I recently unplugged from shore power with batteries full, motored about 5 hours, and dropped the anchor for the night. I had consistent alternator/tach performance the whole time. When I restarted the engine in the morning the 440 AH house battery bank was down about 40 AH. Motoring out of the anchorage the alternator and tachometer were cutting in and out maybe every 30-60 seconds. During “off” times the battery monitor dropped from showing positive amps in to negative amps out. Turning on high amp draw items didn’t help. It took about an hour of motoring to stabilize to where the tach was staying on solidly and the alternator putting out consistently. I have a 20 year old Balmar external regulator and I’m considering trying the MC-614-H in its place – but I hope I’m not barking up the wrong tree?
Alternator and tachometer cutting in and out
- Thread starter 4arch
- Start date
Loose connections at the back of the alternator most likely. Anything intermittent in electrical is 99% a loose connection somewhere. The 614 is a neat unit.
Differences between Balmar MC-614 and ARS-5 Regulators
http://forums.catalina.sailboatowners.com/showthread.php?t=160744&#post1102540
http://forums.catalina.sailboatowners.com/showthread.php?p=1053410&highlight=ars-5
Differences between Balmar MC-614 and ARS-5 Regulators
http://forums.catalina.sailboatowners.com/showthread.php?t=160744&#post1102540
http://forums.catalina.sailboatowners.com/showthread.php?p=1053410&highlight=ars-5
Stu - Thanks for the info on the MC-614. I did see this quote from Maine...
"IMPORTANT NOTE: Voltage sensing and alt output MUST go to the same bank. Neither can be switchable or the reg will not see a bank getting charged and drive the bank being charge to 17+ volts. I see this quite often in DIY installs and also see the fried batteries to go along with it."
I'm concerned that my existing regulator is not installed this way. Right now the alternator positive output goes to an isolator. I assume the voltage sense “sees” either just the house bank or the combined house/start bank. It sounds like I might be better off getting rid of the isolator and having everything go to the house bank. Right now there is a Sterling BM12123 maintainer between house and start banks for charging off of shore power that I assume could stay in place for all charging of the start bank.
"IMPORTANT NOTE: Voltage sensing and alt output MUST go to the same bank. Neither can be switchable or the reg will not see a bank getting charged and drive the bank being charge to 17+ volts. I see this quite often in DIY installs and also see the fried batteries to go along with it."
I'm concerned that my existing regulator is not installed this way. Right now the alternator positive output goes to an isolator. I assume the voltage sense “sees” either just the house bank or the combined house/start bank. It sounds like I might be better off getting rid of the isolator and having everything go to the house bank. Right now there is a Sterling BM12123 maintainer between house and start banks for charging off of shore power that I assume could stay in place for all charging of the start bank.
Not only that, but the isolators, combined with the voltage drop in wiring to battery banks, mans you're not getting full alternator output and you are undercharging your banks.
Yes, get rid of the isolators, the Sterling is both isolating and combining your banks when required.
Isolators were/are so old school that I removed mine when I first bought our boat in 1998!
Even without isolators: ...make sure that the BATTERY SENSE wire from your regulator goes to your house bank. The instructions with external regulators gives you an option to connect it to the back of the alternator. This will NOT work, since it will be reading almost if not more than a volt LESS than if it was properly placed at your house bank.
I haven't read the ARS5 manual in quite some time, this is re the MC-612 I have.
Good luck, glad to help.
Also check how your regulator controls the alternator, if it turns the alternator off when it gets hot then the tack will go too (assumes the tack is running off the alternator and not a dedicated sender). does the regulator have an alternator temp sensor? Since the banks where very discharged the regulator may be sensing the alternator working hard and getting hot and shutting it down to protect the alternator.
I ended up purchasing an installing the MC-614. It was a pretty easy swap for the old ARS-2 I ended up pulling out. I ended up rerouting the wiring harness so I could locate the unit outside the engine compartment. The charging function seems to be working much better with the new regulator, properly going into bulk, absorb, and float without bouncing all over the place like the old one. Unfortunately I'm still having issues with the tach. If I start with the battery full and the unit goes straight to float, I have no tach. I attempted to route the stator wire through the 614 but then had absolutely no tach or hour meter. At least with the stator wired directly to the alternator I have it when there is a load on the alternator. So I'm now curious whether the built in tach function on the 614 simply isn't compatible with the old non-Balmar alternator I have, or if there could be some other issue at play here?
I am going to guess you have a solar array. When the batts are full your solar controller voltage is likely a tad higher than the Balmar and thus shutting the alt down. Set the solar controller at a LOWER VOLTAGES than the regulator and see what happens. Both absorption and float should be lower on the solar controller than the MC-614, if you want your tach to work..
Try pulling the fuse on the solar and see what happens. The MC-614 should be fully compatible with any alternator that has a stator / AC tap. Probably just a wiring blunder... Still won't work though if the reg shuts down the alt...
Try pulling the fuse on the solar and see what happens. The MC-614 should be fully compatible with any alternator that has a stator / AC tap. Probably just a wiring blunder... Still won't work though if the reg shuts down the alt...
Connection corrosion
Contact cleaner has solved most of my electrical problems. Hunter 40.5 built 1995. Intermittent starting / unreliable tach / Balmar sometimes . . .
Contact cleaner has solved most of my electrical problems. Hunter 40.5 built 1995. Intermittent starting / unreliable tach / Balmar sometimes . . .
I had a similar issue with my tach only. My tach comes off a sender on the flywheel. I ended up cleaning all the connections with a small file and actually replaced the spade connecter on the wire. It fixed my tach issue. If your tach comes of the alternator then this doesn't necessarily apply. I had charging issues from my alternator and smart charger, actually killed two less than a year old 200 ah batteries. The problem turned out to be the buss bar that the negative battery cable went to that distributed ( or is the buss connection for negative wires or cables at the battery end had broken the plastic that the mounting studs were encased in and made intermittent contact to the battery cable to the batteries. I had to get towed in to my marina one day because the connection had lost contact because of the sailing motion of the boat. Started at the battery and followed the cable to the buss bar and when everything wiggled at the buss bar figured that was the problem. Replaced the buss bar and all is right with the batteries and boat.