I have a hypothetical question concerning DC electrical power in a diesel pusher RV. Our rig is a 96 Dynasty with a mechanical Cummins C8.3 (96 was supposedly the last year for the mechanical C8.3, then they went to computer controlled). Now what if the engines alternator failed. First you get a warning on your dash, most likely the "ALT" light would come on, or you "VOLT" light, then you would pull over and try to figure out what's causing the problem. So, let's say that you conclude that the alternator has failed, and here's where the hypothetical part comes in. When I run the Onan generator AC is supplied for the coaches AC needs, and some of that AC is converted into DC and fed into the DC system for charging the battery, running the lights, etc. So, would the Onan generator supply the DC voltage I needed to limp home until I could get the engine alternator repaired? The engines DC needs are relatively small as opposed to a gas engine, and I figured with daytime driving only it might actually work. Any inputs are much appreciated. - Tom
1996 Monaco Dynasty 36', Cummins C8.3 with Banks Stinger kit, Allison 6 speed.
All this worked very well until the day I pulled up to the ferry terminal knowing gas was cheaper on the other side. It was a wait, and I did not open the door so the head light alarm never came on. Blah, withing an hour, the chassis battery was dead. I started the generator, and blah blah, I was so low on gas, it would not stay running.
Long story was, got going and onto the ferry just in time with help from the ferry station jump start, kept the engine running for a few minutes, and all was well again.
Mike
2012 Winnebago Impulse Silver 26QP
2005 16.6 Double Eagle
2018 Jeep Wrangler JK
previously Snowbird Campers,
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Might find a friend with a meter to verify on yours.
Jerry Parr
Full-time
2005 Mandalay 40B
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Two summers ago I drove several hours with the ALT light on and drooping voltmeter as I knew my solar powered trailer will push some power forward to my truck. Made for a 2.5 hour lunch stop on schedule vs. pulling over or getting stuck waiting for a tow. Still everyone was booked so I did the repair in the O'Reily's parking lot in Gillette WY.
2001 F150 SuperCrew
2006 Keystone Springdale 249FWBHLS
675w Solar pictures back up
If the alternator is out. It still may try to disable the combining function so you would need to verify they are getting the charge. A simple jumper around the solenoid that controls that function or one car jumper cable will work but not as safely. You can either find out how to activate that solenoid mentioned or just take the wires off and bolt together or stack them up on one post if there is room. Be sure to take pictures first.
H/R Endeavor 2008
2013 Ford Edge toad
Full Timers
This post is my opinion (free advice). It is not intended to influence anyone's judgment nor do I advocate anyone do what I propose.
Sold 04 Dynasty to our son after 14 great years.
Upgraded with a 08 HR Navigator 45’...
Brian, Loretta & Daisy (Golden Retriever)
2008 Holiday Rambler Endeavor PDQ40
2014 Ford Explorer toad
Yes, absolutely, your converter, charger or inverter/charger will charge the HOUSE BATTERIES. On SOME COACHES, it also charges the CHASSIS BATTERIES-- by no means on all.
Some coaches have a "boost/combine" switch that closes a relay/solenoid so that the two banks are combined. May be an intermittent duty solenoid or constant duty one.
Some coaches have a low amp combiner (Xantrex Echo Charger for example), but likely not sufficient to keep up a chassis battery with loads like fans, lights, etc.
BUT, you can manually combine your banks. Whether at a battery isolator, battery boost/combiner solenoid or other place where you have large-gauge battery cables from both battery banks meeting at a common place. Merely take the large wire off one side and ADD IT to the other side. Presto, both banks being charged by your converter, charger or inverter/charger.
Amp output of the charging device needs to be considered. Said another way, a 30 amp converter is NOT the same as a 2000 watt inverter with 100 amp charging capability.
Brett Wolfe
Ex: 2003 Alpine 38'FDDS
Ex: 1997 Safari 35'
Ex: 1993 Foretravel U240
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Now in this day and age, you can buy a unit that will automatically charge the engine to coach. It is a microprocessor that is connected between the engine and coach Via 50 to 100 amp cables. It senses which battery is above 13 Vdc and allows the transfer of voltage.
If this is an emergency, jumper cables IF your coach battery is very close to your engine battery
Dale & Susan
DaGirls II Rv - Dakota & Tilly Traveling Companions.
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As mentioned above, "if" the generator powers some source that charges your engine batteries (mine does not) you likely will be just fine but still want to try to reduce as many other 12V draws as possible as the charging source is likely not going to put out as many amps as your engine alternator would.
What I post is my 2 cents and nothing more. Please don't read anything into my post that's not there. If you disagree, that's OK.
Can't we all just get along?
LEN
If the alternatro fails than running the gen set will merely substiute for shore power and keep both bank charged. If one does not have an echo charger or such it's a simple matter to add on.
A last ditch effort is to stick a toothpick into the battery parallel switch to keep it engaged.....been there done that..and it works well.
Dick
2002 43' DP Beaver Marquis Emerald Cat C-12 505 HP, 1600 Tq
2003 Jeep Grand Cherokee Overland ---toad
I had an alternator failure four years ago during a shake down trip to grand canyon, after an engine repair in Flagstaff
I pulled over and put a jumper cable from house positive to engine positive, and then started the Oman
And continued on our way back to flagstaff and had the alternator replaced
* This post was edited 07/11/16 08:38pm by MrWizard *
I can explain it to you.
But I Can Not understand it for you !
....
Connected using T-Mobile Home internet and Visible Phone service
1997 F53 Bounder 36s
OLYLEN wrote:
Just use jumper cables from the Coach to chassis batteries and you could go a long way. or use a cloths pin to keep the emergency start switch active. If a converter makes 12 volt supply from 120 and an inverter makes 120 from 12 volts why is a inverter/converter not the same as an inverter/charger.
LEN
Just use jumper cables from the Coach to chassis batteries and you could go a long way. or use a cloths pin to keep the emergency start switch active. If a converter makes 12 volt supply from 120 and an inverter makes 120 from 12 volts why is a inverter/converter not the same as an inverter/charger.
LEN
Symantics I often use the term charger to make it easier for the target audience to understand things.
1: Many older RV's (And some newer ones) have a simple "one way" isolator.
In this type of system when you are driving the Engine charges the house batteries but when you park, the engine battery is NOT charged by shore/generator power
If you have that type of system the answer is NO, but (you can add a single jumper wire to do the job in many cases)
2: Many modern Motor homes (Last decade or so) have a BI-Directional isolator like Mine has
In this case, if EITHER engine alternator or house converter is active, ALL batteries get charged..
And the answer is YES.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times
Older systems with insulator will require jumper like MrW did as the emergency relay is not 100 percent duty and you can't use it for long time.
Regardless generator, battery alone should allow for couple of hr of driving if you turn off unnecessary items.
When alternator failed on my Powerstroke, I drove the pickup 140 miles till I found a place with new alternators. Dual batteries still started the engine after alternator replacement.
