battery drain or bad monitor ??

[bob_deb]

Hi,

I don't know much about batteries, yet, so here goes ---
I have a start battery on one bank and 2 batteries on the house bank.
I have a Link 20 Battery Monitor. The house bank apears to be okay but the start always shows a 4.2 amp battery drain. I can have everything off and have the selector switch in the off position and it still shows a drain.
Both banks usually show the same or nearly the same volts, arounf 13.2.
But the start battery will be flashing red on the monitor and loosing about 4.2 amps. I disconnected the red or positive cable from the battery and it still showed a drain.
Am I loosing amps in a mysterious place or do you think my LINK 20 is bad ???? And how do I test it ?? A new Link 20 can run over $200.00
thank you all
- Bob

[Sandero]

Try to disconnect ALL the pos wires to the Link to reset it. Then see if it provides the same reports. When it comes back on it the display flashes and you have to re enter the battery type and capacity in the set up routine.

[Blue Stocking]

4.2 amps sounds suspiciously like a field current to the alternator. Do you have an externally regulated alternator switched on from a relay or oil pressure switch, which may be faulty and not disconnecting? Is the alternator warm when the engine is cold.
I would go defjef's route first.

[Sandero]

IIRC the maxcharge612 is wired via an oil pressure switch so that the regulator comes one (get power) when the OP switch closes. This sounds like a fair amount of current draw. No?

[bob_deb]

Hey defjef and Blue Stocking and everyone else,
thanks for your initial responses !!

Let me tell you what all I have and maybe this will help.
I have a Volvo MD11C 23hp with a Balmar Alternator, 1 start battery and
2 house batteries that I think were purchased in 2003 and probably need to be replaced.
I checked the Alternator and it did not feel warm, I disconnected the batteries from the LINK 20 and reset everything.
I still show a constant drain on the start battery that is closer to 4.6 amps.
Blue Stocking suggested it may be a field current to the alternator ??
I'm not sure what that is but if you can tell me how to check for it I want to give it a shot.
Also, the Balmar alternator, from my understanding, is set to be in a soft ramp up mode for the first 36 minutes, would this explain why my volt meter needle is between 10 and 12 and not in the normal running range ???
If you havn't guessed by now, I have had this boat for only a short time but I do need to learn.
thanks - Bob

[David M]

This is easier said than done. You need to get a multimeter and set it on the current setting...probably in milliamps. You then need to measure the current draw starting from the battery and working your way towards the tiny load that is drawing down your batteries. Your going to have to keep disconnecting, measuring across and then reconnecting things until you get right down to the load. If its the alternator itself it may need a new regulator and/or a rebuild. Diodes can fail on them. That is a possibility as well.

Run your alternator and set your meter to the AC setting. Is your alternator creating any AC? A blown diode a rectifier can cause this.

[Sandero]

I would also disconnect the balmar alternator. On the back there should be a large (probably red) cable which is carries the high amp charge TO your batts. You need not remove that. But there should be a smaller (probably red) wire which "energizes" the field and is probably connected to the key switch so that.

You didn't say if you have a balmar regulator like a maxcharge. But if you do don't mess with the alternator, just remove the +12v wires to the maxcharge. This means that no current will energize the field and you won't be charging your batts when you run the engine. But now LOOK at the link and see if there is any drain (4.6amps) If there is, it's not the maxcharge regulator.

Perhaps you have a short or defective solenoid. This is also connected to the key switch and when you turn the key switch to the momentary ON position it is supposed to energise the solenoid which pulls it to engage the gear teeth. When you let the key go when the engine starts, the start motor retracts. Perhaps the drain is from the solenoid being constantly energised even when the key swtich is off!

Try the above and report back!

[bob_deb]

Thank you all so much, this will keep me busy I'm sure, till after all the guests head back North after the Holidays.
I will get back to you then to give a report.
thanks again
- Bob

[Sandero]

If you have a means to remove one "load" at a time eventually you will find the guilty culprit. It may turn out to be a defective piece of equipment or a wiring error.

If your problem is on the start battery circuit, trace all the wires that connect to THAT battery. Logic says it has to be somewhere in that "mess".

When I changed my power wiring I srt it up so that the start battery ONLY energizes the starter motor. The solenoid and other loads on the key switch, such as the engine room blower and instrument lights were moved to the house bank. The solenoid is the "switch" (relay) which connects the starter motor to the battery. My volvo wiring originally had the key switch and the loads connected to it on connected to the common on a one/two both switch. That meant that I could start with batt 1 or 2 or both.

I changed that too. I have a small start bank and a large house bank. The alternator and other charging devices charge the house bank. The start bank is charged by an inexpensive device called an echo charge which takes a bit of current from the house bank and charges to start bank. My start bank is virtually always fully charged. The Blue Seas battery switch I use can combine the house and start bank which is like a both position. I never use that combine feature.

A 4.8 amp drain is not something you want, so you need to get to the bottom of it.

[bob_deb]

Okay !
I can't wait till after the holidays, this thing is bugging me,
so I'm headed out now, as soon as the sun gets up anyway
to start checking it out. I will start with disconnecting the regulator first and go from there. Yes I do have a Balmar Regulator.
thanks
- Bob

[bob_deb]

Hi defjef,

I disconnected the Maxcharge regulator and still had a drain 0f 4.6
on the start batt.
Does this rule out both alternator and regulator ??
Just to see what might of happened, I disconnected the red (+) cable of the start batt and the drain still showed on the Link 20. I then tried same with the neg cable, still same -4.6 , does this mean anything ??
All the while, I left the wire on the batt that connects to the Link 20.
Should I disconnect the Link 20 for a day or 2 to see if that is where the drain is ??
If this dosen't mean anything then maybe it is the solenoid ??
Can you let me know, and how do I check that ??

thanks - Bob

[Sandero]

You are taking the correct approach.

To reset the link you only need to remove the fuses (3 I think) or disconnect the pos wires and the display should go blank. Leave it off for a few minutes and then you can reconnect and go through the set up program.

Assuming that when you reset the Link and you still see the -4.6 you now have to determine if the link is whacked up or there is some drain in your wiring.

Let's see which battery is being drained. Disconnect the battery cables, at the battery, first from the house and then the start bank. Check to see if the reading on the link changes. If the batteries are not connected, ie no loads are receiving power from the batteries the link should show no neg amps. If it does it would be the link. remember to remove any loads connected to the batteries. Some are wired directly to the battery and not the common on the selector switch or a Pos buss, such as the bilger pump or a propance solenoid. If you remove all the pos wires from the batts in sequence when the guilty device's pos wire is removed so will the neg load you are seeing. If every wire has been removed and the link is only monitoring the batteries themselves and there is a drain, it would sound like the monitor... no? The link itself will be a tiny drain, but nothing like -4.6 amps.

Give this a try.

[bob_deb]

hey defjef,

thanks for all your time and patience.
Here goes -
I first disconnected the house bank, pos cable only, link still shows drain.
next, the bilge pump - still 4.6 amp drain.
third, leaving off house bank and bilge pump, next was start batt,
still showing drain.
The only thing connected to batts is link 20 and black neg(-) cables.
My guess would be that the Link 20 is broken, or it is causing the drain ???

Today the start batt is showing 13.05v and the house 12.70,
IF there really is a drain and not a bad Link, should one or both of the batts show less volts within 24 hours ??? I'll go back and look at it tomorrow.
My next thought would then be to disconnect the link altogether for 24
to 48 hours to see if it does drain.
Do you think this will work ??? any suggestions ??
thanks - Bob

[scotte]

Might be worthwhile to carefully check the wiring at your shunt for any corrosion or bad connections. Wiring issues between the batteries/shunt and the monitor could potentially cause faulty readings.

[Sandero]

I second checking the shunt connections. With NO loads connected at all there is no reason to measure any so it has to be an "artifact", a bad connection in the wiring or the unit itself - even the fuse holders! I don't think 24hrs is required to reset the link. but it should be OFF completely for a few minutes and when it come back on it has to be blinking and then RESET. You're supposed to do the set up with topped off batts, but you can do that again when they are topped off. First you want to find that -4.6 amps.

If you are certain that NO loads on the battery BUT the link are connected to your electrical system then it is the LINK and / or the wiring of the LINK. You might have to "redo" all crimp connections. If it restarts with a -4.6 amps and ONLY the link connected to the batts it's gotta be the Link unit.

Merry Xmas!