2005 DolphinLX battery problem.

[KentM]

Recently, while on the last leg of a 4500 mile trip through the north and west, I discovered that the engine driven alternator was not charging the coach batteries. I monitor the coach batteries closely as I run the inverter while in route to operate the refrigerator. After getting settled at the final stop, I discovered what appeared to be a faulty interconnect solenoid on the power panel that is located in the compartment under the pass. seat next to the inverter/charger. I concluded this since the coil terminals had 12vdc on them and the contacts showed about three volts across them. With a solenoid of that type , there should be very little if any drop across the contacts when it is energized.
I consulted NRV and was told that I would just have to replace the entire panel to the tune of nearly $400. I just could not justify throwing away all of the "good" components that had nothing to do with this issue. I removed the solenoid and found that the exact part is available from several sources on line. Places like Allied Electronics and others carry the part in the $20 category. It is a simple solenoid relay rated at 80amps with a 12vdc coil that is rated for continuous use. Continuous use is very important here. The unit I used was made by "White-Rodgers #70-902". I am sure they are others but at least I did not have make any changes to the mounting or connections bars.
One word of caution here. If you are not familiar with this kind of work, then get someone who is to do it for you. While 12 volts may not be hazardous, it will be if you short out the batteries. You can start a fire that will be tough to put out. I ALWAYS disconnect both negative battery terminals completely before doing any work in this area.
Once the solenoid is replaced, you can check the unit by turning off the inverter/charger. Monitor the two battery voltages and when they both drop below 12.6 volts, the solenoid will open. This feature prevents one system from draining both batteries. When the solenoid is open, you can also check the emergency start switch on the dash. Pressing this switch should energize the solenoid long enough for you to start either the engine or the generator.
After the solenoid de-energizes, apply a charging source, either start the engine or turn the inverter charger back on. As the voltage rises, it will cause the solenoid to close and then the voltage on both batteries will begin to equalize. As they both get to the fully charged state, the solenoid will open until one of the systems drops in voltage again.

[KentM]

Recently, while on the last leg of a 4500 mile trip through the north and west, I discovered that the engine driven alternator was not charging the coach batteries. I monitor the coach batteries closely as I run the inverter while in route to operate the refrigerator. After getting settled at the final stop, I discovered what appeared to be a faulty interconnect solenoid on the power panel that is located in the compartment under the pass. seat next to the inverter/charger. I concluded this since the coil terminals had 12vdc on them and the contacts showed about three volts across them. With a solenoid of that type , there should be very little if any drop across the contacts when it is energized.
I consulted NRV and was told that I would just have to replace the entire panel to the tune of nearly $400. I just could not justify throwing away all of the "good" components that had nothing to do with this issue. I removed the solenoid and found that the exact part is available from several sources on line. Places like Allied Electronics and others carry the part in the $20 category. It is a simple solenoid relay rated at 80amps with a 12vdc coil that is rated for continuous use. Continuous use is very important here. The unit I used was made by "White-Rodgers #70-902". I am sure they are others but at least I did not have make any changes to the mounting or connections bars.
One word of caution here. If you are not familiar with this kind of work, then get someone who is to do it for you. While 12 volts may not be hazardous, it will be if you short out the batteries. You can start a fire that will be tough to put out. I ALWAYS disconnect both negative battery terminals completely before doing any work in this area.
Once the solenoid is replaced, you can check the unit by turning off the inverter/charger. Monitor the two battery voltages and when they both drop below 12.6 volts, the solenoid will open. This feature prevents one system from draining both batteries. When the solenoid is open, you can also check the emergency start switch on the dash. Pressing this switch should energize the solenoid long enough for you to start either the engine or the generator.
After the solenoid de-energizes, apply a charging source, either start the engine or turn the inverter charger back on. As the voltage rises, it will cause the solenoid to close and then the voltage on both batteries will begin to equalize. As they both get to the fully charged state, the solenoid will open until one of the systems drops in voltage again.

[Rick 2005 Dolphin 5376]

Nice write up. I have only used my inverter a few times. Once that I recall, I wanted to make coffee at apit stop we made for lunch. Turned on the inverter and started to look for AC. None could be found unless I wanted to plug Mr. Drip in to the 110 outlet in the footwell of the passenger side front. I too have a 2005 Dolphin. Our's is a 5376, nicely optioned. Now I read here that the fridge runs on the inverter? While under way we use Propane for that and the generator for making coffee. I gotta wonder how much of my inverter is working and where I should expect to see AC when I'm using it.

[M&EM]

Here may be several situations where that solenoid will be seeing more then the 80 amps rating nearly continuosly(more then 5-10 minutes).

1. If the coach batteries are very run down say much more then 50%, high bulk charge current will be supplied by the alternator for some time.

2. If an inverter is used to run- say a microwave/toaster etc. while driving, then the invertor will likely be drawing at >150amps from coach batteries supplying that inverter. At the same time, the alternator will be trying to maintain coach battery voltage with a very high current flow thru the solenoid.

Any combination of the two above situations.

After a long dry camp spell when I know my 6 golf cart batteries are nearing 50% state of charge, I will run the generator to allow inverter/charger to replace much of the bulk charge before starting the the engine. This not only shortens final bulk charge, but also gets to a lower level of charge current sooner.

It is also possible to just let the generator provide recharge via the inverter/charger for an hour or so at the beginning of the days travel. This is not a bad thing especially if additiona a/c cooling is needed or for removing engine load as in hilly hot country.

Marty

[KentM]

For Rick,
Your inverter is wired just like mine. The inverter (1000w) is wired to the outlet at the passengers foot, all of the tv/dvd stuff including the bedroom, and the ice maker. In my configuration, I connected the refrig together with the ice maker and run them both on ac while underway. The AC connectors are located in the wall behind the refrig and can be accessed through the removable cover on the outside. That way I don't worry about having a fire going when I pull in for fuel. When I am boondocking and want to make coffee, I plug a good cord into the passenger outlet and run it back to the coffee pot in the kitchen area.
If your rig has the 2000w inverter, it is wired completely differently.
My inverter draws about 50 amps to run the refrig and about 70 amps to run the coffee pot.

[Rick 2005 Dolphin 5376]

Thanks for that. I do have a 1000 watt inverter. Sounds like mine is wired like yours. Good info!

[vacation on wheels]

Kent, nice write-up. I went on-line to purchase the same White-Rodgers model and found out that your model 70-902 has been replaced by a part number 70-111224. I ordered the new part and when I checked my panel on my 2003 Dolphin LX with a 2000 inverter set-up the original solenoid had the part number 70-111224.
My question is, did you just carefully remove the screws that hold the circuit board in place and then reach behind the board to replace out the bad solenoid? I am assuming that you didn't have to remove each wire from the board. I was going to try to replace my faulty solenoid this week and I would love to hear how you did the change-out.

[M&EM]

VoW,

Can you tell from any documentation of the 70-111224 part whether the continuous current rating is higher then the 70-902?.

Marty

[vacation on wheels]

According to the White-Rodgers web site, its 80amps continuous and 400 amps in-rush. Any help out there for installation procedures?

[M&EM]

VOW,
I took a look at my control board again today and I see that the WR solenoid has both of the numbers that are posted in the above posts. I haven't removed mine yet but it looks pretty straight forward.

Just make sure both coach and chassis batteries are disconnected at the batteries before you start.

Looks like 4 cap bolts connect the control board battery flow paths(JP1,JP2,JP3 & CB2) to the solenoid and battery disconnect relay buss bars.
After removing those, there are 5 screws that attach the the control board to standoff posts that would need to be removed.
There appears on mine, to be enough slack on the attached connectors to the board to allow the board to to swing away and provide access to the solenoid for r&r.

Hope this helps.

Marty

[vacation on wheels]

The 3 Phillip head screws that attach the top of the circuit board to the backing plate are REALLY difficult to remove. I would suggest that you run down to Lowe's and buy a new, high quality Phillips screw driver so you don't strip the head. I have two of the three off and can't get the last one off. It is really frustrating when one screw is delaying the repair!

[vacation on wheels]

I was finally able to get the last screw off the top of the circuit board. The screws are crimped on after being screwed into the board. The rest of the change-out is straight forward. I am at a campground now and won't be able to tell how the solenoid is functioning until we are on the road. Happy travels to all!