House Battery Wiring

D

d c *mac* macdonald

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Nov 22, 2009
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I have installed the slide-out battery tray from Jim K and
a pair of 6V golf cart batteries and all new wiring. I also
have installed the PD 9245C charger/converter. I have checked
the isolator with my Fluke 77 Digital Multimeter in the Diode
Check mode and since it showed a one-way voltage drop of
approximately .51 - .52 Volts from center terminal to the
upper and lower terminals, I assume it is good. I have also
installed the Yandina combiner.

Now problem(s) have reared their ugly heads.

I have NO charging of either starting or house batteries
from the PD 9245. The output measures at ~ 14.3 VDC.

The engine charging system is charging both batteries. The
voltage on both battery banks from the engine-driven system
is running at or a bit above 15 Volts. I am thinking that
this might be a NOT good thing!

However, in preparing to back into the house from the chilly
temp in the driveway, I heard a motor running AFTER I had
turned the engine off. It was the heater blower! I did find
that the heater works, though! (;
 
Note quoted because the post is long.

Mac,

If the lights work from the house battery, then the problem is at the converter. If I were you, I would completely remove the old converter and put in new (at least 10awg) wires from the 9245 to both that fuse panel and a known good ground. 10 is actually OK as the 45 amp max won't be there that long, but more copper is always better.

It sounds like something that should not be is powering the cab HVAC fan. I can't begin to tell you where to look.

I have to go, I'll look in later and see if anybody has filled in.

Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumière (say show-me-air) Just about as stock as you will find
SE Michigan - Twixt A2 and Detroit
 
I'm back....

You have confirmed that the isolator is good...
I am a little suspicious here because 0.51 is a little too good.

I have NO IDEA what you unplugged to stop the blower.
There is a wire that is supposed to from the from the alternator through a relay (this may be the relay you found) to the blower fan to run it at high speed only when the engine is running. I can't immediately identify how this could fail and give you the result you have. With the engine off and the ignition (accessory actually) off, there should be no power at that relay at all. So, I still don't know what happened there.

Could what ever is wrong here be why the alternator output was high? As I have no guess what is actually going on, I just can't answer that. I would have to say it is a reasonable bet because something is definitely mis-connected.

As to 15.0+ from the engine system, that is a bit high, but not disastrously so. With the other PO induced issues, it could just be the misplaced sense lead for the alternator. It could also be the that the alternator's regulator has failed. That is easy to test. Put your 77 (I love that instrument) across the output post and the frame of the alternator. Look at the book (X7525-pg 6y-22, fig 25) there is a place to jab in a screw driver that will ground the field and make the alternator go to full output. Well, if the meter doesn't jump up when you do that, then the regulator isn't controlling it.

That the banks were both below 12 could indeed have been part of the high output from the alternator, but more will have to get identified before I would make a bet.

Back to the PD.. If the house lights work with the engine off and no shore power, then the house bank is working and connected to the buss bar on the fuse panel. The positive lead of from the PD9245 should also be there. If the ground is good, then the PD should be charging the house bank when AC is available.

Well, I'm done. If you can identify anything else, I'll try again.

Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumière (say show-me-air) Just about as stock as you will find
SE Michigan - Twixt A2 and Detroit
 
My 12-Volt Electrical System diagram shows a #6 from converter
(my PD with old converter removed) to the fuse panel and a #10
from there to a "Rear Battery Junction."

I have no idea as to the location of this "junction" but I see
NO connection in my coach from the fuse panel common point to
anything other than the PD converter.

Basically, I find ZERO path for the converter to send charging
voltage to the house battery bank.

Looking at the schematic I note a square block that contains a
12 Volt Cranking Battery, Aux Bat Switch, Battery Separation
Diodes (Isolator???), Engine Generator, and a Battery Pickup
Junction. These items, I presume, all reside in the engine
compartment.

I note that a #0 Red conductor should run from one terminal on
the Aux Bat Switch to the Rear Battery Junction which should be
connected by a #10 Red conductor to one terminal of the isolator.

A #1 Black conductor is shown from the Rear Bat Junction to a
60 Amp breaker that is paralleled to the Aux Battery Switch.

I guess it is possible that I did not get all the cables
in the house battery compartment hooked up correctly.

With no labels on the various conductors, this will probably be
somewhat of a wild goose chase for this novice!

Obviously, I need to come up with a #6 conductor to connect the
PD 9245 to the fuse panel.

Hopefully, the forecast of sunny and a high of 59F for tomorrow
will provide a bit less than miserable weather for trying to get
a handle on all of this mess.

Coach lights work, but it's anybody's guess as to what path the
electrons are taking through the coach!

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ex-Palm Beach, 76 ~ ~ ~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
_______________
*[ ]....[][ ][]\
*--OO---[]---O-*






> To: gmclist
> From: matt7323tze
> Date: Sun, 22 Jan 2012 12:56:29 -0600
> Subject: Re: [GMCnet] House Battery Wiring
>
>
>
> Not quoted because the post is long.
>
> Mac,
>
> If the lights work from the house battery, then the problem is at the converter. If I were you, I would completely remove the old converter and put in new (at least 10awg) wires from the 9245 to both that fuse panel and a known good ground. 10 is actually OK as the 45 amp max won't be there that long, but more copper is always better.
>
> It sounds like something that should not be is powering the cab HVAC fan. I can't begin to tell you where to look.
>
> I have to go, I'll look in later and see if anybody has filled in.
>
> Matt
> --
> Matt & Mary Colie
> '73 Glacier 23 Chaumière (say show-me-air) Just about as stock as you will find
> SE Michigan - Twixt A2 and Detroit
 
Mac,

I think you'll find that the "Rear Battery Junction" on the living area 12
VDC wiring diagram is the same point as the "Living Area Battery Pickup
Junction Block" on the chassis 12 VDC diagram. And you'll find that point
mounted on the beltline longitudinal member behind the living area
electrical panel.

Likewise, the items you report being in a box on the living area diagram
are also on the chassis diagram, which makes their connections more clear.
The "battery separation diodes" are, indeed, the isolator.

Remember that the rear batteries feed forward to the "rear battery
junction" through a large CB (the 60A one you noted) and that it's
paralleled by a solenoid relay, like that on the passenger firewall. When
Boost is used, the current requirement may exceed the 60A rating of the CB,
so it's temporarily bypassed by the relay, activated by the Boost switch.

Hopefully this hard-won knowledge help you diagnose the problem. :-)

Ken H.

>
> My 12-Volt Electrical System diagram shows a #6 from converter
> (my PD with old converter removed) to the fuse panel and a #10
> from there to a "Rear Battery Junction."
>
> I have no idea as to the location of this "junction" but I see
> NO connection in my coach from the fuse panel common point to
> anything other than the PD converter.
>
> Basically, I find ZERO path for the converter to send charging
> voltage to the house battery bank.
>
> Looking at the schematic I note a square block that contains a
> 12 Volt Cranking Battery, Aux Bat Switch, Battery Separation
> Diodes (Isolator???), Engine Generator, and a Battery Pickup
> Junction. These items, I presume, all reside in the engine
> compartment.
>
> I note that a #0 Red conductor should run from one terminal on
> the Aux Bat Switch to the Rear Battery Junction which should be
> connected by a #10 Red conductor to one terminal of the isolator.
>
> A #1 Black conductor is shown from the Rear Bat Junction to a
> 60 Amp breaker that is paralleled to the Aux Battery Switch.
>
> I guess it is possible that I did not get all the cables
> in the house battery compartment hooked up correctly.
>
> With no labels on the various conductors, this will probably be
> somewhat of a wild goose chase for this novice!
>
> Obviously, I need to come up with a #6 conductor to connect the
> PD 9245 to the fuse panel.
>
> Hopefully, the forecast of sunny and a high of 59F for tomorrow
> will provide a bit less than miserable weather for trying to get
> a handle on all of this mess.
>
> Coach lights work, but it's anybody's guess as to what path the
> electrons are taking through the coach!
>
> ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
> ~~ ~ D C "Mac" Macdonald ~ ~~
> ~ ~ Amateur Radio - K2GKK ~ ~
> ~ ~ USAF and FAA, Retired ~ ~
> ~ ~ ~ Oklahoma City, OK ~ ~ ~
> ~~ ~ ~ "The Money Pit" ~ ~ ~~
> ~ ~ ~ ex-Palm Beach, 76 ~ ~ ~
> ~ www.gmcmhphotos.com/okclb ~
> ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
> _______________
> *[ ]....[][ ][]\
> *--OO---[]---O-*
>
>
>
>
>
>
> > To: gmclist
> > From: matt7323tze
> > Date: Sun, 22 Jan 2012 12:56:29 -0600
> > Subject: Re: [GMCnet] House Battery Wiring
> >
> >
> >
> > Not quoted because the post is long.
> >
> > Mac,
> >
> > If the lights work from the house battery, then the problem is at the
> converter. If I were you, I would completely remove the old converter and
> put in new (at least 10awg) wires from the 9245 to both that fuse panel and
> a known good ground. 10 is actually OK as the 45 amp max won't be there
> that long, but more copper is always better.
> >
> > It sounds like something that should not be is powering the cab HVAC
> fan. I can't begin to tell you where to look.
> >
> > I have to go, I'll look in later and see if anybody has filled in.
> >
> > Matt
> > --
> > Matt & Mary Colie
> > '73 Glacier 23 Chaumière (say show-me-air) Just about as stock as you
> will find
> > SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
 
Mac is not quoted again.

Mac,

Yes, the stuff in the box is in front...

I have a very different coach, so I am working from shaky memories here, but I remember the circuit breaker, the boost solenoid and that junction to all be in the APU space.

That is just about all the help I can be tonight.

Good Luck

Matt

--
Matt & Mary Colie
'73 Glacier 23 Chaumière (say show-me-air) Just about as stock as you will find
SE Michigan - Twixt A2 and Detroit
 
Thanks Matt and Ken for the info.

I have printed your replies so that I can take them out
to the coach tomorrow and try to locate where I need to
put or move wiring.

Whew! My brain is getting fatigued trying to figure all
this stuff out. I'm a retired electronic technician but
have next to ZERO experience with vehicular systems!

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ex-Palm Beach, 76 ~ ~ ~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
_______________
*[ ]....[][ ][]\
*--OO---[]---O-*
 
I suggest that you simply your approach and tackle one symptom at a time.

It seems that everything on the engine side is OK except that the alternator voltage is a little high. The question I have is where are you measuring this high voltage at? If it is at the alternator then I can see how it could be this high under higher current loads. If it is at the center terminal on the isolator then it could be a little lower depending on how warm the alternator is.

Here is what I would do to verify your numbers.
1. Disconnect that combiner and get it out of the picture. It is not doing anything for you at this point.
2. Start the coach and measure the voltage at the center terminal of the isolator ground Use the aluminum plate that the isolator is mounted on for ground.
3. With the coach still running measure the voltage at the top and bottom terminals of the isolator. One of them is the house battery system and the other is the engine battery system.
4. with the coach still running measure the voltage across the the engine and house batteries.

I expect that the above measured voltages in steps 2 through 4 will be progressively lower due to various voltage drops in the system.

There is a sense line hooked to the alternator that will sense these drops and raise alternator voltage output to make up for these drops. That is probably what is going on here. After we get those above numbers we will be able to tell this for sure.

Enough of the engine side. Now let's look at the house side.

You said that the engine driven alternator will charge the house batteries and you should have verified that in step 3 above. This tells me that the circuit between the isolator in front to the batteries in back is intact. So now what we need to do is get the new converter working. You said the converter output is 14.? volts so we know it is functioning. It just needs to be hooked up to the correct location. Since the converter's primary job is to supply +12 volts to the house accessories, I suggest that you connect + output of the converter direct to the buss side of the fuse panel mounted in the rear power cabinet next to the converter. The minus output of the converter and the other ground lead from the converter should be connected directly to the body of the coach. There is a place behind the converter cabinet where you an attach these. Be sure to use a tooth washer and some anti-oxidation grease when you makr this connection.

That is it. Plug in the converter and take some voltage readings. You should something around 13.8 to 14 volts out of the converter, also at the fuse panel, and because the fuse panel is hooked to the house battery(s) you should also see 13.8 at the house battery(s).

After you have all of that working correctly you can go back and re-attach the combiner if you want. The only added function you will see with the combiner attached is a change in the voltage across the engine battery.

With the combiner attached, and the converter on, you should see 13.8 or so volts across both the engine and the house batteries. Without the combiner attached you will see 13.8 across the house battery and the real battery voltage of 12.6 to 12.8 across the engine battery.

That's about it. Please let us know how you do.

Ken B.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> > 1. Disconnect that combiner and get it out of the picture. It is not
> > doing anything for you at this point.
> >
> you could just turn it off
> gene

You are assuming it is not defective and wired correctly.

Disconnect it and get it out of the picture. It can be reinstalled, if desired, AFTER you get the other problems cleaned up.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
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