150 Controller stuck at 16 volts

[andyrud]

Hi everyone and sorry for the long post,
I am a new poster and need some help with my Midnight Solar 150 controller.  I have the highest Voltage set to 15.3 volts to charge my 12 volt battery system BUT the controller allows the voltage to go to 16 volts.  I reset all voltages, bulk, absorb, equalize, to 15.3 volts but it still allows the voltage to go to 16 volts.  The battery system is composed of six 6 volt golf cart batteries one year old in series/parallel to make 12 volts and my panel array is at 24 volts.  I purchased this controller approx.. 10 years ago, I think it was one of the first ones out.  It has never been firmware updated.  It has served me well until now.  I think maybe it cooked my batteries.  Any ideas as to what I should do?  Has anybody had or seen this before?
Thanks in advance,

Andy Rudovsky

[niel]

it hasn't quite been 10 years i don't think, but maybe you have the bts set for too far in mv compensation on cold batteries or maybe it's right as i've seen mine go high on a few cold nights. if in doubt it's the bts and it's connected then disconnect it and see what it goes up to then.

[andyrud]

it hasn't quite been 10 years i don't think, but maybe you have the bts set for too far in mv compensation on cold batteries or maybe it's right as i've seen mine go high on a few cold nights. if in doubt it's the bts and it's connected then disconnect it and see what it goes up to then.

Ok, great idea, I never thought of it.  The temperature in the battery room was about 45 degrees f, but at night it went down to about 38f.  Thanks for the reply.

Andy

[TomW]

Have you calibrated the controller input voltage?

Maybe check what a volt meter thinks the battery is at and at the controller?

Just what my first steps would be. It can be adjusted in the "tweaks" menu

Tom

[andyrud]

Have you calibrated the controller input voltage?

Maybe check what a volt meter thinks the battery is at and at the controller?

Just what my first steps would be. It can be adjusted in the "tweaks" menu

Tom

Thanks Tom, I did that and they were in sinc.

Andy

[ClassicCrazy]

I agree with Neil, check what the battery compensated voltage is - there is a place to see that on the MNGP and also if you look at Local Status app under Config/Tech/ battery comp it will show it.  The colder the batteries get , the higher the charging voltage will be. Depends on what mv setting you have in the temp comp setting too. I think default is -5 mv but you want to set it to your battery manufacturer specs.  Without temperature compensation cold batteries will never charge up all the way and will be ruined - I learned the hard way on my first small system !

You meant that you only have the equalize set to 15.3 v ?  That would be way too high for absorb and float voltages to be.

Larry

[andyrud]

I agree with Neil, check what the battery compensated voltage is - there is a place to see that on the MNGP and also if you look at Local Status app under Config/Tech/ battery comp it will show it.  The colder the batteries get , the higher the charging voltage will be. Depends on what mv setting you have in the temp comp setting too. I think default is -5 mv but you want to set it to your battery manufacturer specs.  Without temperature compensation cold batteries will never charge up all the way and will be ruined - I learned the hard way on my first small system !

You meant that you only have the equalize set to 15.3 v ?  That would be way too high for absorb and float voltages to be.

Larry

Thanks Larry, I reset all the various voltages to 15.3 volts to test if the controller still went to 16 volts.  After it did I returned the voltages to their normal settings. 

Andy

[Westbranch]

Andy, can you do an update?  Since it seems to be 'stuck' I would do an update and see if that cures your problem...
there was a new version posted last night.

good luck. 

[andyrud]

Andy, can you do an update?  Since it seems to be 'stuck' I would do an update and see if that cures your problem...
there was a new version posted last night.

good luck. 

Thanks, I probably should do that.  I have never updated the the controller since I bought it.  I guess I will have to read up on how to do it.  Is  it hard or tricky to do?  It is in the mountains and no wifi available, so, I will need to download update to my laptop and install it that way.  I guess there is a way to do this? 

Thanks,
Andy

[Westbranch]

What type of computer do you have?  I use a laptop with W7, the latest 2 or 3 versions can be done on W10.  there are a few wrinklles depending on the version.
There are instructions to follow and you have to do it exactly to them or ...  

let us know which you have so we can comment further.

[Vic]

Hi Andy,

IMO,  it would be very good to have Internet access available at the place that you are doing an Update of the Classic Firmware.   Having access to this Forum can be a valuable  asset if you need help.

The first Classic in use here,   was from the first Production run (and available for purchase by the general public)  was ordered just before Christmas 2011,   and was shipped,  Jan 2012,   FWIW.

The later versions of Firmware have many added useful functions,  so an Update should be a benefit to you.

IMO,   Vic

[ClassicCrazy]

Depends on your computer skill level as to how hard the firmware update is.
The new update software seems to work a lot better than the older version.
But you should make a printed copy of how to do a hard reset of the Classic  using the jumpers - just in case you hit a snag.
You also want to know how to do the software reset known as the VMM which you will need to do after you do the firmware update. To do that you hold the left and right arrows in on the MNGP while turning the power on . It will erase all your old settings so you need to write down whatever you have in there first if you can't remember so you can  enter them in again.

As others have said there will be a lot of new features in the updates if you have never done one before !

Larry

[Westbranch]

As others have said there will be a lot of new features in the updates if you have never done one before !.

Right! on that note do you have a WhizBangjr (WBjr)?  if not, it is a very valuable addition to the Classic as it lets you have a much better view of how your solar project is performing...and to be more exact it tells you how much of your PV production (amps ) actually goes into the batteries, not just what the Classic sends towards the battery.  Most recommended...

So before you head out into the sticks, can you get one for installation?...

hth

[andyrud]

What type of computer do you have?  I use a laptop with W7, the latest 2 or 3 versions can be done on W10.  there are a few wrinklles depending on the version.
There are instructions to follow and you have to do it exactly to them or ...  

let us know which you have so we can comment further.

I have a Microsoft Surface Pro 3 running Windows 10.

[Resthome]

You will need a USB cable that came with the Classic.

Also download the latest Instructions for Win 10 from the MN web site. Both the Win7 and win10 Instructions have recently been update as MN is only providing the new Programmer package for the firmware.