Does the generator charge the batteries?

[bestbowl]

I was wondering if the generator charges the car battery and/or the auxiliary battery in a 1994 Winnebego/Toyota Warrior or if only the engine alternator does the job?

Thank you

[Maineah]

Yes it does charge the coach battery but it does not charge the truck battery. Even a portable one will charge the coach battery if the coach power cord is plugged into it. If you have a weak truck battery and a relay type isolator you can charge the truck battery too if you turn the key on, if it's a solid state type that won't work you'll still have a weak battery.

[waiter]

With the Genset running (or plugged into shore power), your supplying 110 Volts AC to the coach and the 12 volt "Converter" (Fancy name for 12 volt power supply/battery charger)

As Maineah said, this will charge the Coach, but not the truck.

You could turn the truck ignition to ON, if the truck battery has enough power to pull in the Isolator, then this will charge the truck battery also (very slowly)

I'm not sure what "Converter" you have, but the early model cheap Converters do little more than supply a trickle charge to the battery, They'll charge it up, but it will be hours.

The newer model Converters (I upgraded mine) can supply plenty of amps to the 12 volt circuit, plus deliver those amps at a voltage that's high enough to charge the battery. They also have the intelligence to switch modes so when it detects the battery is charged, it will reduce the voltage and go into a "Trickle" mode so it won't cook the battery. This is a problem with the original Converters, they'll cook the battery if left plugged in for extensive periods of time (weeks/months).

Converter Upgrade

John Mc

88 Dolphin 4 Auto

[Maineah]

His being a 94 most likely has at least a decent converter/charger but the only way would be to have a look at it and see if it's a switching power supply. If it has a big ugly transformer and very few solid state parts Waite's right it's not a real good charger.

[bestbowl]

Hi,

Thanks for all the info. Been running the crappy little aluminum/silverish stick one. Doesn't seem to charge either battery although I tested it and it is putting out a charge. Haven't tested actual amperage- just power with a cheapy power indicator light.

I just bought this one although I am sure it is overkill. I am hoping it will charge both... What do you think?

http://www.boaterbarn.com/promariner_proisocharge_12v_battery_isolator_79394_prd1.htm

[waiter]

Been running the crappy little aluminum/silverish stick one. Doesn't seem to charge either battery although I tested it and it is putting out a charge. Haven't tested actual amperage- just power with a cheapy power indicator light.

I'm not sure why you bought an Isolator.

The Isolator you mentioned will charge either way, If the coach is plugged into shore power, or, your generator is running, This isolator MAY charge your truck battery also (Depends on the converter)

BUT - Only if you have one of the newer style Converters.

The Converter takes 110Volts ac and converts it to 12 volts.

If you have the cheap OEM Converter, it puts out a fixed voltage, about 13.6 volts (you can adjust this). They can provide about 30 to 35 amps, but the voltage does drop as the amps goes up.

The problem with these converters, they don't have any intelligence built in to change voltage. If you set them to high (most are) they'll overcharge and boil your battery. if they are set to low, they will not charge the battery. The problem is, there isn't a "just right" setting. The voltage must be changed to accommodate the battery charge.

IMPORTANT NOTE - The original Converters are designed to provide enough current (amps) to power coach devices (Lights, furnace blower, etc) while on Shore power.,

They are NOT designed to charge a battery, (The voltage is adjusted to low). Althougfh they will charge a battery, the voltage is set as a compromise between cooking the battery and not charging it at all.

Thats the difference between the older original converters and the new style intelegent converters, The newer Intelligent Converters (I upgraded mine) actually change voltage to provide optimal charging voltage to the battery.

My Thoughts on the Isolator:

I believe the original Solenoid type Isolator is OK for what we want to do. "Keep from killing the Truck battery when we leave the furnace blower run for 3 straight days and have completely discharge the Coach battery (Hence Deep Cycle)

If theres a reason to run the Truck off the coach battery (i.e. I killed the truck battery because I forgot to turn off the headlights). A simple jumper wire on the Isolator will energize the Isolator, and may provide enough power to get the truck started, OR, charge the truck battery via the Converter (depends on wire size, probably #10, and what converter you have).

John Mc

88 Dolphin 4 Auto

[bestbowl]

Thanks for all the info John. I bought the isolator because I kept killing both batteries because the generator was never fully charging them even if I ran it for 8 hours. I just figured it may be a bum isolator. The coach battery was dying by charging electric bicycle batteries while driving. And the truck battery was being quickly killed by running a high wattage stereo system while the truck was not running. I also installed a 180 amp alternator in hopes that it would charge quicker and to a higher capacity especially because there is a 2000 watt stereo system installed and I regularly charge electric bicycle batteries that pull 500 watts for 4 to 8 hours (although I only do this while driving 40+mph). So I figured if I have a 180 amp alternator I should have a 180 amp isolator...?

I figured that the isolator was not functioning properly because the batteries actually never charged completely even under normal use (even pre stereo/bike batteries and either under alternator or generator power). How do I know if I need to replace the converter and if the converter is even functioning properly? The plate says it's a 32 amp series 6300 A model 6332.

Thanks again.

[Maineah]

What that isolator is, is a "smart" isolator it senses battery voltage and leans towards the "weaker" battery for the charging cycle it's better then a normal solid state isolater and it sounds like transistors instead of diodes ie. switches. It's pretty pricey but it looks like it will sink the power you need. As far as your converter is concerned the 32 amps is most likely it entire output most of it going to the 12 volt loads and like Waiter said they don't have much charger output. One of the very best up grades you can do is a really good converter/charger most not only do a very good job charging they also load share so when the demand it high for a recharge they drop back the 12 volt current output and weight it towards charging the battery. Most of the time you don't really need a lot of current to run lights and such.

[waiter]

Your generator supplies 110 Volts (just like shore power) It doesn't recharge your coach battery directly. The generator supplies power to your Converter. The Converter you have is not designed to charge your battery, (It does a little bit, as I described in my previous post)

If you want to deliver a lot of charging amps to your battery from your generator, you'll need to upgrade your converter. (I have a 55 amp version)

As for the Alternator.

As I mentioned in another thread, if your going to pull amps from the Alternator and go all the way back to your coach battery, you'll need to do some serious upgrading to the wiring, fuses, circuit breakers. The #10 wire is not acceptable for high current loads that your bike battery chargers are demanding. I recommend at least a #4 wire.

Doing a calculation, using 25 ft of #10 wire. If your Alternator is putting out 14.6 volts (good strong charge voltage) and your drawing 100 amps, If you measure the voltage at the end of that #10 wire, it will read 12.1 volts. You won't charge anything with that (Yes, the #10 wire is dropping about 2.5 volts)

If you ran #4 wire, the voltage drop is about 0.6 volts, you would get 14.0 volts, It would charge, but not to full capacity.

A #2 wire would be much better, it only drops 0.4 volts.

If this entire exercise of needing all these amps is to charge those bike batteries with an inverter, I would simply wire the inverter directly to your truck alternator/battery through its own isolator. I believe it would be simnpler and the least expensive.

JOhn Mc

88 Dolphin 4 Auto

[bestbowl]

Sounds good. Will do. Can you recommend a good converter that will fit into the same spot as the original? Also do you think 55 amps is okay for my application or should I go 60 or more?

[waiter]

I was thinking about this last night, I don't have a generator so I can't verify this:

If your running your generator while driving down the road, Does the Converter charge the Coach battery or does the truck charge the coach battery???

I'm thinking that the Converter does!

If your trying to charge the Bike batteries through an Inverter, I would wire that inverter to the truck circuit with its own isolator. If you wire it to the Coach circuit, you need to upgrade the entire Coach 12 volt circuit to support the 100 plus amps.

HOWEVER - If your Bike Charger can run off 110 volts AC, Why not run it directly off the Genset and don't mess with an inverter.

Regardless, I would recommend doing the Converter upgrade.

Here's a link to the forum I wrote up when I did mine:

Converter Upgrade

Here's a link to the Best Converter web site page that talks about their upgrade:

Best Converter Web Site

John Mc

88 Dolphin 4 Auto

[bestbowl]

Hi John,

I don't run the generator while driving. I run the 750 power inverter connected via 4 gauge wire directly to the truck battery while driving. I think the main problem is that I run the stereo which is also connected to the truck battery with the engine off. Sometimes I run the generator while I am playing the stereo and the truck is off but it doesn't seem to charge the truck battery at all.

And when I get home I plug in the A/C power cord and it doesn't charge the batteries fully either.

EIther way both the truck and the coach battery are never fully charging although they are both new and in good condition. The only way to charge them completely is directly with an external battery charger plugged in at home. The truck battery will charge after an hour or so of driving on the freeway if it's fully drained. But the coach battery never fully charges either via generator, alternator or A/C power cord and the generator doesn't keep the truck battery charged with the stereo running while the truck is off.

[waiter]

1) - sounds good on the bike batteries, make sure you have a heavy wire (#4) from your 160 amp Alternator to your truck battery. Be careful of deep cycling your truck battery, it can destroy a new battery.

You have a 160 amp alternator, and it doesn't charge the truck battery, then you have something wrong with the truck alternator/battery circuit. (If you've deep cycled the truck battery several times, it may no longer hold a charge)

2) - Remember, your Genset does NOT recharge your coach battery directly, it supplies 110 to the converter and the converter charges the coach battery.

ALSO - Your Converter does not charge the truck battery, this is the purpose of the isolator, to isolate the Truck battery from the Coach battery when the truck is not running.

HOWEVER - The Isolator that you were looking at has intelligence built in so it "MIGHT" allow this to happen. IMHO - keep the standard isolator, and just don't run stuff off the truck battery when the truck isn't running.

3) - If this is a stereo that you want to run when the truck is not running, you might consider rewiring it so it runs off the coach battery instead of the truck battery.

4) - you have the old style converter. If your deep cycling your coach battery, the converter will have a rough time recharging it - Upgrade your converter.

5) - Get a digital voltmeter and measure the voltages on both batteries;

a) No loads, no shore power, no genset power, truck not running

No loads plugged into shore power (no genset, no truck)

c) No loads genset running (no shore, no truck)

d) No loads Truck running (no genset, no shore)

Post these readings and lets see whats happening.

John Mc

88 Dolphin 4 Auto

[Maineah]

I don't know if the isolator you bought is a combiner you might call them and ask, a combiner will charge both batteries but again if you are trying to charge them with a old charger it's not going to happen with the batteries you have and the discharge rate it will never keep up even with the generator running. If you upgrade you may want a 60 amp or more charger but be sure you have a generator to match. If you don't go very far with the camper the alternator may not fully charge your truck battery either it takes a pretty good drive to charge a weak battery. The amp rating is total amps not just charge amps so if you are consuming a lot of current the charge rate suffers ie. 40 amps of amplifer draw and a 45 amp charger/ converter your battery is going to lose out.

[bestbowl]

Sounds good. I will post the results.

I am using #4 wire directly from the truck battery to the 750 power inverter/bike batteries. Is it okay to be wired to the truck battery and not directly to the alternator? And it's a 180 amp alternator not a 160. If I rewire the stereo to the coach battery I am afraid that the alternator will not charge it fast enough. It's a 2000 watt constant draw and it's always on while the truck is running (and not running as well ;-)

Do you think that it would be okay even at 2000 watts? It seems that the alternator charges the coach battery very slowly. I have not yet changed the isolator so maybe this will change...

I was considering putting the stereo system on a switch so that I can switch between the truck battery while running and the coach battery while not. That way it will basically run from the generator while the truck is off...?

It seems either way I need to upgrade the converter as well.

P.S. by "deep cycling" are you referring to charging the batteries with an external battery charger?

[waiter]

2000 Watts - I think you need to invest in a pair of earphones.

Electronics 101

P=IE P (watts) = I (amps) x E (Volts)

or

I = P/E

P = 2000

E = 14.0

146 amps = 2000/14

Your stereo amplifier should also be tied directly to the Battery with a #2 cable.

You should also have a #2 cable between your Alternator and the battery.

I believe your going to find that you do not have enough capacity (180 amps) to charge the Truck and Coach batteries, AND run your Stereo, AND charge your Bike Batteries. (Add up all the numbers and your over capacity)

ALSO - the converter upgrade I use is only 55 amps, it will not supply enough amps to run the stereo.

Rather than charge the Bike batteries with an inverter, Why don't you just plug the Bike Battery Charger into you generator and run the Genset to charge the bike batteries.

FYI 1 hp = 746 watts

NOTE - Let me know when you go camping, because I don't want to be in the same county with your 2000 watt stereo

John Mc

88 Dolphin 4 Auto

[bestbowl]

NOTE - Let me know when you go camping, because I don't want to be in the same county with your 2000 watt stereo

I HATE earphones.

The stereo is used to DJ at music festivals and for driving.

I usually don't crank the full two grand in the woods.

I may upgrade the #4 to #2 if they have #2 in welding wire which I am not sure that they do. The amps have zero issues running full power with the #4 other than the draining the battery when the truck is off. Which I am pretty sure that that rewire wouldn't remedy...?

I use the inverter becasue I have a honda gen that I can only run while stationary. I use the bikes constantly and they mostly need to be charged between runs.

The alternator is connected via the factory wiring harness. Are you suggesting I rewire it? I am not a huge fan of messing with mid-90s Japanese computer controlled wiring harnesses. On my '67 Camaro I would be more apt to bypass electrical stuff, but on this....

P.S. One more interesting point. Why is the factory wiring to the coach battery 10 gauge to the positive and #2 to the negative? Shouldn't be reversed if not both #2 or #4? 10 gauge is ridiculous for the coach...

Readings done with a voltmeter that doesn't read decimal. It seems to be mostly an A/C voltmeter.

a) No loads, no shore power, no genset power, truck not running Truck 12 Coach 12

No loads plugged into shore power (no genset, no truck) 12/13

c) No loads genset running (no shore, no truck) 12/13

d) No loads Truck running (no genset, no shore) 14/13

[bestbowl]

Hi Maineah,

I am going to get the converter next week. I just dropped $160.00 on the damn isolator (which I think with the 180 amp alternator upgrade and the battery issue was a good investment), $200.00 on the alternator and $800.00 on the generator.

I have the Honda 2000i generator. Do you think that the 55 amp converter is sufficient or do you recommend a 60 or 70? I just don't want to go big if its unnecessary especially after blowing a chuck of change on the isolator. At the same time it would be moronic of me to buy the 55 if I could really use a 60 or 70 for a couple bucks more.

Thanks

[waiter]

OK on the portable Generator, I thought you had a built in Genset, thats why it wasn't making sense to me to use an inverter!!.

We need a little more accuracy on the voltage readings, 12.0 volts on a battery is partially discharged, (about 1/3 of its charge) Minimum should be around 13.2

13.8 - 14.2 for a battery that's being charged at a moderate rate

above 14.2 i.e 14.6 - 14.8 for a battery that's being charged heavily)

Generally, your readings look low, but its hard to tell without the decimal point. need XX.X accuracy.

Amplifier Wire size / Truck Battery

You amplifiers probably aren't sensitive to a 1 or two volt voltage drop, so your probably OK with the existing #4 for the amps.

If your going to run this off the truck battery, you probably need to consider using deep cycle battery for your truck starter battery. Standard starter batteries are designer for short duration high current draws (starting) and generally don't recover when deep cycled.

Converter size

Although a 70 amp converter would be a WAY OVERKILL on a standard Toyhouse, its only 1/2 of what you need to run the stereo (2000 watts needs 142 amps)

However, if your not cranking up the volume, it should be OK.

Alternator Cable

If the factory cable is a #10 between the Alternator and the battery, And I assume it probably 10 ft long, that cable will loose almost 2.0 volts at 180 amps.

What that means - Your Alternator could be pumping out full amps at 14.6 volts thinking its doing a great job charging the battery, but when you measure the voltage at the battery, its only 12.6 volts, the battery will not charge (not enough to even trickle charge).

You need to trace the wire from the Alternator to the battery, and ensure its one solid piece, If so, I would just add a #8 or #6 wire to it (you would have two wires from the Alt to the Bat, the original #10 and a #6)

NOTE - Before you add a wire, read this. Many alternators have whats called a "Remote Sense". Its an extra wire (small probably #18 or 20) that comes out of the alternator that attaches directly to the battery. The Remote Sense is basically a "Voltmeter" that reads the voltage at the battery, the alternator then adjusts its output voltage to make sure the correct voltage is at the battery, this automatically accommodates for wire resistance loss (described below). If your alternator has this "Remote Sense" , make sure it goes to the battery and isn't just jumpered to the Alternators "BATT" terminal.

IMPORTANT - If you have the remote sense hooked up correctly (goes to battery), DO NOT connect your inverter or stereo directly to the alternator. The voltage at the alternator will be higher and could damage your equipment.

Depending on where you attached your wires for the stereo and the inverter (I assume you attached them at the battery terminal, and not the alternator terminal) If so, all the amps that power the stereo and the inverter must flow through that #10 wire that runs between the Alternator and the Battery.

#10 wire to coach battery

Keep in mind, the intent of that wire is to supply 15 - 25 amps (I think its fused at 35 amps) to run coach appliances and recharge the coach battery when the truck is running. A 10 amp draw for a wire 25 ft long will drop the voltage less than 1/4 volt. (You'll see this when you take readings with your accurate voltmeter)

#2 to Negative

Not sure why they did that. For a standard Toyhouse, a #10 from coach battery minus to chassis would have been more than acceptable.

John Mc

88 Dolphin 4 Auto

[bestbowl]

WIll this converter work?

http://cgi.ebay.com/ebaymotors/POWERMAX-100-amp-RV-Power-Converter-Battery-Charger-/180728473105?pt=Motors_RV_Trailer_Camper_Parts_Accessories&hash=item2a1441a611#ht_1454wt_673

I will have to buy a new voltmeter on Monday and I will post the readings.

It's hard to see the actual size of the factory alt wire as it's enclosed in a protective plastic sheath. If it's alone in there it looks to be either #6 or #8 wire. There is a separate harness with 3 #18 or so wires-yellow with a red stripe, red and white (which may or may not be your "remote sense" wiring). So with this combo I don't know if it clarifies if the charging wire is alone in the sheath or wrapped up with the remote sense making the positive only #10. I may have to just tear into it and see...

As far as the coach #10 positive; do you think I should bypass it and run #4?

With the factory circuitry, panel, etc., would this even make a difference or would I need to upgrade everything to make the #10 to #4 positive wiring upgrade worth while/make any difference?

[waiter]

If you have the Stereo and Bike charger on the Truck, There is no need to upgrade the coach wires.

Do look at the Alternator wire and see if it needs to be upgraded, You shouldn't have to open up the harness, just follow the harness around and make sure the wire goes to the Bat and nowhere else.

I would upgrade the converter, the one your looking at on ebay should work. Before you buy that one, check the web site I gave for "Best Converter". they may have something similiar.

JOhn Mc

88 Dolphin 4 Auto

[bestbowl]

Okay.

Which one of these do you think is best suited?

http://www.bestconverter.com/PowerMax-PM3B-100-100-Amp-3-Stage-Converter-Charger_p_472.html

http://www.bestconverter.com/100-Amp-Power-Converter_p_371.html

[waiter]

Call these guys on the phone, Tell them you want to upgrade your present converter, make sure you have the model number of your present converter.

I don't know if the two you referenced arte in a "Kit" or if these are just the power supply.

There's a little more to the upgrade than just hooking up the positive and negative wires.

Th e upgrade kit I got included a new rack that fit perfectly into the old rack, and also a new distribution board with fuses..

John Mc

88 Dolphin 4 Auto

[Maineah]

Our cop car alternators are 220 amp and they are feed with a #4 wire. Your alternator I believe is fused at 60 amps in the fuse panel under the hood and is feed with a #8 wire. You need some pretty big cables to get full smoke from the alt. and to charge your rear battery what you can do is feed the coach to a terminal block with a #2 (or larger) cables then drop to a lower gauge when you get there. You are asking a lot of your system what with the amp and the chargers so every thing needs to be maxed, find thebiggest terminal as far as wire size that fits the lugs and use that wire toyour truck battery from the alternator and Isolater skip the original alternator wire it's not big enough remove the fuse so it's no longer hot. 70amp charger is about 890 watts plus what ever wattage is lost to heat at 12.7volts so your generator will run it. Again the biggest wire you can stuff underthe terminal on the charger. If you are using your amp it's going to run down your battery no matter what you do there just is not enough to handle the load granted it won't use 2000 watts all the time but during peaks it will. I'm not sure how linear it is but it's still a lot of current. Do you have capacitorsin line with the amp cables? That will help. Again you are asking a lot soevery thing has to be perfect. A pair of golf cart 6 volts will give you something close to 225 amps and some 12 volt AGM's maybe 140-180 amps but you still need to recharge them.

[bestbowl]

The alt wire is a single #4 directly to the battery. It seems as the other harness of three wires may be the sensor you were talking about...?

[bestbowl]

Maineah,

I do not have capacitors. You think this will help? Maybe I will instal them if so. Can I feed the coach battery with a #2 (or more likely a #4?) directly from the positive terminal of the truck battery? And/or should I feed it with the new isolator?

[waiter]

If your going to leave the bike and stereo on the truck battery, there is no need to do anything to the coach electrical system, except upgrade the converter. This will allow the converter to do a high current charge on the coach battery.

Upgrading to the isolator you were looking at MIGHT allow you to charge the truck battery from the coach converter (I say might, because I didn't read up on that isolator to see if it will allow current flow both ways.)

HOWEVER, There is a very simple modification that you could do to your existing isolator that will allow it to go both ways. Add a manual switch to turn the isolator ON when the truck is not running. Keep in mind, if you forget this switch is on and run the coach battery down, you also run the truck battery down.

ISOLATOR OVERRIDE SWITCH

Mount a SPDT (Single Pole Double Throw) switch on the dash. Label it ISOLATOR, one position is AUTO, the other position is ON..

Remember - If you leave this switch in the ON position, it will kill BOTH your batteries in a day or two.

John Mc

88 Dolphin 4 Auto

[Maineah]

The caps smooth out the power demand they are sort of like a little storage battery that can dump power when needed and if you have an amp with that much power you need them. The smaller the wire number the greater the diameter so use the biggest you can and if you don't want a dead truck battery yes use the isolator. I understand you run the amp from the coach battery so you need to feed it with the biggest wire you can in order to properly charge it it's a long way from the alternator all though it does not seem so. 12 volts is tricky because of the loss you need very big wires to get max power to the other end a small percentage loss at 480 volts is nothing to worry about but that same small percentage loss at 12 volts is a big deal. Huge high tension towers have voltages in the ten of thousands of volts just because of the length of the run and the voltage loss, it is calculated but they have the benefit of high voltage to make up for the loss. Your set up is a huge energy hog so you need to compensate for that, normal MH set ups can easily get by with a #8 wire charging the coach battery yours can't same goes for the truck battery because of the demand from the charger for the bikes. Ideally you should have AGM batteries with high current output some I have recently seen can do 1,100 amps they are showing up in the state police cars but they are over $300 each so your system can get expensive fast.

[waiter]

Maineah;

I was under the impression that both the bike and the stereo were connected to the truck battery!

If this isn't the case, then the Coach also needs serious wiring upgrades. The existing 12 volt coach wiring is designed for loads in the 15 - 20 amp range.

John Mc

88 Dolphin 4 Auto

[Maineah]

I'm pretty sure he said the amp was in the coach but it maybe the other way around amp in the truck and the charger in the coach either way he needs some serious rewiring that's a lot to ask of 17 year MH that was built to run lights,heaters and water pumps. I'm thinking a 10KW built in generator!