| Author | Message | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1580 Registered: 7-2006 Posted From: 97.224.107.228  Rating: N/A |
We have an "issue" with the generator charging it's start battery. Question: ...is there any reason why I should not connect a battery charger to that battery while the generator is running? I am thinking of a 6 amp charger, three stage...or a charger that has multiple amp options. Thanx.  RCB | ||
| les marston (Les_marston)
Registered Member Username: Les_marston Post Number: 364 Registered: 1-2010 Posted From: 68.151.225.213  Rating: N/A |
If the battery is not being charged by the generator, there is no reason not to use an external charger on it powered by the generator or by pole power. If you spend a lot of time on external power make sure you use a smart charger. Hook it up and forget it other than to clean the connections as regular maintenance | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 1371 Registered: 11-2005 Posted From: 173.202.30.60  Rating: N/A |
It depends. Some gensets have a built in very low amp charger, some don't. If yours has a built in it might not be compatible with a separate charger, I don't know for sure though. I had an Onan with a built in on the flywheel and had it connected to the bus starters. It gave my bus alternator fits until I disconnected it and used a separate small lawnmower battery. I made this separate battery connectable to the bus starters by a solenoid in case it got too low, worked well. | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 1543 Registered: 3-2007 Posted From: 76.4.118.199  Rating: N/A |
RC Check your voltage on the battery before you start it and then after you start the genset. If the meter shows more voltage after you start it your generator is trying to charge the battery. If it doesn't check to make sure it has the capability to charge a battery.Check da book on that. Gomer | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1582 Registered: 7-2006 Posted From: 97.224.107.228 Rating: N/A |
The generator is an Onan NH 6500. It has a charging system. I have the manual and have checked all that they recommend. They state it should charge at 1.5 amps.... The battery is new (last week). 700 Cranking amps, tested prior to purchase 12.98 volts, 865 cranking amps. Now, after three days of starting...two to three times a day, down to 12.01 volts (and that, today, after sitting a day with no use) Last attempt, yesterday morning, it started the set but was "on it's last leg". I carry a spare, and the same is happening to it. My thought is to use a small charger while it is running until I can get it home and go thru the thing thoroughly. It could be a diode, but I just don't want to mess with it at this time. Of course, I can disconnect the built in system if necessary. What I am asking, at the bottom line, is ....is there any conflict IF both genset and a charger are charging the battery at the same time? RCB | ||
| les marston (Les_marston)
Registered Member Username: Les_marston Post Number: 365 Registered: 1-2010 Posted From: 68.151.225.213 Rating: |
It is not likely to cause a problem for either charger however to be sure disconnect the built in one and use the external charger till you get home. Personally 1.5 amps to recover the amps used to start an engine doesn't excite me much you might want to check if there is any drain on that battery other than starting your generator. It sounds like it went flat very fast. by your numbers that would only be 9 starts of a small engine off of a fair sized battery. I have had more than one charger hooked up to a 12 volt battery before with no ill effect. Worst case would be for one of them not to try to charge a battery that it saw as fully charged due to the higher voltage being put in by the other charger. Just my thoughts and 1.95 cents worth | ||
| George M. Todd (George_todd)
Registered Member Username: George_todd Post Number: 1290 Registered: 8-2006 Posted From: 99.29.76.231 Rating: N/A |
Chuck, Gus and Les are both right. With two working chargers, one may well cause the other to stop charging, or they may both go on and off rapidly, but they won't hurt anything. A 1 1/2 Amp charge rate is squat! After an HOUR of running, you would have put 1 1/2 AMPERE HOURS back in your battery. In perspective, if the generator required 50 Amps to crank, and it started in 10 seconds, that would equate to about 9 Ampere Hours. A 10 Amp AUTOMATIC battery charger will do fine, don't spend a whole lot of money. What I would strongly consider is a diode separator or two, (I know you don't like them,) one between the house batts and the gen set. That way you will have all the amps of your inverter charging the gen batt. I personally don't use a gen batt, mine is on the chassis batts. G | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1583 Registered: 7-2006 Posted From: 97.215.44.130 Rating: N/A |
Interesting comments...and very helpful. Thanx, Mucho!!! I was thinking the same about the wimpy 1.5 amps. George, my genset is located a LONG way from the inverter...probably 25 feet or so. I have considered what you have done, but felt that was asking a bit much of the charging system...or???? (the present set up, inverter to house set requires about 10 feet of leads; AIR I used #6 wire). Thanx, RCB | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 1375 Registered: 11-2005 Posted From: 173.202.3.164 Rating: N/A |
My Onan manual said never to run the gen without a battery attached. Makes sense since this is an alternator. Again, I just attached a small lawnmower battery to the genset which I could connect to the bus starts via a solenoid, then I could charge the gen batt with the bus alt when it got low. I only did this when the gen was off. | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1585 Registered: 7-2006 Posted From: 97.215.44.130 Rating: N/A |
Upon further consideration, what might HEAT have to do with the charging...and the battery itself? This a pretty tight enclosure, however lots of air circulation...albeit, mucho heat! Gus...exactly what I have read. I doubt the thing would run without one. I pulled the negative cable a couple of days ago and it stopped. I just need to set it up so that when it is running "something" charges the battery, which has been answered above, thanx to you folks. My intention now is to do away with the internal charging mechanism and do as George suggested. RCB | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 1379 Registered: 11-2005 Posted From: 75.121.202.216 Rating: N/A |
RC, My Onan alternator was built into the flywheel, embedded I think, but I suppose you could disconnect the sensor mounted at the rim of the flywheel. | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1593 Registered: 7-2006 Posted From: 97.227.24.197 Rating: N/A |
hmmmm...I'll check that out. Mine is an NH6.5 Thanx, RCB |
