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Hello again!! [message #331202] Sat, 21 April 2018 21:21 Go to next message
Atom Ant is currently offline  Atom Ant   United States
Messages: 170
Registered: October 2016
Location: Austin, TX
Karma: 0
Senior Member
Hi all-

It's been a hot minute. Hope you're all well.
Haven't had much time to spend with the coach, but it's a marathon not a sprint, right?

I'm getting the urge to tinker again, and with good reason.

My coach had some " creative wiring" when I got it. When I plug her in, it charges the battery system, and things run off of that. I just realized that if the battery system doesn't charge, I got nothing. The reason I know this is because I think my charger is on the fritz, and none of they lights or house systems work without it. I know I need to rebuild the charging/inverter system, and need some guidance.

Does this beast have a system by which it runs straight off of shore power?

I need a gentle reminder of how these systems work.

Thanks in advance for your infinite patience with my dumb questions.

EDIT-

So in looking at the wiring schematic, if plugged into shore power, the only things that work are the outlets and a/c units.

Everything else runs on 12 v?





1976 Palm Beach Austin, TX

[Updated on: Sat, 21 April 2018 21:56]

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Re: Hello again!! [message #331204 is a reply to message #331202] Sat, 21 April 2018 22:43 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
Atom Ant wrote on Sat, 21 April 2018 22:21
Hi all-

It's been a hot minute. Hope you're all well.
Haven't had much time to spend with the coach, but it's a marathon not a sprint, right?

I'm getting the urge to tinker again, and with good reason.

My coach had some " creative wiring" when I got it. When I plug her in, it charges the battery system, and things run off of that. I just realized that if the battery system doesn't charge, I got nothing. The reason I know this is because I think my charger is on the fritz, and none of they lights or house systems work without it. I know I need to rebuild the charging/inverter system, and need some guidance.

Does this beast have a system by which it runs straight off of shore power?

I need a gentle reminder of how these systems work.

Thanks in advance for your infinite patience with my dumb questions.

EDIT-

So in looking at the wiring schematic, if plugged into shore power, the only things that work are the outlets and a/c units.

Everything else runs on 12 v?

Adam,

That is substantially correct.

The only other thing that is powered by AC from either shore power or the generator is the converter/charger that should be charging the house bank and powering all the 12v DC things.

Again, the dumb questions are those that you refuse to ask.
The reason that I "over answer" questions is that others are reading that may not have as much understanding as you posses.

So, please, if you are not sure, assemble your questions and ask.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Hello again!! [message #331206 is a reply to message #331204] Sun, 22 April 2018 00:07 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Matt Colie wrote on Sat, 21 April 2018 22:43
Atom Ant wrote on Sat, 21 April 2018 22:21
Hi all-

It's been a hot minute. Hope you're all well.
Haven't had much time to spend with the coach, but it's a marathon not a sprint, right?

I'm getting the urge to tinker again, and with good reason.

My coach had some " creative wiring" when I got it. When I plug her in, it charges the battery system, and things run off of that. I just realized that if the battery system doesn't charge, I got nothing. The reason I know this is because I think my charger is on the fritz, and none of they lights or house systems work without it. I know I need to rebuild the charging/inverter system, and need some guidance.

Does this beast have a system by which it runs straight off of shore power?

I need a gentle reminder of how these systems work.

Thanks in advance for your infinite patience with my dumb questions.

EDIT-

So in looking at the wiring schematic, if plugged into shore power, the only things that work are the outlets and a/c units.

Everything else runs on 12 v?

Adam,

That is substantially correct.

The only other thing that is powered by AC from either shore power or the generator is the converter/charger that should be charging the house bank and powering all the 12v DC things.

Again, the dumb questions are those that you refuse to ask.
The reason that I "over answer" questions is that others are reading that may not have as much understanding as you posses.

So, please, if you are not sure, assemble your questions and ask.

Matt

To add a little to Matt's post. Somewhere in that coach should be a converter. It takes 120VAC and converts it to 12VDC. Then the 12 VDC is supplied to the house battery (for charging) and to the 12 VDC fuse panel which supplies all of the interior lighting etc. inside the coach. Please note that the interior lights over the passenger's and driver's heads and anything in the dash are NOT on the house 12VDC system. They are powered by the engine battery and engine driven alternator.

So the first thing I would be looking for is that converter and seeing if it is turned on and not outputting 12 VDC. I did not check the model of your coach before I started typing so I did not to tell you where the converter is. In most GM 26 upfitted coaches it is located in a cabinet across from the bath module.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Hello again!! [message #331224 is a reply to message #331206] Sun, 22 April 2018 11:30 Go to previous messageGo to next message
Atom Ant is currently offline  Atom Ant   United States
Messages: 170
Registered: October 2016
Location: Austin, TX
Karma: 0
Senior Member
Thanks guys-

I haven't given the coach much thought in the past year, and leave it plugged into shore power cause on occasion we have someone visit and it's a good place to bunk.

BUT-

It's got some quirks. What is currently charging the aux battery is a Stanley battery charger plugged into one of the outlets.

It works, but not ideal. I plan on re building the charging system, but need to save some nickels first.

I think this charger is on the fritz, so the house aux battery isn't charging, hence my question. I leave an led light on to let me see that it's all working and it wasn't on.


1976 Palm Beach Austin, TX
Re: Hello again!! [message #331226 is a reply to message #331224] Sun, 22 April 2018 11:40 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Atom Ant wrote on Sun, 22 April 2018 11:30
Thanks guys-

I haven't given the coach much thought in the past year, and leave it plugged into shore power cause on occasion we have someone visit and it's a good place to bunk.

BUT-

It's got some quirks. What is currently charging the aux battery is a Stanley battery charger plugged into one of the outlets.

It works, but not ideal. I plan on re building the charging system, but need to save some nickels first.

I think this charger is on the fritz, so the house aux battery isn't charging, hence my question. I leave an led light on to let me see that it's all working and it wasn't on.

OK I see you have a 76 PB. The converter is located in the second cabinet up directly across from the bath module. Does the converter have 120VAC power to it? If it does, is the converter putting out 12 VDC.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Hello again!! [message #331232 is a reply to message #331226] Sun, 22 April 2018 12:57 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
Senior Member
If your converter is what we call affectionately a 'buzz box' (OEM battery charger)(color is generally blue), remove it from the coach. They are very old designs noted for ruining batteries. Replace it with a modern three stage design, Iota, Progressive and others make what you need. Search this site for model numbers. JmK has them in stock and a good source for everything GMC.
Tom


2012 Phoenix Cruiser model 2552 KA4CSG
Re: Hello again!! [message #331238 is a reply to message #331202] Sun, 22 April 2018 13:23 Go to previous message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
However, if you have an original 12V setup - made by Tripp Lite in both of my 76s, replace it with a modern charger/converter but don't toss it. It's an excellent 12V bench supply.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
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