my first powercut in 9 years

[book_woorm]

If there is no AC load on the inverter then the only current it will draw from the battery on connection/disconnection will be its background keep-alive for the control system. I very much doubt it would spark. It indicates a fault somewhere. You don't get much of one when you change a car battery. Did you have the DC isolator between the battery and the inverter open or closed when you got the spark? If it was open there should not have been a spark at all!!

Have you checked for a semi short across the DC circuit? even a few hundred ohms will discharge the battery pretty swiftly, I once had a problem of a damp spiders nest inside the battery isolator on a boat! This sort of short works both ways and cuts down the output voltage/current from the battery to the inverter and also from the charger to the battery.

How old is your battery anyway/ how many cycles has it done? Battery systems are not 'fit and forget' they need TLC, keeping clean, debris/infestation free, ventilated, acid vapour free and dry. Have you checked all those points regularly? You might just have more than one fault.

As for camillitech's spark, get a good DC switch they have arc quenching built in to them. Engineers tend to accept risks and bad practice occasionally in things that are part of our everyday life, but don't do it. Prolonged sparking is not good for battery life. It cause multiple inrush currents in a short space of time, hence heat. You end up with distorted plates and the paste separating from the plate.

[camillitech]

If there is no AC load on the inverter then the only current it will draw from the battery on connection/disconnection will be its background keep-alive for the control system. I very much doubt it would spark. It indicates a fault somewhere. You don't get much of one when you change a car battery. Did you have the DC isolator between the battery and the inverter open or closed when you got the spark? If it was open there should not have been a spark at all!!

Have you checked for a semi short across the DC circuit? even a few hundred ohms will discharge the battery pretty swiftly, I once had a problem of a damp spiders nest inside the battery isolator on a boat! This sort of short works both ways and cuts down the output voltage/current from the battery to the inverter and also from the charger to the battery.

How old is your battery anyway/ how many cycles has it done? Battery systems are not 'fit and forget' they need TLC, keeping clean, debris/infestation free, ventilated, acid vapour free and dry. Have you checked all those points regularly? You might just have more than one fault.

As for camillitech's spark, get a good DC switch they have arc quenching built in to them. Engineers tend to accept risks and bad practice occasionally in things that are part of our everyday life, but don't do it. Prolonged sparking is not good for battery life. It cause multiple inrush currents in a short space of time, hence heat. You end up with distorted plates and the paste separating from the plate.

Hi BW, I can assure you that ALL decent sized 'off grid' inverters give a great BIG blue flash when you connect them as they charge the capacitors, at least SMA, Studer, Outback, Trace, Victron and Voltacon do. Yes, I accept and unreservedly agree that it's bad practice   and I WILL fit a proper switch (eventually) In fact, I already have one lined up, a great big 400A 900V ABB motorized one with a manual over ride but but I'll not get that until dry dock next month  

Cheers, Paul

 

[biff]

Hi Billi,
       configuring to 12 volt for testing purposes should be fine. Just put the volt meter on each of your 12v strings and maybe you will spot a dodgy cell.
   However, i don,t think it is your battery bank. All the starting and stopping of the generator was because the charging side of the Victron was not working properly
   and the battery was basically recovering on its own until it died.
     If you had a little time, You could disconnect a couple of 35vmp panels from your array and stick them directly onto the 48v pack
     Leave them for 4 hours or so in decent sunlight. Then try and source an inverter. Do try and avoid 12 volt because you lose so much in the transmission.
  I use a big 20amp scissor type throw switch to disconnect the bank. No sparks at all. However any fooling around the bank rewards me with nasty crackle.
   The 20amp throw switch has replaceable wire fuse and spare fuse when needed. I have never needed the spare fuse in all the years i have been using this system.
   I will have a rootle around the shed and see if I can find a 24volt inverter, I know i have an 800watt x 24volt ups somewhere and a small modified 300watt one as well.
   Something like this would keep you going until you get it all sorted.
   I have a 2.5kw x 48v ups which runs fine, bit juicy but OK in summer when we have excess PV.
   Opppps i also have a few 12volt x 1500watt inverters. (cheap poo)
   Hopefully you will get it sorted before that.
                                          Biff
 Don,t worry Billi, Forklift cells are hard to kill,They are extremely forgiving as well. A good boost directly from the PV should bring them back up to spec.

[camillitech]

Hi Billi,

if you have a bad cell/connection it may possibly have damaged one of your inverters by stressing it. However I'd still steer well clear of 12V unless you do have a bad failed or shorted cell. With good and cleaned connections I fail to see how you can damage your good inverter and at 12V you will have then lost all your PV via the MPPT charge controllers. You really do not want to be rewiring your PV to 12V and the Amperage of your FM 60 and 80 combined is only going to give you 2kW of PV  But I'm sure you've already thought of that.

Good luck, Paul

[billi]

... i guess i did one mistake   years back  , and disconnected a few  aquamatic  filling pipes  from the battery caps  , as Scruff said that is not good that the gases  are directed towards battery poles ....

hi BW , battery is from 2003 ,  so thirteen years old ,  no idea of cycles ... , but i have not given her up yet , still  easy on her to deliver  50% discharge  or about 18 kWh without  getting below 24 volt

I guess i  should have been a bit more carefull last year , when i found  the warm+ cable , when washing machine and dishwasher were on ...

Thanks Paul and Biff , i try to avoid  rewiring the bank to 12 volt  .... guess my day will be cleaning all those poles and testing battery cells...

 

[camillitech]

I'm sure a good cleaning will go a long way to sorting your woes Billi, pretty sure your cells will be OK. They will after all have been getting some charge, probably just 'collapsing' at the higher currents, which I think is what may have made the inverter poorly. It's probably been stuck in 'bulk' for too long being unable to raise the overall bank voltage due to poor connections.

Good luck, Paul

[camillitech]

I guess i  should have been a bit more carefull last year , when i found  the warm+ cable , when washing machine and dishwasher were on ...



 

 

[billi]

i can cry laptopcharger just fried ,  guess something wrong with the waterturbine dumpcontrol....

[Scruff]

I already have one lined up, a great big 400A 900V ABB motorized one with a manual over ride but but I'll not get that until dry dock next month  

Hi Paul,

I have a bag of these. 180A continuous per.
http://www.ebay.co.uk/itm/MERLIN-SOLENOID-CONTRACTOR-VOLTAGE-12-HEAVY-DUTY-/231985938320?hash=item3603707f90
latching type (reversible coil no continuous coil consumption). Parallel them up for more duty you can wire them so one button rules them all. You can set them up as an emergency remote disconnect too.

http://www.albrightinternational.com/products/sw180/

+1 on inverter sparks. I use my bus bars as sacrificial contactors....chunks fly off every time I connect my inverter if the capacitors are discharged.



Terrible news Billi, the laptop PSU is an odd one they have a very wide input acceptance.

[camillitech]

I already have one lined up, a great big 400A 900V ABB motorized one with a manual over ride but but I'll not get that until dry dock next month  

Hi Paul,

I have a bag of these. 180A continuous per.
http://www.ebay.co.uk/itm/MERLIN-SOLENOID-CONTRACTOR-VOLTAGE-12-HEAVY-DUTY-/231985938320?hash=item3603707f90
latching type (reversible coil no continuous coil consumption). Parallel them up for more duty you can wire them so one button rules them all. You can set them up as an emergency remote disconnect too.

http://www.albrightinternational.com/products/sw180/

+1 on inverter sparks. I use my bus bars as sacrificial contactors....chunks fly off every time I connect my inverter if the capacitors are discharged.



Terrible news Billi, the laptop PSU is an odd one they have a very wide input acceptance.

    

How stupid am I, I've got four of those and more in 12 and 24V from winch solenoids!!! I've had a selection for years too 

Still, I'm going to wait for these,



we're changing three this year at dry dock as they're part of a 'critical system' so changed regardless of condition at two years of age.

Cheers, Paul

[Scruff]

Cwaor you always have the best switchgear porn Paul. I best have a lie down. 

[camillitech]

Cwaor you always have the best switchgear porn Paul. I best have a lie down. 

Morning Scruff, would you like one, should be one spare, I only have use for two and there will be more available in the future.

Cheers, Paul

[billi]

.... messuered the acid levle of each cell  ,  they all look like very even charged  and that thingy (forgot the name )  was showing about 1250 on all cells  batt bank with no charge at about 25.2 Volt  , no spark  when i reconnected  the + and -  , Cleaned batt poles ,    and now switched on the 4 kw PV  and charging nicely ....
 , but no inverter connected yet

Got a new laptop charger and have to thing about my AC waterturbine , that fryed the other charger ,  i guess the dump load at the waterturbine must have a fault .... so leave her out of the systhem for now  until i find out , that the regulating  diversion /imersion  at the turbine is  working ,   but think there lies the/a problem , cause it made my laptop charger fry  ,  usually the immersion on those turbines take away all surplus electricity , but id did not  , cause battery was not connected that was too much for my laptop charger  (i guess you all think i talk chineese now  )



Wired the 350 Euro  best generator ever  ( strange enough)  direct into the main distribution board last afternoon , so my son could enjoy some light and computer/TV  last night .... , not sure if i connect the healthy victron today , i still think and try to recall all the details of my systhem  that worked flawless and enjoyable the last couple of years  one then gets a bit too laid back ....  i still would like to try a elcheapo inverter first  ....  maybe i  get one of those taiwan  inverter with PV chargers

Anyway , a more promising day today ....

CU
Billi

[camillitech]

Hi Billi, methinks there's probably nothing wrong with your turbine regulation, probably just the switch mode on the supply confused it or was just too small a load. Methinks that if you'd had a few resistive loads running like incandescent lamps, it would have been just fine.

Good luck, Paul

 

[billi]

ok  good thinking , may have been a too small load   , anyway have to  visit the turbine ......