Issue with the 12v system.

[Rick 2005 Dolphin 5376]

Hi all. Julia and I have been FT'ing in the Dolphin for 2 1/2 years. If there is a more reliable coach, I'd like to see it. In the last two weeks we've had an issue twice, regarding the 12v system. Last night was the second time. I noticed that the 12v lighting was a bit dim. I checked the battery voltage on the control panel, both chassis and house batteries were 11.3 volts. Under normal operation I see14.3v. The fix was the same both times. I started the genset and let it run for abour 1 hour. Turned it off and the coach re-set from genset to shore power and the batteries once again start to charge. This morning we are back a 14.3 volts. Is there something I should check or look at? Is this the beginning of battery failure? Could it be cold weather? Dirty connections? Any help would be appreciated.
Thanks in advance.

[Rick 2005 Dolphin 5376]

Hi all. Julia and I have been FT'ing in the Dolphin for 2 1/2 years. If there is a more reliable coach, I'd like to see it. In the last two weeks we've had an issue twice, regarding the 12v system. Last night was the second time. I noticed that the 12v lighting was a bit dim. I checked the battery voltage on the control panel, both chassis and house batteries were 11.3 volts. Under normal operation I see14.3v. The fix was the same both times. I started the genset and let it run for abour 1 hour. Turned it off and the coach re-set from genset to shore power and the batteries once again start to charge. This morning we are back a 14.3 volts. Is there something I should check or look at? Is this the beginning of battery failure? Could it be cold weather? Dirty connections? Any help would be appreciated.
Thanks in advance.

[Richard S.]

Rick,
If you have an automatic transfer switch it may have dirty contacts. Not sure what brand transfer switch NRV used on your coach if you have one. Mine is a ESCO brand.
http://www.escousa.net/Merchan...hootRepair102506.pdf Had a problem with mine, had to blow dirt and junk out of it.

[Mike Canter]

I believe the automatic transfer switch is for the 110v shore power to genset swap over. That is if we are talking about the same transfer switch.If the 110v transfer switch was causing the problem then you will have problems with the microwave or the TVs not working either on shore power on the genset.

You didn't say if the MH batteries where reading this low voltage after being plugged into shore power or after driving down the road. If it is after driving down the road then it would be time to get the alternator checked. If it is after being plugged into shore power then the converter should be checked.

Since the batteries charge up when on the genset indicates that the batteries and all the connections are good on the batteries.

[Rick 2005 Dolphin 5376]

Thanks for the info Richard. Where would I start to look for the transfer switch? I have no problem taking it apart to clean and or replace.

[Rick 2005 Dolphin 5376]

While on shore power: Batteries discharge to about 11v. Only has happened twice but both times in the last few weeks. By either just disconnecting all power with the power switch located at the door for a few minutes and then turning back on or by running the genset for a while and turning it off to return to shore power, the batteries will start to charge on shore power. From what has been said I'm thinking that the contacts on the contactor are dirty. By removing and re-applying power to them, they start to make contact again.

[Richard S.]

The inverter/ charger or converter/charger get power from the transfer switch. If you cant find the ATS you can un plug your shore power, plug it back in, you will hear a loud click when you plug it in. My ATS is in a storage compartment drivers side one foward of water service compartment.
When you find the ATS PLEASE disconect shore power and do not have gen set running when you remove the cover.

[wa7hra]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Richard S.:
The inverter/ charger or converter/charger get power from the transfer switch. If you cant find the ATS you can un plug your shore power, plug it back in, you will hear a loud click when you plug it in. My ATS is in a storage compartment drivers side one foward of water service compartment.
When you find the ATS PLEASE disconect shore power and do not have gen set running when you remove the cover. </div></BLOCKQUOTE>

There may be an additional circuit breaker located elsewhere for the inverter/converter circuit. Mine has such a device and it it is popped, the symptoms you described may occurr.

Bob, wa7hra

[Rick 2005 Dolphin 5376]

My converter / Charger is located in the front most, outside compartment on the passenger side. Will I find the contactor there?

[Rick 2005 Dolphin 5376]

Now that I think about it. I believe contactor is in the rear most driver side compartment. I'll investigate when I get back to casa-de-wheels.

[Richard S.]

Good Luck

[Rick 2005 Dolphin 5376]

You guys are great. Thanks for the help. Sounds like a minor problem, not a major $$$

[Mike Canter]

Again it would seem to me that if the contacts are dirty or bad in the transfer switch then the 110v appliances such as the TV's or the microwave will not work on shore or on genset power. If they are working OK then why would the transfer switch be bad? It would also be easy to read the voltage at a 110v wall outlet and see if it is correct both on shore and genset power. If correct in both then the transfer switch is probably not the cause and it maybe the converter/charger bad or a blown breaker or fuse.

[Rick 2005 Dolphin 5376]

I'd agree but isn't it weird that just a simple switch to genset or turning off and then back on again total power to rig would fix it?