Pete1122 Posted January 24, 2015 Share Posted January 24, 2015 I just purchased a fancy Clipper Battery Monitor for my charging system, I have struggled keeping my coach batteries charged while driving and I thought this would help me figure things out. According to the monitor my alternator at idle is only charging at 3 amps. Keep in mind that all my wiring has been upgrading to quality 4awg, and my grounds are upgraded including my isolator is new. Bad alternator right? I mean what else could it be? The other thing that alarmed me was my Fridge while on electric using my inverter consumes 35 amps. Quote Link to comment Share on other sites More sharing options...
Vanman Posted January 25, 2015 Share Posted January 25, 2015 If the battery is near fully charged that would be correct, once fully charged the current should drop to around 1 amp per battery. Is the charging system charging the Toyota battery OK ??Is the shunt for the meter in series with the alternator output or in series with the coach battery feed?? Quote Link to comment Share on other sites More sharing options...
zero Posted January 25, 2015 Share Posted January 25, 2015 The other thing that alarmed me was my Fridge while on electric using my inverter consumes 35 amps. You're not confusing "inverter" with "converter", correct? If you are using a 120 volt AC refrigerator hooked to an "inverter" in your RV - 25-35 amps @ 14 volts DC draw is normal. If you are using a 12 volt DC refrigerator hooked to a "converter" you're wiring might be wrong. Conventional RV wiring usually does not allow a three-way refrigerator to be hooked to the converter/charger/power-center. It usually bypasses it and gets hooked to a direct feed. Regardless - normal draw for a three-way when used on DC electric-mode is 8-10 amps @ 14 volts DC. I think trying to check alternator charge the way you are doing it will be misleading. All you need is a voltmeter. Any reading above 12.7 to 12.9 volts means the alternator (or converter/charger) is charging. Normal voltage when all the batteries are charged and engine is running is 13.8 to 14.2 volts. Quote Link to comment Share on other sites More sharing options...
Maineah Posted January 26, 2015 Share Posted January 26, 2015 The current of an alternator is voltage dependent this is why there are no longer amp meters in vehicles just battery voltage meters. If the battery voltage is up to snuff the current is down. One thing you might check is the belt tension if it can't keep up. Quote Link to comment Share on other sites More sharing options...
Gulfstream Greg Posted February 4, 2015 Share Posted February 4, 2015 Here is the manual for the clipper which has a wiring diagram to use with two batteries. http://www.nasamarine.com/images/Clipper%20BM1+BM2.pdf What I see is that the second (coach) batteries negative side only connects to the shunt. No connection to chassis. As a note here I have seen bad chassis grounds create charging problems with second batteries. If your starting battery never seems low on charge then it is possible the system is not seeing the coach battery properly. Start your engine several times in a row with the headlights on then with the engine running start checking voltages at all points, IE both sides of the isolator, starting battery, at the coach battery, at the shunt, positive and negative posts, positive and chassis etc. Quote Link to comment Share on other sites More sharing options...
Totem Posted February 4, 2015 Share Posted February 4, 2015 if truck battery is getting charged and coach not first thing I would probe would be the solid state isolator or the solenoid separator of the batteries. I had an isolator go bad that did exact same thing. no charge at all to battery 1 and battery 2 was fine... for a while then it too went bad. replaced alternator and then it "cooked" the black gel that is inside the isolator and it started smoking; that was how i found out it was the culprit. I have changed alternators 5 times now in my rig in past 4 years. i can do it blindfolded and keep a spare. my fridge used to eat them; now i do what waiter suggested and run on propane; even when driving. 12 volt on fridge is silly. Quote Link to comment Share on other sites More sharing options...
Gulfstream Greg Posted February 6, 2015 Share Posted February 6, 2015 I used to run our sunrader refer on 12vdc, had a aux lighting relay that gave the refer power and that I could turn on and off from the dash. Had a led on the dash that was powered from the refer side of the relay so I could verify the refer was getting power in case the relay failed. Seems like it was around 8 amps or so for the refer, really not that much, not enough to smoke the alternator but enough to run the coach battery down in slow traffic or parked so that was the reason for the switch. I have been through 4 alternator on our V6. First one had a bearing failure, second one shorted on got so hot it was smoking, third one smoked when the isolator blew up. So far the 4th one is still alive. Quote Link to comment Share on other sites More sharing options...
zero Posted February 6, 2015 Share Posted February 6, 2015 A stock 80s Toyota is going to have the ability to charge 28-30 amps with the engine at idle speed. Running the 3-way refrigerator on 12 volts, only drawing 8 amps, should never be an issue unless there are a lot of other draws on the system. Driving at night with the AC on, and the headlights and tail-lights on, yes. Quote Link to comment Share on other sites More sharing options...
Pete1122 Posted February 6, 2015 Author Share Posted February 6, 2015 I have what you would consider "Heavy" electrical demands in my Motorhome. I have the following running off a 1000 watt pure sine Inverter while driving. 1. Refrigerator 2. Xbox 360 3. Wii 4. Laptop 5. Gaming chair At the same time I have the following running off my 12 volt system not hooked to the inverter: 1. 24" LED TV 2. DVD Player 3. Various LED lights and USB chargers 4. Two small fans 5. Back up camera 6. Back up video screen 7. Tire Monitoring system 8. iPad/iPhone chargers 9. Powered Subwoofer I have upgraded my entire charging wiring system to heavy 4awg wire, grounds to 0awg and upgraded the Isolator. In addition I run two 6volt batteries. I just finished installing a custom 120amp alternator upgrade to help support all this. Quote Link to comment Share on other sites More sharing options...
zero Posted February 6, 2015 Share Posted February 6, 2015 Yes indeed, you've got a lot. No way can a single V-belt turn an alternator to make 120 amps but I assume you're now getting around 50 amps at engine idle speed? I ran by Chevy Blazer RV for years with a 4.4 cubic foot AC refrigerator hooked to an inverter. It had a 72 amp Delco that could charge 30 amps at engine-idle. I could drive at night with all the lights on and it never showed a discharge at engine-idle. But I had no other electric loads to speak of. Diesel engine with mechanical injection, mechanically shifted trans, etc. My old Samsung AC refrigerator when hooked to the inverter draws around 9 amps @ 14 volts DC when running. Quote Link to comment Share on other sites More sharing options...
Vanman Posted February 8, 2015 Share Posted February 8, 2015 If you run the Refrigerator off the propane tank might that drop your load down to what the stock system can handle??/ Quote Link to comment Share on other sites More sharing options...
Pete1122 Posted February 9, 2015 Author Share Posted February 9, 2015 If you run the Refrigerator off the propane tank might that drop your load down to what the stock system can handle??/ I'm sure it would, however my fridge wont stay cold on propane. I'm going to dump it and throw in a mini/dorm fridge. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.