12v Disconnect?

I have an older RV with a Magnetek 6345 convertor.  I need a way to disconnect all the 12v power to the coach but not effect the battery charging.  I connected a remote solenoid in line with the battery connection,  before it gets to the convertor,  but if 110 power is available,  all the 12v appliances still run.  I am looking for a master cutoff switch that will kill everything 12v with one switch.  I am electrical savvy,  so any suggestions will be helpful. 

Thanks

Hi Agood1, Welcome to The RV Forum!

The battery connects to the converter output on the 12 volt fuse board inside the 6345 enclosure, so the converter will continue to feed the fuse board even if the battery is disconnected.  But this isn't a good idea - the 6345 needs the battery to provide some voltage regulation and keep surges out of your 12 volt gear.

To do what you want, you'll have to lift the positive lines that connect the battery and converter from the fuseboard, hook them together elsewhere and put a disconnect between that point and the fuse board.

But I don't recommend it - the 6345 is also notorious for boiling batteries dry if it's left connected to the batteries for long periods (several weeks or more).  Modern converters are much nicer on batteries.

Instead, I'd get a separate Battery Minder and use it to keep your batteries charged while the rig is in storage. Here's one example.

When you put the rig in storage, turn off the AC power going to the 6345 (it should be on one of the AC circuit breakers) and use the disconnect you installed to isolate the battery.  Then connect the Battery Minder directly across the battery.

You want to be careful not to run the 6345 without the battery being connected to it - it needs the battery to act as a current sink and provide some voltage regulation.  If the battery is disconnected there's nothing to stop voltage surges from getting to your 12 volt lights and appliances.

Out of curiosity, why do you want to remove 12 volt power from your rig?

Well,  I was looking for an easier way to shut down the coach.  I store it in my shop and go in and out of it a good bit.  Since it is dark in the shop,  I have to go in and turn on several lights,  find what I need and then turn off all the lights again.  I was looking for an easy way to just use one switch to turn the system on and off.  Also If I can kill all the 12v appliances,  I know there is no load on the system and draining the battery. 

I guess I could take several relays and wire them into the light circuits and just turn the lights on and off with one switch......but I had hoped I could kill everything.

You need a new converter (I'm serious about this)  On the list of good converter the Magnetek 6300 is right about..... the bottom of the list (Actually it' son the "Other" list (Not so good converters) and rather close to the top)

The one thing you do not want to do with it is leave it connected for long periods of time.

And the leads you need to disconnect are all internal to the converter itself.

That is the bad news

now the good news

The Magnetek 6300 has a charger stage, (Module) and a Power Supply stage (Module) when you plug in MOST of the 12 volt loads are disconnected automatically.. They run off the converter exclusively, and receive no battery power.  When you unplug a relay drops ,, Well IN in this case, and parallels the two power systems allowing battery power to the lights.

Some loads are "Ripple senistive" (LIke the radio for example) these are hooked direct to the battery side of the relay mentioned above.



ON the 6300's fuse block I understand there are two "Reverse protect" Fuses (30 amp) then a fuse or two that are "Battery Powered" (Filtered DC for Radio and the like) and the rest are converter powered.

THE BLUE WIRE from the converter module to the top of the fuse block, is the wire you need to "Break" to cut off all the 12 volt loads NOT connected direct to the battery. (Pull or switch the fuses that power the rest of it)

Do not disturb the 30 amp fuses.. .At least not both of them

Understood..
Here's what I am thinking to simplify things.

I put a disconnect solenoid on the incoming battery line to the convertor.  I use a switch at the front door to activate this solenoid.  So when I have the coach stored in the shop.  I will turn off the 110v breaker to the convertor and just use the battery power for the lights........from the solenoid.
I will keep a separate battery tender on the battery itself to keep it topped off.....
Any ideas why this won't work?

Also, some research popped up a battery disconnect solenoid that appears to be made for this purpose....It appears to be made by parrallax model BR100.  Anyone know anything about this?  I've looked at the diagrams, and they are confusing on how they work.


Thanks

Still sounds unnecessarily complicated to me. You don't need charging from the 6350 if you provide a separate, secondary charger.  Switch off the circuit breaker that feeds 120v to the coach or simply do not plug the coach into a wall socket and you will get no charging from the 6350. The battery will still power the lights and anything else 12v as needed and the separate charger will replace the energy as needed.

I need the AC sometimes while in the coach....so it has to be plugged into 110V.

agood1 said:

I need the AC sometimes while in the coach....so it has to be plugged into 110V.

Click to expand...

Can't you just switch the ac ON before entering the coach, and OFF again as you leave?.  Plug the extension cord powering the battery Minder into a separate non-switched 120vac source. 

There is no need to alter the converter at all.

We are missing the original point...I need to go in,  flip a switch and turn on enough lights to see.  Instead of going to each individual light and turning it on,  then turning each individual light off when I leave......I am doing a remodel on this inside and I am in and out quite a bit.  Many of my previous coaches had a master disconnect,  I was just hoping I could replicate that again on this coach.

agood1 said:

We are missing the original point...I need to go in,  flip a switch and turn on enough lights to see.  Instead of going to each individual light and turning it on,  then turning each individual light off when I leave......I am doing a remodel on this inside and I am in and out quite a bit.  Many of my previous coaches had a master disconnect,  I was just hoping I could replicate that again on this coach.

Click to expand...

Say what?

What's the difference between turning ON the 120vac, entering the coach and selecting the lighting you need (turning them on/off as desired  or leaving them all ON), and then reversing the process on the way out.

--AND-- 

Turning a DC disconnect switch ON, entering the coach and selecting the lighting you need (turning them on/off as desired  or leaving them all ON), and then reversing the process on the way out? ??? .

You have the same function AND the added benefit of not allowing the antique 6300 to boil your batteries.

How does turning on and off the 110volt power change the status of the 12v lights?....if I just kill the AC power to the coach,  the 12v lights will run off the battery until it's dead. 

Well, you have defined the problem such that there is only one solution. If you don't want to turn lights on individually then you need a 12v master disconnect, or at least a lighting master disconnect. I'd bet there is probably just one 12v circuit in the Magnetek that supplies all the interior lighting - you could probably find that one (on the bus bar in the Magnetek) and switch that.

agood1 said:

How does turning on and off the 110volt power change the status of the 12v lights?....if I just kill the AC power to the coach,  the 12v lights will run off the battery until it's dead.

Click to expand...

Sorry, I thought we already discussed that by disconnecting the battery lead and adding the simple little battery minder.  If you have to worry about the output of the 6345 (with no battery installed) causing problems, then you should immediately get rid of the converter and/or clean up the power in your storage area.  JMHO. 

I have no more suggestions or comments on the subject.

I've wired my RV exactly how you want it setup. I've got a battery cutoff switch in the cabinet next to the breaker panels. I put the charger in the battery lead before the switch and then the remaining loads after the switch.

http://i41.tinypic.com/keagpc.jpg

Mopar1973Man said:

I've wired my RV exactly how you want it setup. I've got a battery cutoff switch in the cabinet next to the breaker panels. I put the charger in the battery lead before the switch and then the remaining loads after the switch.

Click to expand...

I would hardly call your solution EXACTLY the same as the OP's, since you have a single output PD-92XX charger to begin with.  It is, however, the exact result that he wants.

Gary,  I already thought of your idea,  but the lights are on 3 different circuits,  along with some other things,  so simply switching the lighting circuit will not work......I appreciate all the replies....I guess since there is no one solution,  I will have to come up with something different.....which I am known for....I will post my results once I figure it out.

Thanks

The blue wire on the Magnatek provides 12volt power to the lights,  Water pump and other non-ripple sensitive loads... I do not think it provides power to the radio or other ripple sensitive loads.

You can switch the wire that feeds the 12v bus in the 6350. That will turn off ALL 12v power but (I think) still leave the battery charge function active. But that will turn off the fridge as well - it needs 12v power to function.

These photos on 6300 replacement show the bus wiring:

https://bestconverter.3dcartstores.com/MagnetekParallax-to-Ultra-III_ep_8-1.html

I don't know if it will help or not but you can download the 6345 schematic HERE.

Maybe I don't understand but...

In my trailer there is a DC panel in the bathroom with a push-pull on/off switch on the side.

In the off position almost all dc power is off. Smoke alarm and gas smell alarm are still on.  Battery charging continues.

Joel