Hi all absolute beginner I’ve had a Fogstar 300ah fitted a long with a victron 1200 inverter but every time I put the microwave on for two minutes the red terminal gets so hot it’s melting the fuse any ideas very welcome not sure of uprating the wire and fuse
Is the DC cable prefabricated or did you do the crimp yourself?
If so, are you sure the crimp is done OK and the lug is a proper brand/material?
Indeed also for me it looks like the crimp could be the source of heat… The Fuse seem not to be that much damaged especially the bottom of the fuse seem to be uneffected…
How big is the current when you turn on the system
The guy that fitted my frogstar battery is one of their authorised fitters been doing it for years so he made up the lead himself. I’ve just messaged him and he’s said the cable and fuse need to be upgraded any ideas where I can get one made up and the size of lead and fuse? Maybe get one posted to me?
I see a lot of wire’s, it’s a mess.
Where do you live? Prefabricated cables with lugs in almost any size are available.
Looks like a faulty crimping (btw what is the cable size?) in connection with a thin lead!
Ask a local sparky to make one with proper equipment (here in Germany i bought a Klauke system with DIN Leads and the DIN prong (6-120 sqmm), your leads look like normal leads without normation)
That seems like a big ask from a 1200VA (960W) inverter.
@Blowey do not forget that if your microwave says it is 800W, it will draw around 50% more input due to efficiency conversion losses. So 1200W which matches with your Fogstar BMS data. This is a follow on the the post above noting that you ate pushing the inverter.
Most Victron manuals recommend the cable sizes and fuses required. Look on this page to find your model, the manual can be found under downloads.
UK narrowboat by any chance.
Worth noting too that the fuse and holder on the battery are knockoffs of a Bussmann MRBF fuse and holder, so when redoing the system I’d advise spending just a little extra and get genuine products there.
Knockoff:
Genuine fuse:
Genuine holder:
The knockoffs tend to look very similar, but performance is a shot in the dark.
Have you got a link for when I can get these from and I think definitely needs to be 300am, what size cable have you any ideas or links where I can get both made up? Thanks for your reply
I don’t know where you are, so I can’t say what links or cable mfgrs might work for you; powerwerx.com is a great source for getting custom-made cables if you’re in the US, I don’t know if they ship elsewhere.
The fuses and holders are available from lots of sites like Waytek, Mouser, PowerWerx again, and etc; you can also find them under the Blue Sea brand, since Blue Sea buys them and puts them into a retail case and resells them.
Either way, no matter where you are, a good internet search will get you results (as long as you’re not using Google’s AI search).
I’m in Leicester England
Have a look in Halfords. They used to sell a range of premade 50mm2 cables at reasonable prices, although I can only see 16mm2 cable on the website now.
The 16mm2 would do at a push for short lengths as it should handle around 110A at 12V. As stated by others, don’t compromise on quality of connecters, fuses etc and buy original equipment only.
Are those number of times a certain error popped up? If so, then 883 times overvoltage is also a bit concerning. What are your charge settings?
I believe it’d be a very good idea if you get a capable person to check this system end-to-end.
The bad crimp and knock-off fuses/holders is worrying and unnecessary, but improperly set charge parameters means someone with insufficient knowledge or interest set this system up.
This is a matter of your (and other people’s) safety.