Battery SOC query

[Martin Megson]

 

For something ready made this 200A bus bar may do OK:

 

 

http://www.12voltplanet.co.uk/4-point-negative-distribution-block-busbar.html

 

Best have the high current paths on same or adjacent studs. Examples being engine return to starter batt return, inverter return to shunt return.

 

If there's access to tools, they're not too hard to DIY from copper bar, maybe worth starting a new topic with details and photos for ideas.

 

cheers, Pete.

~smpt~

 

Thanks Pete. That looks ideal and a lot cheaper than Midland Chandlers who are charging £50 for a similar item.

[ditchcrawler]

 

Thanks Pete. That looks ideal and a lot cheaper than Midland Chandlers who are charging £50 for a similar item.

There are a selection here some with covers http://www.asap-supplies.com/search/busbar

[Detling]

200A bus bar not sure it will be strong enough. The Inverter on full chat can pull nearly 300A and the engine starter crank current will probably exceed 500A. Just a though.

[Arthur Brown]

If/when you install a buss bar please be certain that NO steel washers are in the fitup. They get hot and offer high resistance to current.

[smileypete]

Looking at some references, seems the main thing is to use spring washers to cope with differential expansion:

 

http://ecmweb.com/content/belleville-blues

 

I think you'd struggle to find spring washers that aren't made of steel! Perhaps the fit up you experienced did not have spring washers.

 

As mentioned in post #49, if the terminals are matched up in an intelligent way the highest currents will go direct from terminal to terminal in most cases instead of thru the bar.

 

Maybe Meggers can test it with the inverter on full chat for half an hour and confirm whether it's OK.

 

cheers, Pete.

~smpt~

Edited September 1, 2014 by smileypete

[Martin Megson]

Thanks for the advice re potential max current and connection types. My inverter is 2kw and specifies a 70mm cable and a 240 amp fuse. Clearly this and the engine block -ve (which covers the starter motor and alternator) will carry the heaviest current. As Pete suggests I plan to connect these two directly to the shunt and then connect the battery charger (40 amp) and -ve from the domestic circuit through the busbar. I'll run the inverter under heavy load and check nothing is getting overheated.

 

Thanks for the helpful advice. I'm reasonably competent at DIY, all part of owning a boat, but get a bit nervous when dealing with high amperage.

[Martin Megson]

Just a quick thank you for all the advice.

 

I have now got the meter installed and correctly wired up. All seems to be reading as I expected and none of the cables is getting warm so I'm happy they are up to the job. Acid test will come next month when the BSS is due.

Edited September 6, 2014 by Meggers