checking charger output [Archive] - Walleye Message Central

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boater

10-12-2009, 10:06 PM

I need to check the output of my onboard charger to see if one of the banks is charging correctly. Can this be done with a simple multi-meter. I have one from radio shack that has the following choices of measurements- ACV, DCV,OHM,DCA
The charger is a 3-bank, 10amp/bank (30amp total). I have one bank that is not showing charged and need to determine if it is the charger or the battery. Bank #1 shows charging while banks #2 & #3 show full charge on the indicator lights.
I checked the voltage of the 3 battery's using the above multi-meter set on DCV-20V and got the following readings: batt 1-12.10, batt 2-13.60, batt 3-13.60 (the battery numbers correspond with the charger banks above).
Can the output of the charger be checked using this meter? If so which of the settings from above choices do I need to set it on. I was hoping to compare output of all 3 bank leads to see if bank #1 was lower..

Thanks for the help.

perchjerker

10-13-2009, 04:27 AM

switch the leads on one of the higher readings with the lower one and see if the problem follows the leads. if it does it the charger, if its still low on the same batt then that batt is suspect

Crankbaiter

10-13-2009, 05:53 AM

If the one lead that is not behaving properly is connected to the starting/electronics battery and the other two are connected to the trolling batterys (if it is a 24 volt system) then you might want to check to see if there is a draw on that starting battery.

If somthing is on then it may not achieve a full green charge light.

PerchJerkers suggestion is a good one. When you disconnect the suspect battery touch the leads back against the posts and look for an agressive spark that would indicate there is a draw.

yarcraft91

10-13-2009, 06:03 AM

Do like Perchjerker said- it's the simplest way to get a direct answer. If you want to measure charger amperage output and your multimeter has a 10 amp DCA setting, you could remove the charger lead on the + battery terminal and use the multimeter (set at 10 amp DCA) to connect between the charger lead and the battery + terminal. That will read out the current flowing to the battery. But, in the time it takes to do that, you'd have the answer from PJ's approach.

Boater

10-13-2009, 08:33 AM

All three battery's are for trolling motor, 36V system. Just to make sure I understand what your saying to check Perchjerker, you are saying to switch the charger leads from batt #1 (this bank #1 shows "charging") with the leads from batt #2 (this bank #2 shows "full charge") and see if bank #1 still shows "charging" even though it is now hooked to a battery that measures 13.60V and showed full charge with original lead hook up?
If this does happen I see your point that then this would indicate that bank #1 probably died. If so could it have possibly died during charging and this is why the battery #1 that was on that bank is not showing a full charge (12.10V)? I assume that if this is the case that when these leads are switched around and a working bank is placed on the battery showing partial charge (12.10V) that the new bank hooked to that bank will also now show "charging" since that battery is not fully charged?

Thanks you guys for all the help, it is appreciated.

yarcraft91

10-13-2009, 09:53 AM

PJ is pretty good at speaking his own mind, so I'll just tell you what I'd look for.

Battery #1 shows 12.1 volts. Battery #2 shows 13.6, so Bank #2 clearly works.
Disconnect Bank #1 from Battery #1 and hook Bank #2 to Battery #1 instead.
If battery #1 now charges to 13.6 volts, Bank #1 of your charger is dead.
If Battery #1 still does not charge up, Battery #1 is dead.

perchjerker

10-13-2009, 04:21 PM