Coach battery charging

[ynkedad]

Info: I have a 91 Toyota Dolphin with a 92 camper on it and the house battery was bought in March of '09. Also For the last week the camper has been plugged in to an ac outlet so that I could check things out.

Anyway, I understand that the house battery is charged by the alternator, generator and an ac source. Also that the wall panel next to the sink will show me the battery condition. At least that's what I think I understand.

Here's my Issues/Questions:

1) When I push the button on the panel (by the sink) it only reads 2 bars for the house battery, whether the camper is plugged in or not and whether the truck is running or not.??

2) When I try and start the generator it won't start using the house battery or when plugged into an AC outlet, yet it will start when the truck is running. NOTE: The house battery itself shows over 13 volts when I use an ohm meter on it w/out it being hooked up to an ac source etc. Could this be a bad regulator?

3) When I'm hooked to ac power and or if the truck is running, I can't tell if the house battery is charging. Is there supposed to be a way to tell? Is it the wall panel?

4) When I run the generator, the little battery level guage on the panel infront of the sink is lit up and shows the house battery charging.

Is that panel infront of the sink supposed to show charging when hooked to ac power or when the truck is running? Or is it for the generator only?

I am truly sorry for being such a NEWBIE!!!

Thanks,

~Ray

[Maineah]

I don't think I would believe the charge lights on the panel they are not worth much. You should be able to check your charge rate at the coach battery with your volt meter the same way you would your truck charge rate right at the battery terminals. Your little DVM is your friend it will tell you what you need to know. The generator gauge will only show you the generator charge rate.

[ynkedad]

I don't think I would believe the charge lights on the panel they are not worth much. You should be able to check your charge rate at the coach battery with your volt meter the same way you would your truck charge rate right at the battery terminals. Your little DVM is your friend it will tell you what you need to know. The generator gauge will only show you the generator charge rate.

Thanks you!

Now I just need to figure out why the generator won't start off the house battery, but will when the truck is running.

[Maineah]

Do all your coach lights and stuff work not plugged in with the truck not running?

[Alvin]

I do believe the charge lights, since the battery does not have the capacity to start you vehicle n its own. Batteries can show 13 volts but the internal resistance can be high enough over time that they can't provide a serious amount of current for things like staring a truck. Solid state LEDs don't usually burn out,

Okay here is what I suspect. You have a bad or old battery.

See if you can charge it on a standard known good battery charger.... To a point that your vehicle starts. Give if a few hours to charge. If not, replace your battery and your troubles should be over.

I believe that you'll find that things work after you replace the battery. Most of my experience is with with lithium cells as an engineer... but along the way reading multiple data sheets, I know now that lead acid cells can deplete due to chemistry. I suppose that if you cared (or I cared) we'd test the chemistry. (test PH when you buy!... not that I do... oooo batteries are annoying, but don't cost that much really in the scheme of things..............I don't test. Never have...... never will ). Also, they can go bad from freezing, from multiple discharges... from plating... they are sensitive. Simply, if you can charge it with a known good standard run of the mill in your garage charger... it's fine. Otherwise, replace it.

[Gulfstream Greg]

As Maineah says, you need a volt meter. You need to check voltages at the battery when the engine is running, when plugged into shore power and when the engine is not running and not plugged into shore power. A volt meter will tell you what is or whats not doing what. You may have a bad battery that will not accept a charge. You may have a bad charger within the converter. You may have a bad isolator. You may have a combination of all of the above. Again, as Maineah says, you need a volt meter. They are cheap, very cheap. Consider a voltmeter an essential tool like the lug wrench to change your tire when its flat.

As a note: If a battery is bad it can show a normal voltage (12.6 volts is fully charged). Lead acid batteries do whats called sulfation when they are left in a discharged state for a long period of time. Sulfation is a build up on the plates. Short description is that your battery is toast at that stage. The panel in your RV is just a reference reading. It just reads voltage, not capacity.

You mentioned that the generator will start only when the engine is running. If you have the original 6300 converter the house (coach) battery is switched out of the circuit when plugged into shore power. When the truck is running the alternator is supplying power to the coach circuit through the isolator and gives the generator enough power (amps) to start. Your description points to a bad coach battery. Back to the volt meter. Volt readings (You need to check voltages at the battery when the engine is running, when plugged into shore power and when the engine is not running and not plugged into shore power) will really help in diagnosing the health of the system.

[ynkedad]

Do all your coach lights and stuff work not plugged in with the truck not running?

Yes they do.

[ynkedad]

As Maineah says, you need a volt meter. You need to check voltages at the battery when the engine is running, when plugged into shore power and when the engine is not running and not plugged into shore power. A volt meter will tell you what is or whats not doing what. You may have a bad battery that will not accept a charge. You may have a bad charger within the converter. You may have a bad isolator. You may have a combination of all of the above. Again, as Maineah says, you need a volt meter. They are cheap, very cheap. Consider a voltmeter an essential tool like the lug wrench to change your tire when its flat.

As a note: If a battery is bad it can show a normal voltage (12.6 volts is fully charged). Lead acid batteries do whats called sulfation when they are left in a discharged state for a long period of time. Sulfation is a build up on the plates. Short description is that your battery is toast at that stage. The panel in your RV is just a reference reading. It just reads voltage, not capacity.

You mentioned that the generator will start only when the engine is running. If you have the original 6300 converter the house (coach) battery is switched out of the circuit when plugged into shore power. When the truck is running the alternator is supplying power to the coach circuit through the isolator and gives the generator enough power (amps) to start. Your description points to a bad coach battery. Back to the volt meter. Volt readings (You need to check voltages at the battery when the engine is running, when plugged into shore power and when the engine is not running and not plugged into shore power) will really help in diagnosing the health of the system.

Yeah, I was going to test things yesterday but got sidetracked. So i'll be doing this today and i'll report back.

Thanks guys for your replies, they're much appreciated!

[Maineah]

Yes they do.

What happens to the lights if you try to start the generator?

[ynkedad]

Okay, I tested the battery by itself (after sitting overnight).

The battery read in the 8v range on its own, But the volts steadily climbed (indicating charging) when plugged in or when the truck is running w/out being plugged in. So it looks like we found the issue...the house Battery!

Btw, my rv has the 6300-A converter with the coach battery charging option.

And for whatever reason my panel by the sink works just fine now!

Thanks again for the help fellas!

Edited November 11, 2010 by ynkedad

[Alvin]

Okay, I tested the battery by itself (after sitting overnight).

The battery read in the 8v range on its own, But the volts steadily climbed (indicating charging) when plugged in or when the truck is running w/out being plugged in. So it looks like we found the issue...the house Battery!

Btw, my rv has the 6300-A converter with the coach battery charging option.

And for whatever reason my panel by the sink works just fine now!

Thanks again for the help fellas!

I'm glad you found the issue. Like I mentioned in my earlier post, I've seen this many times in various vehicles... nobody likes to pop for a new battery, but they're the darndest things... they will deplete and go bad at different rates... they are subjected to varying seasons. As I said, I never waste much time with a battery, and they simply don't cost that much to replace... and it almost always boils down to chemistry depletion. If you have one that is weak, you charge it, and it's still weak, just skip to the "bite the bullet" part and buy a new one.... almost.

There is one test I like to do, and that is that I connect my current meter in series with the battery and the key shut off (of course) and measure to see if anything is drawing current... there will be a few uA's maybe if you can measure that for your clock radio... but it should be next to nothing. This test does nothing but test to see if the vehicle is drawing power for some strange reason that you didn't know about. If you want, you can turn on your headlights after you've connected your FUSED meter (on the right setting!) and test to make sure your tester actually works... which should draw an amp or two when the lights are on.

[Gulfstream Greg]

One thing about the 6300 converter (in case it has not been mentioned) it uses a relay to switch the battery in and out of line. When you plug into shore power you will hear a clunk. That's the relay. When unplugged the relay connects the battery to your coaches 12 volt circuitry. When plugged in the relay disconnects the battery from the 12 volt circuits and connects the battery charger to the battery. Power to the interior circuits is provided by the 6300 and not the battery when plugged into shore power. That relay is not in any type of case and prone to getting a ton of dust layered on it and on its contacts. Also when the 6300 is supplying power to the 12 volt circuits it is not pure DC as with the battery. Its a half wave rectified power supply and there is allot of AC voltage also being feed into the circuit. Very bad for anything that needs 12 VDC directly. And the battery chargers in the 6300 do go bad. They also tend to overcharge batteries if left connected for too long. Just remember when your plugged into shore power that the battery is disconnected from the interior 12 volt circuit and that includes your panel readout.

[picklebill]

Info: I have a 91 Toyota Dolphin with a 92 camper on it and the house battery was bought in March of '09. Also For the last week the camper has been plugged in to an ac outlet so that I could check things out.

Anyway, I understand that the house battery is charged by the alternator, generator and an ac source. Also that the wall panel next to the sink will show me the battery condition. At least that's what I think I understand.

Here's my Issues/Questions:

1) When I push the button on the panel (by the sink) it only reads 2 bars for the house battery, whether the camper is plugged in or not and whether the truck is running or not.??

2) When I try and start the generator it won't start using the house battery or when plugged into an AC outlet, yet it will start when the truck is running. NOTE: The house battery itself shows over 13 volts when I use an ohm meter on it w/out it being hooked up to an ac source etc. Could this be a bad regulator?

3) When I'm hooked to ac power and or if the truck is running, I can't tell if the house battery is charging. Is there supposed to be a way to tell? Is it the wall panel?

4) When I run the generator, the little battery level guage on the panel infront of the sink is lit up and shows the house battery charging.

Is that panel infront of the sink supposed to show charging when hooked to ac power or when the truck is running? Or is it for the generator only?

I am truly sorry for being such a NEWBIE!!!

Thanks,

~Ray

Greg and mainea are right- a voltmeter is a real useful tool for the money. I have also found that a battery load tester is very useful as well, but not as cheap. I use a Harbor Freight Tools carbon pile load tester because it will put a 500 amp load on the battery while monitoring the battery voltage. An infallible test. I think I paid about 60 bucks for it. You can also find the cheap ones (less than $25), but they are way too wimpy.

Bill

[Lee & Joan]

I have a question regarding how the generator is wired into the power converter. I just got this Sunrader and although the generator engine ran, no electric power was produced. It is the Kohler 2.5 KW. I found that the 8 gauge green ground wire from the generator and the ground leg of the house wire it was connected to were both burned. I replaced these and now have power. The house wire does not go over and connect to the power converter like I thought it should. Instead it heads under the closet where I think the land line goes outside the body. It obviously was not wired properly to melt the ground. I will have to tear into the closet to find where it goes. When I look in the 92 Winnebago wiring diagram I see the generator output being plugged into the landline cord, thus you could not plug into land power while the generator is running. But my Sunrader does not have a generator outlet socket. Where do I run the power from the generator? Into the power converter? Parallel it to the land line power cord?

[Maineah]

If there is no 30 socket there is a transfer switch of some nature and it is automatic exactly where it is on yours I can't tell you but you have one. Generally the converter wiring goes to the main breaker on the input side. I would be a bit curious about any burned wiring particularly the green one the MH's have a floating neutral meaning it is not connected to the ground as most houses are the reason being protection from bad campground wiring. If the ground and neutral were tied together and the wiring was reversed on the campground outlet you would end up with a hot MH frame not a good thing. I have a cheap little tester that plugs into an outlet and I all ways test campground wiring lot of DIY's out there. Have a good look inside of you breaker panel all the white wires should go to a insulated buss bar with no ground wires (green or other wise) and the blacks to the breakers. The breaker panel frame work should be connected to a ground wire going to the frame. It takes a lot of current to burn a #8 wire it will handle 50+ amps far more then the #10 power cord and 30 amp main or the generators 20 amp will handle. A bad connection at a terminal will some times burn the wire at the connection but not very far from that point. Check your white wire with an ohm meter and make sure there is no continuity to ground if there is it needs to be fixed turn off the main breaker first you may get a false positive from the converter windings.

[Lee & Joan]

Thanks Maineah, What I have at the generator are 4 black wires coming from the generator head, two go to a capacitor and two are the power out. The power out wires one goes to the frame ground and from that ground comes the white “LO” wire. The other black goes to a breaker and becomes the black “LI” hot wire. A third wire grounds to the same as the White and becomes the green “Hazard ground” wire. This conforms to the wiring diagram in the Kohler manual. I see what you mean about reversed campground supply making the frame hot, perhaps this is what happened. The previous owner included a two prong “adapter” with no ground and maybe the use of that in a miswired campground fried the wire. It is interesting that only the green and not the white 8 gauge melted, and yes that would take a lot of current.

I will now tear into the breaker box area under the closet, this is the area where the landline comes in, and the generator wire goes. I will see what I find there and report back. Thanks for your help, Lee

[Lee & Joan]

OK, when I took the bottom out of the closet I found where the wiring all comes together. The land line and the generator line both go into a transfer box and the transfer box then sends the 115 VAC to the main 30 A breaker which then feeds two other AC breakers. When I have the landline plugged into a properly wired AC source the transfer box clicks, the battery charger starts and AC power is at the three AC outlets. I did find that the AC outlets are reverse wired IE the narrow "hot" slot is neutral while the wider neutral slot is hot, but ground remains ground.

Then I went over from the transfer switch to the generator line and found that the transfer switch was keeping power from feeding back that line, although I did get about 0.3 volts between neutral and ground, but nothing between hot and neutral. So this means that the transfer switch is shutting off the generator line when plugged into landline power. I did find that the ground wire from the transfer switch into the breaker box had gotten hot enough to slightly bubble, so this problem effected the ground wire all the way from the generator to the transfer box to the breaker. God, don't you just hate wiring problems. There is really a lot going on between those two boxes and all the associated wire coming to and fro.

Also, you were right Maineah, the white neutrals are running to a buss bar isolated from ground in the converter box and in the transfer box, and the grounds are grounded to the frame. Actually the whites & blacks both appear to be switched in the transfer box. This is not the case back at the generator however. The Kohler diagram shows both white and green grounded and thats the way they were wired.

Any advice you can give will be appreciated. Thanks, Lee

Edited December 17, 2010 by Lee & Joan

[Alvin]

Applying generator power is also just a hair tricky upon starting and turning off the generator since the voltage can fluctuate. To get past this, a generator transfer switch typically has a time delay circuit built in to allow generator AC voltage to stabilize. I don't know if you have this type or not, but if you notice a delay when you turn on the generator in the transfer relay clicking over to generator, then you probably have this type of transfer box. If you don't have this type of transfer box (I had no transfer box initially in my rig), then the best procedure is to manually turn off all breakers prior to starting your generator, start the generator, wait several seconds, then turn your breakers on. Follow the reverse procedure when turning off the generator.

If you need a transfer switch with a built in time delay, this is the type I bought and it works great:

http://www.progressivedyn.com/prod_details/trans_relays/pd5110610.html

It sounds like you've got the reverse wiring issue covered, I just wanted to make sure someone mentioned the variance in the voltage when starting/stopping your generator... avoids possible fried appliances.

[Lee & Joan]

Thanks Alvin, I will check that out tomorrow after I replace the bubbled wire. I can plug the voltmeter into an AC outlet, crank over the generator and see if it feeds low voltage or waits for the full 115. Good tip.

[Maineah]

To me the safest/simplest is the socket/plug arrangement. Your transfer switch is most likely a double pole single throw relay with the land side normally open once you plug it in it energies the relay coil and connects the mains and disconnects the generator simple but effective. As far as the generator grounds that's OK. Good find on your sockets don't you have a GFI some where in the system? If you don't I would think about adding one you can use one GFI to protect all the other outlets. The transfer switch does two things protects the generator from reverse current and disconnects your power cord so you don't end up with charged prongs or back feeding the grid.

[Alvin]

As the generator starts and stops, it is not simply the voltage which can do in your solid state devices, but it is also that the generator engine is coming up to speed and is not yet 'governed' to produce a 60-Hz output. Almost all solid state devices and appliances are supposed to work at 120VAC/60Hz. This 60Hz is not at all 60Hz until the generator has reached it's running set point and is regulating the alternating current (voltage) to occur at approximately 60 Hz (or 50 Hz in many non-USA countries). Chances are a given device can make it through this period, but the nature of the startup/shutdown ramp on a generator output is quite literally a complex time-varying function of voltage and phase.

There are some generators which will not allow this voltage to be applied until something close to 120VAC/60Hz is reached... which is nice. Yours may or may not be at issue, but you can probably find out by doing a little research, perhaps finding a PDF of the operator's manual or a call to a generous but knowledgable generator-manufacture representative may work too. Unless you know your generator is designed to work this way, I can tell you that almost all simple voltmeters will only give you a part of the story... and it's even worse than that (as good students of electrical engineering can tell you), because most voltmeters have AC settings which are ONLY designed to read accurately at 60Hz frequencies, and are therefore not suitable for reading startup/shutdown voltage and phase information. For doing this, you need any cheap oscilloscope, triggered at the moment you press the start button and the spark-plug starts firing. Such a scope can give you an accurate picture of the rapidly time-changing startup ramp, along with any unknown transients and you can also get a good picture of 0 to 60Hz frequency variation (and possible overshoot) if you set the recording for the proper scale.

This is why so many RV's simply use the simple "time-delayed" generator transfer switch... more expensive monitoring equipment could also give you active feedback which could also determine when it is safe to switch in the power, but at a cost of several hundred dollars. (I paid about $80 for my time-delayed switch).

I hope I'm not coming across as some kind of wanna-be know it all. I'm just an electrical engineer who has been exposed to my profession for about 25 years, and I hope this helps.

I agree with Manieah too about his solution with the plug...it works; I especially agree with him about the GFI plugs (I think you can have 1 of these for every 3 or 4 outlets). The cost of the box, plug etc. is minimal, about $25 probably, and you can get a GFI for $13 bucks... do this regardless of which method you use! But the cable-n-plug method is not automatic and it still leaves open the possibility that your RV can be plugged in, with the breakers on, and THEN you or someone in your RV pushes the start button on the generator... causing 2 to 4 seconds of electrical chaos throughout the entire system.

One final admission. I had my step-son work on my generator (he is a mechanic) to get the gas line and all hooked up. It worked great... for one try. Then, he did exactly what I just outlined in the above paragraph... started the generator with the RV plugged in... to devices. The damage was too my generator itself, and cost me several days of research and $110 for a new generator voltage regulator to fix the problem.

Therefore, I still recommend the transfer switch for those (like me!) who make mistakes.

[Maineah]

That is why I like the power cord plug in for the generator it is impossible to screw up you have to unplug from the land power and then plug into the generator output. All portable 60 cycle generators either turn 1800 or 3600 rpm to produce 60 cycles (exception being an inverter generator) the best way to adjust a generator is with a frequency meter, set the engine speed to 60 cycles the rest will follow. The Onan generators are by far the best because they will not output until all is well.

[Lee & Joan]

Hey There Alvin & Maineah,

Thanks for the great advice, It is always good to learn something new although I probably won’t be getting an oscilloscope anytime soon. But I will leave the main breaker OFF for a few minutes. I spent today replacing the wires from the generator to the transfer switch and from there to the main breaker. I just gave it a little test and I am getting 120 with proper polarity at the outlets plus charging the battery with the generator running.

Wha ~ Who. Then I stopped the generator and plugged in the landline and got reversed polarity on the 120 AC even though all the wires are black to black and white to white, must be something wired wrong in the power cord.

So next I pulled out the heater and as I am loosening the gas line the wrench slipped and I took off the top half of my thumbnail, just pealed it back. I just taped it back down, and I think I better crazyglue over the top of that. I think I have had enough fun for today… Lee

[Maineah]

Ain't it fun working on old MHs! Is the end molded or does it have a cord cap? If some one put a cord cap on it I would have a look there if they drove off while it was still plugged in it may have wrecked the plug. With the plug facing you and the round pin up round pin green left blade white the right blade black.

[Lee & Joan]

Score another Bingo for Maineah !

Took the cover off the cord end

Looking at the plug spade (male) side

not the back connection side where the screws are

with the round ground up

I see Green top round

Black lower left spade, White lower right side spade

Will switch the two

Thank you Maineah!!!

[Vanman]

<br />One thing about the 6300 converter (in case it has not been mentioned) it uses a relay to switch the battery in and out of line. When you plug into shore power you will hear a clunk. That's the relay. When unplugged the relay connects the battery to your coaches 12 volt circuitry. When plugged in the relay disconnects the battery from the 12 volt circuits and connects the battery charger to the battery. Power to the interior circuits is provided by the 6300 and not the battery when plugged into shore power. That relay is not in any type of case and prone to getting a ton of dust layered on it and on its contacts. Also when the 6300 is supplying power to the 12 volt circuits it is not pure DC as with the battery. Its a half wave rectified power supply and there is allot of AC voltage also being feed into the circuit. Very bad for anything that needs 12 VDC directly. And the battery chargers in the 6300 do go bad. They also tend to overcharge batteries if left connected for too long. Just remember when your plugged into shore power that the battery is disconnected from the interior 12 volt circuit and that includes your panel readout.<br />

<br /><br /><br />

I was getting 14.0 VDC on the fully charged coach battery when plugged into home 110 or on the generator. I rotated the trimpot on the ckt board 20 degrees CCW and now have 12.91VDC. Thought this was ok till I used the old manual battery charger I've had forever, (Schumacher model 60-PE) which has 4 modes; 50A,10A,Trickel, and Maintain. Maintain keeps it @ 12.60 V and Trickel holds @ 12.98 VDC. So my question is what should it be set to??? I would think less than trickel??, but all the way down to 12.60?? What are you running at?? John