Check the Cable and Try Again

[ddxv]

I've been unsuccessfully trying to update the firmware on my classic 250 and I must be missing something. I have followed the instructions for Windows 7 install several times always with two failed outcomes: Upload Failed. Check Cable and Try Again OR COM8 May Already be in use.

To turn the Classic off I have been using Menu>Mode>Off, then following the instructions I receive this error after selecting Update Classic 250V: Upload Failed, Check Cable and Try Again

But if I leave the Classic powered on and then after selecting Update Classic 250V, plug in my USB (after several minutes) I get the error that COM8 may already be in use.

All help is appreciated, thank you

[dgd]

To turn the Classic off I have been using Menu>Mode>Off, then following the instructions I receive this error after selecting Update Classic 250V: Upload Failed, Check Cable and Try Again

All help is appreciated, thank you

You need to power off the Classic by opening the breaker between it and your battery bank.
ie removing power from it NOT changing the firmware mode to OFF

dgd

[ddxv]

Ah, Thanks for the reply dgd. Although I don't have a breaker between the batteries and the charge controller, I was able to successfully update the firmware by unscrewing the Batt + cable / rescrewing it in.  A little tricky but worked well.

Thanks for the help! 

[Vic]

ddxv,

Was hoping that the reason that you were not un-powering the Classis was because you had no breaker.

Well  then,  you MUST have a fuse!  Otherwise you could have a FIRE,  as you probably know.

You MUST have an Overcurrent Protection Device between the CC and battery,  and it is a very good idea (and required by code,  as I read it) on the input side of the CC.

High current DC circuit breakers are very inexpensive these days,  and,  having only  a fuse is a PITA  when trying to Update Classic FW.

The folks at MN are quite good about doing continuous improvements in the Classic CCs via FW Updates,  so  would bet that a circuit breaker would be a nice enhancement in your system.

BUT whatever you do,  you MUST have protection of some kind -- circuit breaker or fuse -- on the output of the CC,  even when it is a Classic.

Vic,  with attitude.

[zoneblue]

Do as uncle vic says. The reason we have a breaker there is this.... If the charge controller for whatever reason, one of the blue, worst case scenario, failed internally, charge controllers fail in one of two states, open or short. If its the latter with no fusing between controller and battery and you will proceed to dump the entire contents of your bank through the controller. Normally that wire would be at least 6 gauge. 6 awg will heat and melt to the point of fusing at around 660 amps.  Depending on the internal resistance of your batterys, typically about 1 or 2 milli ohms. Work that out, a direct short is capable of delivering maybe 18000 amps. So, imagine blobs of molten copper, burning PVC, exploding controller compents flying in all directiuons, burning anything in close proximity, the back board, the wall, then the house.

I might be being a little melodramatic, but hopefuilly you get the point!

[Halfcrazy]

Yep agreed breakers are a good thing. I have seen to many messes caused with out them. As is pointed out things happen and when and if they do you need over current protection.

[ddxv]

Thanks for the advice, I'll put a breaker in.

[dgd]

Thanks for the advice, I'll put a breaker in.

ok,  but it might be a good idea to look at something like an epanel or MNDC box where you can locate breakers for the battery bank,  Classic and other powered devices plus have a shunt in the negative power line for attaching a WhizBang Jr that can interface to your Classic and provide State of Charge information.

dgd

[ddxv]

Thanks for the advice, I'll put a breaker in.

ok,  but it might be a good idea to look at something like an epanel or MNDC box where you can locate breakers for the battery bank,  Classic and other powered devices plus have a shunt in the negative power line for attaching a WhizBang Jr that can interface to your Classic and provide State of Charge information.

dgd

The Classic is wired into a Magnum ePanel, just no DC+ Breaker yet (bought, shipping).  The WhizBang Jr sounds quite awesome, =)