Reply
 
Thread Tools Search this Thread
 
Old 01 January 2019, 13:15   #1
Member
 
Country: UK - Channel Islands
Town: Jersey
Boat name: Jazcabelle
Make: Ballistic
Length: 7m +
Engine: Petrol 150
Join Date: May 2017
Posts: 245
Mega fuse size

Hi there,

I am installing a new bluesea add a battery kit and as part of that kit I need to install the split charge relay. It’s the 120a version.

I’m installing mega fuse holders in between the relay and batteries, and have 35 and 50mm tinned cable, but I’m not entirely sure in fuse size.

I’m running a yam 150 hpdi and both my batteries are 110amp. The instructions say 80amp for 2awg cable but as my cable is 35 to the electrics and 50mm from the batteries should I go for 150amp?

Any advice would be greatly appreciated.

T.i.a.
__________________

__________________
Chanchan168 is offline   Reply With Quote
Old 01 January 2019, 16:57   #2
Member
 
Country: UK - England
Town: Waterlooville
Boat name: Tickler
Make: Halmatic P22
Length: 6m +
Engine: Inboard Diesel 140HP
MMSI: 235115642
Join Date: Sep 2015
Posts: 515
RIBase
The cables to the relay are based on the charging rate of the alternator. I'm not sure which ACR you have but in the instructions it talks about the charging amps. I imagine your alternator is only kicking out 25A or so. As a result 10mm cable will be OK.

The ACR isn't meant to carry any starting loads - it's just there to manage the charging of the two batteries. It's no issue to use bigger cable though. The fuse is really to protect the cable so you could go for a bigger fuse. 35mm cable has a rating of 240A so a 150A fuse would be more than fine.
__________________

__________________
GuyC is offline   Reply With Quote
Old 01 January 2019, 17:12   #3
Member
 
Country: UK - Channel Islands
Town: Jersey
Boat name: Jazcabelle
Make: Ballistic
Length: 7m +
Engine: Petrol 150
Join Date: May 2017
Posts: 245
Thanks Guy, makes sense. The Acr comes in the kit with the battery isolator from Bluesea.

The diagram just shows a mega fuse link between the Acr and both batteries. In the pic it shows 80amp with 2awg cable and then a 150amp fuse between the isolator and the main fuse block.

Iíve attached a pic.

Thanks again
__________________
Chanchan168 is offline   Reply With Quote
Old 01 January 2019, 17:13   #4
Member
 
Country: UK - Channel Islands
Town: Jersey
Boat name: Jazcabelle
Make: Ballistic
Length: 7m +
Engine: Petrol 150
Join Date: May 2017
Posts: 245
Hereís a picClick image for larger version

Name:	IMG_1154.JPG
Views:	93
Size:	185.8 KB
ID:	128108
__________________
Chanchan168 is offline   Reply With Quote
Old 02 January 2019, 01:18   #5
Member
 
Country: UK - England
Town: Waterlooville
Boat name: Tickler
Make: Halmatic P22
Length: 6m +
Engine: Inboard Diesel 140HP
MMSI: 235115642
Join Date: Sep 2015
Posts: 515
RIBase
The two lower fuses in the picture are related to the charging and can be sized either on the charging rate of the alternator or the size of the cable you've used. If you've used 35mm cable between the ACR and the house and starter batteries, then either a 75A or a 150A will be fine.

For the main fuse block, it's dependent on the cable size which in turn is dependent on the electrical load from the consumers. I'm guessing that the consumer load won't be more than about 20A - VHF, chartplotter, bilge pump etc. As a result you can get away with quite a small wire feeding the fuse block - 6mm with a 40A fuse for example. It is all dependent on what you are running.
__________________
GuyC is offline   Reply With Quote
Old 02 January 2019, 05:19   #6
Member
 
Country: UK - Channel Islands
Town: Jersey
Boat name: Jazcabelle
Make: Ballistic
Length: 7m +
Engine: Petrol 150
Join Date: May 2017
Posts: 245
Cheers Guy, thanks
__________________
Chanchan168 is offline   Reply With Quote
Old 02 January 2019, 12:33   #7
Member
 
Country: UK - Scotland
Town: denny
Boat name: breezy
Make: northcraft
Length: 6m +
Engine: honda 150
Join Date: May 2016
Posts: 792
RIBase
ive got the same set up and the 2 fuses at the charge relay are 80amp and the one feeding the aux electrics is a 40amp
__________________
breezeblock is offline   Reply With Quote
Old 03 January 2019, 03:01   #8
Member
 
Country: UK - Channel Islands
Town: Jersey
Boat name: Jazcabelle
Make: Ballistic
Length: 7m +
Engine: Petrol 150
Join Date: May 2017
Posts: 245
Brilliant thanks.
__________________
Chanchan168 is offline   Reply With Quote
Old 12 January 2019, 13:19   #9
Member
 
Country: UK - Channel Islands
Town: Jersey
Boat name: Jazcabelle
Make: Ballistic
Length: 7m +
Engine: Petrol 150
Join Date: May 2017
Posts: 245
Quote:
Originally Posted by breezeblock View Post
ive got the same set up and the 2 fuses at the charge relay are 80amp and the one feeding the aux electrics is a 40amp
Hi Breezeblock,

What size cable have you run from the batts to the relay?

Would 25mm or 4awg be ok with an 80amp fuse?

T.i.a.
__________________
Chanchan168 is offline   Reply With Quote
Old 12 January 2019, 13:43   #10
Member
 
Country: UK - Scotland
Town: denny
Boat name: breezy
Make: northcraft
Length: 6m +
Engine: honda 150
Join Date: May 2016
Posts: 792
RIBase
big enough I can't remember what size it was just a short bit that was underneath the bench
__________________

__________________
breezeblock is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 09:28.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.