No 12V unless generator running

[Royalt1]

Next electrical issue

We are boondocking for the night and need a little heat. I started the 6k Onan and ran some heat. When I shut off the genny the 12V system shut off with it and now I only have lights if the genny is on. House batteries read 12.8. Checked all the fuses I could find.
???????

[Royalt1]

Originally Posted by Royalt1

Next electrical issue

We are boondocking for the night and need a little heat. I started the 6k Onan and ran some heat. When I shut off the genny the 12V system shut off with it and now I only have lights if the genny is on. House batteries read 12.8. Checked all the fuses I could find.
???????

Sorry. 2015 Four Winds 35SB Super C.

[Beau388]

Most likely it is the store/use switch (or master power on later coaches) tripped into the store position. Also there is a 50 amp circuit breaker in the house battery compartemnt that protects the cable from the house batteries to the power center. Not likely but it could be tripped if you were running the furnace when you killed the generator. At any rate you nave lost power from the house battery bank to the power center.

[Royalt1]

Originally Posted by Beau388

Most likely it is the store/use switch (or master power on later coaches) tripped into the store position. Also there is a 50 amp circuit breaker in the house battery compartemnt that protects the cable from the house batteries to the power center. Not likely but it could be tripped if you were running the furnace when you killed the generator. At any rate you nave lost power from the house battery bank to the power center.

Thanks Beau388. I have tried the use/store switch and will look for the breaker in the battery compartment at first light. I don't remember seeing one. Just a fuse on the way to the inverter.

[Royalt1]

Ok. I have 12v on the left but not on the right. What is this?
If i jumper around it the lights come on.

[16ACE27]

Originally Posted by Royalt1

Ok. I have 12v on the left but not on the right. What is this?
If i jumper around it the lights come on.

That is a latching relay, may be controlled by your USE/STORE switch.

Does it move when you operate the switch (make noise)?
Is the fuse good in the little red fuse holder?

[gnach]

Originally Posted by Royalt1

Ok. I have 12v on the left but not on the right. What is this?
If i jumper around it the lights come on.

That is your USE/STORE or MASTER POWER latching relay. "RV Custom Products Latching Relay RVC1002" A very TEMPORARY fix (before you replace it) is to put both red cables together on one side. Is there 12v on the lower terminals? Those 2 wires go to your USE/STORE momentary contact switch. What is that inline fuse for? It's on the live side.
"The RV Custom Products Latching Relay RVC1002 allows user/service technicians to disconnect Chassis/Coach batteries for storage or service. These high tech units do not draw current in either the “ON” or “OFF” position."

[Royalt1]

Originally Posted by Royalt1

Ok. I have 12v on the left but not on the right. What is this?
If i jumper around it the lights come on.

Ok. Its the battery insulator relay. I assume the two wires (yellow/ yellow black) are the coil voltage and they are dead. They disappear into the frame and I don't see them in the battery compartment. I'll call Thor now.

[Trkyte@msn.com]

Remember where that in line fuse is. If Like mine, it is the radio keep alive power. It took me a full day to find mine when I blew it with my fat fingers!

[Royalt1]

Originally Posted by gnach

That is your USE/STORE or MASTER POWER latching relay. "RV Custom Products Latching Relay RVC1002" A very TEMPORARY fix (before you replace it) is to put both red cables together on one side. Is there 12v on the lower terminals? Those 2 wires go to your USE/STORE momentary contact switch. What is that inline fuse for? It's on the live side.
"The RV Custom Products Latching Relay RVC1002 allows user/service technicians to disconnect Chassis/Coach batteries for storage or service. These high tech units do not draw current in either the “ON” or “OFF” position."

Tony at Thor tech support helped me greatly. For an unknown reason the solenoid at the batteries did not connect once the gen/shore power was removed. So I never went back on battery. I triggered it with a jumper and it stayed switched. He sent me some schematics so I've got reading to do. Got on my way, everything's working at the next stop, so I await the next electrical issue!
Thanks everyone.

[writchie]

Might have the same problem here on my 2016 Thor Chateau 31L. I was boondocking and recharging the house batteries off of the generator each day. At some point, either the Use / Disconnect switch or the Relay failed … the house batteries drained 100% and would not be recharged either by generator or shore power. I pulled the house batteries and recharged / tested them with an actual charger. I also tested the voltage coming out of the converter while connected to shore power. It’s either a bad Use / Disconnect switch or a bad Relay. A replacement switch was only $15, so I ordered it and it is on its way. For the Relay (RV Custom Products RVC-1002), how exactly did you “use a jumper” to trigger the Relay to get it working again?? I can try that out to see if I can get it to fire back into the proper position, however I don’t know which connections to jump from or jump to. When I try to use the Use / Disconnect Switch, there used to a be a loud audible click that I would hear from the Relay switching on or off. I don’t hear that loud audible click any longer when I push the switch, so maybe the Relay is stuck??? Thanks …

[16ACE27]

Originally Posted by writchie

Might have the same problem here on my 2016 Thor Chateau 31L. I was boondocking and recharging the house batteries off of the generator each day. At some point, either the Use / Disconnect switch or the Relay failed … the house batteries drained 100% and would not be recharged either by generator or shore power. I pulled the house batteries and recharged / tested them with an actual charger. I also tested the voltage coming out of the converter while connected to shore power. It’s either a bad Use / Disconnect switch or a bad Relay. A replacement switch was only $15, so I ordered it and it is on its way. For the Relay (RV Custom Products RVC-1002), how exactly did you “use a jumper” to trigger the Relay to get it working again?? I can try that out to see if I can get it to fire back into the proper position, however I don’t know which connections to jump from or jump to. When I try to use the Use / Disconnect Switch, there used to a be a loud audible click that I would hear from the Relay switching on or off. I don’t hear that loud audible click any longer when I push the switch, so maybe the Relay is stuck??? Thanks …

You can jumper the large terminals to bypass the switch.
You can apply 12 VDC to the small terminals to see if the relay will operate. Apply the voltage in one direction and it will move one way: apply in the opposite direction to move it the other way.

[Chateau_Nomad]

Please educate me... I know relays are generally used for power switching... using a low current to energize a relay - which connects a high current circuit.

What is the purpose of a latching relay in a motorhome battery disconnect? My class C simply uses a Blue Seas rotary disconnect wired inline on the positive cable.

What am I missing? What is the purpose of a latching relay beyond connecting/disconnecting house batteries?

[Beau388]

Originally Posted by Chateau_Nomad

Please educate me... I know relays are generally used for power switching... using a low current to energize a relay - which connects a high current circuit.

What is the purpose of a latching relay in a motorhome battery disconnect? My class C simply uses a Blue Seas rotary disconnect wired inline on the positive cable.

What am I missing? What is the purpose of a latching relay beyond connecting/disconnecting house batteries?

Convenience is the reason. In many RVs, the house batteries are not located near the entrance door. Take a 45 ft diesel pusher with the batteries located next to the transmission and the entrance door is in front of passenger's seat. The power center is on the wall of the mid bath. Putting a manual battery disconnect in the locked battery compartment in the rear would be less than convenient. The latching relay has became a luxury accessory like the inverter, ATS, power ports and USB ports. Why to you need several Firefly touch panels in a 30 ft hall or a full wall slide on a 40 ft coach?


You loose a lot of structure when you remove the entire wall. Two smaller slides add a wall in the missing structure and don't materially reduce the floor space. The reason for a full wall slide is they look more roomy, so the coach sells better. It has nothing to do with functionally.



If you are driving a 24 foot box, the manual battery disconnect makes sense. I had a 22ft UltraVan class A for many years. It had two manual battery disconnects, one for each battery. The switches were on the bed surround. Fortunately that was only 11 feet from the front door and inside.

[16ACE27]

Originally Posted by Chateau_Nomad

Please educate me... I know relays are generally used for power switching... using a low current to energize a relay - which connects a high current circuit.

What is the purpose of a latching relay in a motorhome battery disconnect? My class C simply uses a Blue Seas rotary disconnect wired inline on the positive cable.

What am I missing? What is the purpose of a latching relay beyond connecting/disconnecting house batteries?

The latching relay does the same thing as the manual disconnect, rotary or knife switch types, except it is operated remotely with a momentary switch. It does it using an electromagnet to change state just like a relay or solenoid EXCEPT the electromagnet just shifts the main contact state and it stays in the new state without having to keep power applied to the electromagnet - so no constant battery drain like the Trombetta solenoid.

[unsichtbarre]

We had similar issues on are 2016-24 Sr and I found loose wires where the use/store switch connected to circuit breakers before the actual relay. Tightened everything up and it has worked since.