Battery noise

System

Sounds weird I know but I'm getting a high pitched whine coming from my batteries. Is this normal? I don't remember ever hearing one before and it stops when I remove the negative battery clip from the controller. Unrelated, I also have to reset my meter as it's recording a constant draw that shows up on my accumulative amp draw display. The meter shows the bats at %70 yet my voltage is at 13.7v, at night. I know the charging is working, due to the voltage, but why won't my meter reset to %100 when it reaches 14.2v? Probably something simple that I overlooked. Thanks. :-D

System2

Re: Battery noise

Noise is probably the result of the controller switching the input from the PV's in the PWM control mode. My setup does that too, but with mine, the noise comes from the controller and it's associated cables between it and the batteries and panels.

niel

Re: Battery noise

shawn,
i'm wondering if that might be the batteries outgassing. as the gas goes through a tight space it may be whistling like a tea pot. how do your pvs give a charge to the batteries with a 13.7v reading at night? i'm not sure of your meter not resetting.

System2

Re: Battery noise

Actually, the noise only happens during the day, during charging. Did I forget to mention that? They're sealed batteries so where the gassing comes from I wouldn't know. It's just funny how the battery bank is showing a good voltage and the meter says I'm down to %70. I wonder if the controller isn't cutting off at the right time to let the meter see the 14.2v peak. (The voltage I have it set to as a %100 level). I've gotten around this by using a charger to bring the bank up to 14.2v, then the meter sees this and resets. After about two weeks I'm back to where I was.
  It may be related that I have yet to remove my faulty inverter from the bank, (different thread). Could a faulty inverter draw power even when turned off? I just don't see where the slight draw is coming from that's been showing on my meter, just not the batteries. As I said in my other thread, I'm waiting on a response from Xantrex before I replace my inverter. I want to see what they say first. What I should do is remove the bad inverter first and see if this is the culprit. I just haven't the nerve yet to dive into that tight box of close wires and voltage and play operation.  :-D

System2

Re: Battery noise

Yes, depending on how the inverter failed, it could very well still draw current.
You mentioned two things, re the noise.
1) only happens during daylight.
2) it's charge voltade is rather low - too low in my opinion.

Question
1) is your controller use PWM? If yes, When does the buzz start? As soon as the sun comes up? or after the batteries have been charging for a while?

niel

Re: Battery noise

shawn,
to be honest with you this doesn't sound good. be very sure that it is coming from the batteries and not the controller. i think wayne was driving towards the pwm frequency of the controller. you indicated a high frequency though and most controllers are around 300hz. if it is from the batteries i would be at a loss to explain it happening in a non harmfull way, but my fingers are crossed. take the positive lead of the suspected faulty inverter out of line to see if it clears up any troubles including the whining.

System2

Re: Battery noise

I noticed the noise over the weekend and since I'm at work during charging hours, it won't be until this coming weekend when I can hear when it starts. I have removed the inverter and, son of a gun, the inverter works connected to a portable 12v power station. At first the voltage alarm came on immediately, then I switched it off. Turned it back on and the alarm hasn't came on since. Been running the inverter with a small load for about an hour and works like a champ. My voltage in my bank is a steady 13.8v about 3 hours after seeing any sun. I'm going to reset my meter tonight and see if the batteries continue to lose voltage without the inverter connected. (Please just let it be the inverter....) :-P :-P