The C-Brats Forum Index
HomeForumsMy TopicsCalendarEvent SignupsMemberlistOur C-DorysThe Brat MapPhotos

Fuses at both ends charging cables?

 
Post new topic   Reply to topic    The C-Brats Forum Index -> Electrical and Wiring
View previous topic :: View next topic  
Author Message
Ken O



Joined: 05 Mar 2014
Posts: 94
City/Region: Billings
State or Province: MT
C-Dory Year: 1990
C-Dory Model: 22 Cruiser
Vessel Name: Ravens' Roost
Photos: Ravensí Roost
PostPosted: Fri May 19, 2023 5:22 pm    Post subject: Fuses at both ends charging cables? Reply with quote

I'm upgrading my solar power and adding a DC-DC chargers. The chargers can't fit in the starboard lazarette/battery compartment, so they will go in the cabinet under the stove. This means that I will have 2 hefty cables with batteries at one end and chargers at the other. Current source could be at either end. Would there be any harm in putting fuses at both ends of a cable? We are usually told to put the fuse near the battery, but in this case, I could have 20 amps going the other way, and I don't think a short in the middle would care if there was a fuse at the battery end. Thoughts? Thanks.
_________________
"If it were easy, everyone would be doing it." --Circumnavigator and author Larry Pardey.
Back to top
View user's profile Send private message
WCF



Joined: 21 Feb 2023
Posts: 19
City/Region: Central
State or Province: WA
C-Dory Year: 1995
C-Dory Model: 22 Cruiser
PostPosted: Fri May 19, 2023 7:46 pm    Post subject: Reply with quote

I just went through this with the same sized DC-DC; I also put it in the galley cabinet. It sounds like you are building almost the same system I put together; I had a similar question Smile

The manual for my DC-DC charger specified that ANL fuses were required at each end. I used one ATO at the start battery (Bluesea battery terminal fuse block type) and one ANL and it has been working great. My charger recommended 30 amp fuses at each end, which is acceptable for most ATO type fuse blocks.

You mentioned heavy wire. Double check the wire size you need for a 20 amp charger; the manual for my DC-DC charger, and confirmed by Bluesea's chart put me at 10 gauge, which is a lot easier to work with.

http://assets.bluesea.com/files/resources/newsletter/images/DC_wire_selection_chartlg.jpg
Back to top
View user's profile Send private message
T.R. Bauer



Joined: 17 Nov 2007
Posts: 1683
City/Region: Wasilla
State or Province: AK
C-Dory Year: 1993
C-Dory Model: 22 Cruiser
Vessel Name: C-Whisperer
PostPosted: Fri May 19, 2023 11:50 pm    Post subject: Reply with quote

There are systems that require fuses on the ground side too...Not making that up! Anyway, more the merrier I suppose.
Back to top
View user's profile Send private message Send e-mail
smckean (Tosca)



Joined: 18 Jan 2014
Posts: 955
City/Region: Guemes Island (Anacortes)
State or Province: WA
C-Dory Year: 2005
C-Dory Model: 25 Cruiser
Vessel Name: Tosca
Photos: Tosca
PostPosted: Sun May 21, 2023 1:53 pm    Post subject: Reply with quote

Quote:
I don't think a short in the middle would care if there was a fuse at the battery end.

Exactly! A fuse protects the wire downstream of the fuse. A short before the fuse (i.e., between the source and the fuse) could fry the wire (fire?) between the source and the short since the over current would not need to flow thru the fuse.

I think you're smart to put fuses at both ends to keep wire between source (any source) and the fuse as short as possible.

P.S. WCF is correct. Wire size mostly depends on max amps flow. Those huge cables you see on batteries are for the circuits that will carry 50, 100, or even more amps (volts don't matter except in terms of voltage drop for longer runs).....such things as engine start cables or inverters or battery to major distribution buss.

_________________
Sandy McKean
Purchased Tosca in 2014
Re-powered to Yammi 200 in 2015
Back to top
View user's profile Send private message Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    The C-Brats Forum Index -> Electrical and Wiring All times are GMT - 5 Hours
Page 1 of 1

 
     Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum



Page generation time: 0.0224s (PHP: 63% - SQL: 37%) - SQL queries: 21 - GZIP disabled - Debug on