Don’t Assume

[Cheesey69]

So we arrived for our holibobs Saturday afternoon and turned the to absolutely nothing. Dead, nada 

Starter battery was deader than jumbo cords, 1.5 volts. Too late to do anything we decided to wait for Sunday. First of many problems was the battery was a good one AGM flat top, 140 Amp with m8 bolts very big, deep discharge and not what I consider a starter battery. 
Looking around at what was open and what they was selling, decided on Halfords. Got myself a big standard starter battery because that’s all it should be doing right? Noting the round posts I got hold of terminal clamps and bodged on the round terminal ends to the nut. Looked bad but performed ok. Saved the holiday. 
So what drained it? Well a couple of weeks ago I bought a cheap car stereo unit off that well known auction site to replace the standard unit that died. 
It works well, has DAB and usb sockets that can charge phones. 
Straight DIN connections made it a straight swap. Set up so it’s on when engine is off same as other one. 
But those USB are on all the time. 
Draining power from the starter battery. Yup, the radio and I’m hoping not the 12v socket above it, are wired to the starter battery not the domestic bank.

The domestic bank is looked after by mains charger. 
With a bad feeling, I waited until the bilge pump came on and switched off the 12volt cut off switch which stopped the pump. 
I know that’s wrong and it needs to be wired to the starter bank without interruption via a fuse. 
so my future is going to involve lots of bending myself in odd places and bits of wire. 
 

[MargeandParge]

Wait until bending yourself in odd places and bits of wire becomes a daily routine to get dressed .

Kindest Regards Marge and Parge 

Good luck with the electrics as they are never as intended 

 

 

 

[Andrewcook]

I hope you got a very good Lady Wife to sooth your Back after a back breaking sorting out the Wireing job. Good luck on doing it.

[grendel]

This was the prime reason I fitted the little 50W solar panel to water rail, just to keep the starter battery topped up should the boat be unplugged, or the credit run out on its home mooring meter. it also does a good job of keeping that battery topped off when under way and you have the alternator set to charging the domestic bank.

[gancanny]

17 minutes ago, grendel said:

have the alternator set to charging the domestic bank.

i would think most boats are fitted with split chargers these days, but i do agree with the solar panel

[grendel]

Water Rail isnt most boats, so she has an unusual arrangement with a changeover switch.

[Andrewcook]

Gendel how long do Solar panels last and the cost of replacing them. As I agree it does helps the Battery s to a longer life expectancy.

[grendel]

they start degrading as you use them, but some are said to still be producing 80% of the original out put after 25 years, my little 50W panel was £70 for panel, wiring and charge controller- ie everything you needed to make a solar installation.

[grendel]

I got mine from lowenergysupermarket.com, mine are the monocrystaline (better but more expensive type) and are expected to degrade at between 0.5-1% per year and are expected to be above 87% of the original output after 25 years.