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Topic: Gen switch...yes another question.. (Read 455 times) previous topic - next topic

Gen switch...yes another question..

Getting ready to park coach for a couple weeks...If I leave the ON switch on Generator do I leave the main batt switch on or off??? And do I leave boost switch ON..?

To you shaking your heads...I apologize...lol
2001 U320 42 tag with two slides
Build number 1583
Love this forum for all of it's help and members

Re: Gen switch...yes another question..

Reply #1 –
Define "park".  Do you have power available to plug in at all?  How often will you be checking on the coach?

Do NOT leave the boost switch if you cannot check on the coach at least every couple of days - you risk running down both the chassis and the house batteries if you don't have a source to keep the house batteries charged.  All the boost switch does is connect the two battery banks; it does not care which direction the electrons and holes flow  ;)
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Gen switch...yes another question..

Reply #2 –
If you can plug in to power, which will keep the batteries charged, you can make the argument to leave the boost switch on.  Many on here would tell you not to, however.

If you can plug in to power, tough to go wrong, and whether or not you leave specific things on or off, you'll be fine to come back in a few weeks.

I don't know whether the battery cutoff would prevent the generator from charging the batteries.  But that's easy to test.  Cut the power, hit the generator switch, and check the display.

If you're only gone a few weeks (and you have a reasonably limited parasitic draw), your batteries should be fine when you get back even if you're unplugged, provided you hit the battery cutoff.  If it will be in an isolated area, leaving the autostart on the generator isn't the worst idea.  If will be garaged or near other houses - that might not be ideal.

The most important point has already been made by Michelle.  DO NOT leave the boost switch on if the coach is not plugged into shore power.  You will have all dead batteries when you get back.

As an alternative - if you are leaving unplugged for longer periods - and don't have to worry about cold weather, pipes freezing, etc., just consider manually disconnecting the house and engine battery cables before you leave.  Won't have to worry about parasitic draw then!  If they are good batteries and are fully charged when you leave - they'll still be fine after a few weeks.
James
w/ DW Erin, sons Gideon and Tobias, cats Oscar & Oliver
Fulltime 1999 U270 34' #5508

Re: Gen switch...yes another question..

Reply #3 –
I'm sorry for not explaining...no shore power when parked..but I do have room to let the generator run. It's covered on roof and nose and the rear of coach is open to air. It's in a storage facility.
2001 U320 42 tag with two slides
Build number 1583
Love this forum for all of it's help and members

Re: Gen switch...yes another question..

Reply #4 –
Mike,

One reason leaving the "boost" switch on is not recommended is because your starting batteries and your coach batteries are banks of differing AH ratings/sizes, and possibly different construction (wet cell, gel, AGM, lithium).

When charging batteries the batteries in a bank should be the same amp hour size/rating and of the same construction so that they are not over charged, undercharged, or damaged by incorrect voltage levels during the charge cycle.

When the coach is running down the road the batteries are being charged by the alternator rather than the generator.  The battery isolators built into the coach, as well as the alternator sensing circuit, takes care of charging issues.

For storage consider one of the following:
- for the coach batteries use the coach battery disconnect switch to disconnect them and ensure no drains while in storage.
- for starting battery purchase a terminal mounted battery disconnect switch and mount it to the terminal with the charge wire on it.
- purchase a small solar panel and charge controller for the systems needing to be maintained.  Get a long length of wire and put the solar panel on the facility roof or in the sun in some fashion.

Another downside about leaving the generator going unattended for several weeks is that you have no way to monitor the fuel level.  The generator's dip tube that supplies fuel will stop when the tank is down to the last quarter.  If your generator fuel line starts to suck air you will need to reprime it when you fill up.

Chris

Re: Gen switch...yes another question..

Reply #5 –
generator exhaust is at front of coach- I think you said that end of coach was enclosed? That might be an issue.....
Tim Fiedler    2025 LTV Unity MBL on Order
2000 Chevy Tracker 2 Door Convertible 4WD Now lifted 4.5"
1985 Citroen 2CV6 Charleston
Murphy Rebel on wheels with 175HP Titan
Cessna P337
1980 48' Westport MY (!/4 Share)

Re: Gen switch...yes another question..

Reply #6 –
you guys are so great...some is hard to grasp but I'm learning as I read. I will just park it and turn main switch off and turn the secondary air compressor off. Should be good. I haven't put 20 miles since I bought it...just fixing and playing and learning..gotta sell the old coach now..that's the priority.
2001 U320 42 tag with two slides
Build number 1583
Love this forum for all of it's help and members

Re: Gen switch...yes another question..

Reply #7 –
Quote from: Mike Minegar –
you guys are so great...some is hard to grasp but I'm learning as I read. I will just park it and turn main switch off and turn the secondary air compressor off. Should be good.

The aux compressor will still run to keep the slide bladders inflated.  You'll need to both shut off the leveling AND remove the in-line fuse to keep it from running.  (or find some way to remove power from it completely)

Be sure to shut off the 12V at the door - that will minimize drain on the house batteries.

Your LP and CO monitors and a few other things cannot be shut off and will be a small drain.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Gen switch...yes another question..

Reply #8 –
Quote from: Numbers –
- for starting battery purchase a terminal mounted battery disconnect switch and mount it to the terminal with the charge wire on it.
All good suggestions, but, I would disagree with this one. Engine starting current can reach 1000+ amps on a cold morning. I would not recommend putting a switch in the starting battery circuit.
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Gen switch...yes another question..

Reply #9 –
Quote from: prfleming –
All good suggestions, but, I would disagree with this one. Engine starting current can reach 1000+ amps on a cold morning. I would not recommend putting a switch in the starting battery circuit.
Unless the switch is rated for that amperage range...not saying there is one.
Mike and Mari
'98  36 270 WTFE
Build #5272
Club #17504

Re: Gen switch...yes another question..

Reply #10 –
Right, there are high current rated battery switches, that can "handle" 1000 amps. But any switch introduces some contact resistance, and adds the resistance of 2 additional terminal lugs in the circuit. I know some have done this, and seem happy with the results.
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B