and that you have completely bypassed it by bridging the coach batteries and the engine battery.

2. Confirm that when the engine is running, although you are getting 14.8 volts at the engine battery you still get only 12.6 volts at the newly installed coach battery terminals.

Check that the voltage where you bridged all the batteries is 14.8 volts. If it is, there is an open between your bridge and the coach batteries. They recognize the charging path from the shore power converter but they are not connected to the alternator charging path.

[gksmith]

Originally Posted by cruising7388

I checked the model number (PD4565V) with Progressive and they indicate this is not a good number. For starters they say they don't make any units rated at 65 amps. They are either 60 amps or 70 amps. They do offer a 4600 series that is designed to replace in Parallax/Magnetek units with 35, 45 and 55 amp versions that includes a DC circuit board replacement.

The Onan typically gets its suds from the engine battery. When you were unable to crank the Onan, was the engine battery disconnected?

1. Confirm that the isolator is out of the picture and that you have completely bypassed it by bridging the coach batteries and the engine battery.

2. Confirm that when the engine is running, although you are getting 14.8 volts at the engine battery you still get only 12.6 volts at the newly installed coach battery terminals.

Check that the voltage where you bridged all the batteries is 14.8 volts. If it is, there is an open between your bridge and the coach batteries. They recognize the charging path from the shore power converter but they are not connected to the alternator charging path.

Oops! I made another mistake typing in model numbers. It should have been PD4645V. Obviously typing in model numbers is not my thing! My apologies! Hopefully you agree with Randy and the site that it was a good choice for my current situation, as per email notifications, it is now at my door steps at home. I did not choose the 6200 series as it was not included in the suggested list--perhaps I should have asked further.

Per documentation with the coach and also with the generator, the Onan starts from the coach system, not the engine battery. So, evidently 12.5 volts at the coach batteries was not enough to start the Onan. And this is what truly led me to investigate the situation of the alternator not charging the coach batteries.

But, I am pleased to say that I have figured out the problem. Pursuant to the statement that there had to be an open bridge somewhere and in preparation for the future replacement of the charger and associated suggestions to make sure I had 4 gauge cabling back to the battery, I looked further in the charger area. I found a cable attached to a solenoid that had the same red tape wrapped around it as existed on the cable attached to the positive battery terminal. I was pleased to find 4 gauge identification on this cable. Also in this proximity were other 4 gauge cables, one of which had to pass through a small rectangular device. I discovered that this device had a very small rod that could be pushed into the body of the device. So I pushed the rod in, tested the voltage at the coach batteries with the engine running, and the problem was solved! Obviously this is a circuit breaker for the cable coming from the alternator and probably saved my electronics when the alternator went bad. Since the old isolator was located before the circuit breaker, it was not as fortunate and hence a diode got burned out by the 27 volts the old alternator was putting out.

I had previously seen this "device", discovered the rod, and accidentally pushed in the rod, and wondered if I had done some damage, as I expected it to act like a push button switch of some sort. I took a picture of it to post, but I never got it done. So my question now, I wonder what made the circuit breaker trip again, after this earlier resetting? But after being on a three day road trip, all has remained as expected, everything is working fine, so I feel that my problems have been solved for now! Now to start heading home!

So, during this saga, I replaced my alternator, engine battery, and both coach batteries. (A side note--I also replaced the font calipers and rotors when the brakes started a grinding noise pulling off the Interstate at my daughter's location.) I have removed the diode based isolator and will replace it with a Blue Sea ACR. I will upgrade the coach charger with the three stage PD4645 charger. And I have added a manual battery disconnect switch. I feel that my coach should now be in excellent shape for quite a while. Hopefully the future addition of the ACR and the replacement of the charger goes smoothly.

This has been a long and frustrating experience, but also a very rewarding and educational experience. I feel that I now know my coach much better and am more confident about it.

I want to express my deep appreciation to cruising7388 and Booster, as well as others that chimed in. Your patience and frequent, prompt responses were extremely helpful and gratifying! Thanks, so much!

[booster]

Thanks for the update, I think it gives a clearer sense of what actually happened in the first place. You seem to be on your way to getting it straightened out.

It does appear to have started with the alternator going to full output for whatever reason. I think it would have had to either have the field negative short to ground, or the regulator (in computer in appears) would have had to lose the voltage reference. It could have been the isolator failing causing loss of reference or the alternator itself shorting.

Once the voltage went to 27v, you were lucky that the isolator was open, or you could have lost lots of the Dodge electronics. The breaker apparently was fast enough to save the coach stuff, which is less fragile, and that half of the isolator.

The good thing is that going to the separator will mostly eliminate the loss of reference problem in the future, because the alternator stays connected to the starting battery, just like stock, as does the Dodge electronics.

Now we just need to convince you to put in a battery monitor while you are at it, and you will be in very good shape to keep track of your new system

[cruising7388]

Originally Posted by gksmith

Oops! I made another mistake typing in model numbers. It should have been PD4645V. Obviously typing in model numbers is not my thing! My apologies! Hopefully you agree with Randy and the site that it was a good choice for my current situation, as per email notifications, it is now at my door steps at home. I did not choose the 6200 series as it was not included in the suggested list--perhaps I should have asked further.

Per documentation with the coach and also with the generator, the Onan starts from the coach system, not the engine battery. So, evidently 12.5 volts at the coach batteries was not enough to start the Onan. And this is what truly led me to investigate the situation of the alternator not charging the coach batteries.

Congratulations on your well executed electrical improvements. You'll be rewarded with a lot of trouble free and irritation free miles.

Either the 46xx or 92xx lower ends will work equally well but the 4645V will fit right into into the shell of the 7345 lower end you are replacing. The 46xx series uses hard wired connections for AC power while the 9300 series is terminated in a conventional plug. Randy leans toward the 46xx because Progressive has hassled customers who cut off the plug to effect hard wiring. Electrically it has the same charging characteristics as the 9245. The difference is that the 92 series includes the pendant while the 4645V doesn't include it as standard and you have to order it as an accessory.

There are differing opinions regarding the choice of the battery that best supports starting the generator. In my opinion, the engine battery is the better choice. You are most likely to need to fire up the generator when coach batteries are well depleted and not happy addressing the generator starting demand compared to the isolated better charged engine battery. Also, a cold generator will typically demand 120 amps or so to initially crank and I think the engine flooded cell battery is a better suited for this than a deep cycle coach battery.