Reply
 
Thread Tools Search this Thread
 
Old 25 July 2011, 18:16   #21
Member
 
Country: UK - England
Town: Hamble
Length: 9m +
Join Date: Dec 2002
Posts: 2,317
Quote:
Originally Posted by maxhar View Post
. I will be connecting a radio with 7.5amp inline fuse to here, will these distribution fuses cause any problems?

Quote:
Originally Posted by Pikey Dave View Post
If I'm reading the photo right, they're 8A fuses x 4 = 32A max possible load fed, via what looks like a 1.5mm2 length of cheap flex. Corrosion might be the least of his worries.

I'm sure if he's only connecting a radio, 1.5mm will be fine, should be good for 8 or so amps. Would probably best to stick at that though, or get an auto extinguisher.
__________________
It is better to remain silent and be thought a fool, than to speak and remove all doubt!
Dirk Diggler is offline   Reply With Quote
Old 26 July 2011, 09:17   #22
Member
 
Country: UK - England
Town: England
Boat name: n/a
Make: n/a
Length: no boat
Engine: n/a
Join Date: Jul 2009
Posts: 368
The 1.5mm^2 cable is rated at 21 amps. I am connecting a VHF that at most draws 6.3 amps. I don't see a problem.
__________________
rigi36 is offline   Reply With Quote
Old 26 July 2011, 10:13   #23
Member
 
Pikey Dave's Avatar
 
Country: UK - England
Town: South Yorks
Boat name: Black Pig
Make: Ribcraft
Length: 5m +
Engine: DF140a
MMSI: 235111389
Join Date: Feb 2008
Posts: 11,864
RIBase
Quote:
Originally Posted by maxhar
The 1.5mm^2 cable is rated at 21 amps. I am connecting a VHF that at most draws 6.3 amps. I don't see a problem.
That's why you were advised to get professional help the last time you raised this subject, that's me done. Should he require further advice, I refer the honourable gentleman to the signature line below.

ee lad, tha can't educate pork
__________________
Rule#2: Never argue with an idiot. He'll drag you down to his level & then beat you with experience.
Rule#3: Tha' can't educate pork.
Rule#4:Don't feed the troll
Pikey Dave is offline   Reply With Quote
Old 26 July 2011, 10:29   #24
Member
 
Country: UK - England
Town: England
Boat name: n/a
Make: n/a
Length: no boat
Engine: n/a
Join Date: Jul 2009
Posts: 368
Well it was a professional boat builder who put in the 'dodgy' fuse box.
__________________
rigi36 is offline   Reply With Quote
Old 26 July 2011, 10:43   #25
Member
 
Country: UK - England
Town: Hamble
Length: 9m +
Join Date: Dec 2002
Posts: 2,317
Quote:
Originally Posted by maxhar View Post
Well it was a professional boat builder who put in the 'dodgy' fuse box.


Quote:
Originally Posted by maxhar View Post
The marine dealers that installed the outboard put it in, I would have thought they knew what they were doing.

rare to find a "marine dealer" who is also a "professional boat builder"

You've asked for advice, been given it, up to you if you wanna take it
__________________
It is better to remain silent and be thought a fool, than to speak and remove all doubt!
Dirk Diggler is offline   Reply With Quote
Old 26 July 2011, 12:35   #26
Member
 
Country: UK - England
Town: Southampton
Boat name: SMH Rib / War Shot
Make: Ribtec / Scorpion
Length: 4m +
Engine: 100hp Yam/150hp opt
Join Date: Sep 2003
Posts: 2,069
RIBase
"Hella" type fuses.

Used on almost every boat built in the 1970s and 1980s.

Yes, prone to corrosion on the ends of the fuses - but if being used on the non-salty Thames will be fine with regular inspection / cleaning.

Rating indicated by colour and moulded into the plastic body of the fuse (Not ceramic as stated above).

The original question was "will it be ok to connect a VHF with an inline 7.5A fuse to these?"

Answer: Yes
__________________
Searider is offline   Reply With Quote
Old 27 July 2011, 14:44   #27
Member
 
Country: UK - Scotland
Boat name: Wildheart
Make: Humber/Delta Seasafe
Length: 5m +
Engine: Merc 60 Clamshell
MMSI: 235068449
Join Date: Apr 2007
Posts: 4,667
When wiring my panel I looked at one of these (on sale in a Chandler's). Reason I didn't? I couldnt find small enough rated fuses to put in it!

Now have an enclosed (supposedly) watertight minature slot type.
__________________
9D280 is offline   Reply With Quote
Old 27 July 2011, 18:48   #28
Member
 
Erin's Avatar
 
Country: UK - Channel Islands
Town: A large rock
Boat name: La Frette
Make: Osprey Vipermax
Length: 6m +
Engine: 200 Suzzy
Join Date: May 2004
Posts: 2,893
Regardless of whether they are available through Sowester or not, they are pretty low down the quality list for boat use IMV. No matter how dry you think your console is, it is unheated and pretty much unventilated. It will get damp through condensation and that will be enough to cause corossion on the ends. Don't call us for help when your VHF stops working (oh... just realised you won't be able to )

There are countless people that consider themselves professional in the boating community. Just because they call themselves it certainly doesn't mean they are. If they don't understand tinned cable and reliability in electrical work then I would steer clear. Sadly alot of this type of problem is down to ignorance and the remainder down to cutting costs. Listen to Cookee - we can vouch for his experience. Perhaps you will question how professional your fitter is when you understand that 8A is twice the current your average set of nav lights would take.

And finally, there is no such thing as a current rating for a cable unless you know how long it is. The maximum current it will take depends on it's length and also whether it is enclosed, bundled with other cables or open to the air to dissipate heat.

Get yourself a BEP or BlueSea panel which will be made with stainless steel contacts and take modern automotive fuses. You can then fit and forget.
Erin is offline   Reply With Quote
Old 28 July 2011, 10:55   #29
Member
 
Country: UK - England
Town: England
Boat name: n/a
Make: n/a
Length: no boat
Engine: n/a
Join Date: Jul 2009
Posts: 368
Ok, based on the advice here I am going to remove the current block and supply cable and replace with this:

Circuit / Switch Panels, Bep Atc Fuse Holder 6 Way Screw Terminal from EC Smith UK Marine Supplier

and 4mm^2 Tinned cable.

Does this look like a better solution?
__________________
rigi36 is offline   Reply With Quote
Old 28 July 2011, 11:38   #30
Member
 
Jizm's Avatar
 
Country: UK - England
Town: Southampton
Boat name: Hissing Sid
Make: Ross Smith Cobra
Length: 6m +
Engine: 200HP Optimax
MMSI: 235038046
Join Date: Jun 2002
Posts: 3,804
Quote:
Originally Posted by maxhar View Post
Does this look like a better solution?
Yes, better than what you have.
Jizm is offline   Reply With Quote
Old 28 July 2011, 11:40   #31
Member
 
Country: UK - England
Town: Hamble
Length: 9m +
Join Date: Dec 2002
Posts: 2,317
Quote:
Originally Posted by Erin View Post
Regardless of whether they are available through Sowester or not,
They went bust 10 years ago

Quote:
Originally Posted by Erin View Post
And finally, there is no such thing as a current rating for a cable unless you know how long it is. The maximum current it will take depends on it's length and also whether it is enclosed, bundled with other cables or open to the air to dissipate heat.
Erm, I've always consulted this....
Attached Thumbnails
Click image for larger version

Name:	image0-5.jpg
Views:	213
Size:	57.7 KB
ID:	61143  
__________________
It is better to remain silent and be thought a fool, than to speak and remove all doubt!
Dirk Diggler is offline   Reply With Quote
Old 28 July 2011, 12:07   #32
Member
 
Country: UK - England
Town: Hamble
Length: 9m +
Join Date: Dec 2002
Posts: 2,317
There's some very useful info to be found here as well....

http://www.aquafax.co.uk/pdfs/08a_cat.pdf

Interesting how a tinned wire is rated higher than plain multi strand copper.

I try to only use tinned on all my jobs, but find it interesting that most electrical equipment, engine looms etc are nearly always un-tinned multi copper, although they sometimes dip the ends in solder, which to me is wrong. Seen wiring fail from breaking at the soldered end.
__________________
It is better to remain silent and be thought a fool, than to speak and remove all doubt!
Dirk Diggler is offline   Reply With Quote
Old 28 July 2011, 12:14   #33
Member
 
Country: UK - England
Town: England
Boat name: n/a
Make: n/a
Length: no boat
Engine: n/a
Join Date: Jul 2009
Posts: 368
So to be future proof bearing in mind that all will probably ever be running from the new BEP fuse panel will be a nav light, VHF radio and chartplotter what mm^2 (tinned) cable should I be running from the battery to the fuse panel?
__________________
rigi36 is offline   Reply With Quote
Old 28 July 2011, 12:34   #34
Member
 
Erin's Avatar
 
Country: UK - Channel Islands
Town: A large rock
Boat name: La Frette
Make: Osprey Vipermax
Length: 6m +
Engine: 200 Suzzy
Join Date: May 2004
Posts: 2,893
Quote:
Originally Posted by Dirk Diggler View Post
Erm, I've always consulted this....
You obviously understand I2R and hysteresis losses. Perhaps you'd like to give the national grid your check sheet and tell them that they needn't ramp up their distribution voltages to overcome current limit capability of cable over long distances.
Erin is offline   Reply With Quote
Old 28 July 2011, 13:12   #35
Member
 
Crusher's Avatar
 
Country: UK - England
Town: Southampton
Boat name: Bubbas Bouy
Length: 7m +
Engine: Mercruiser
Join Date: Mar 2011
Posts: 629
RIBase
Quote:
Originally Posted by Erin

You obviously understand I2R and hysteresis losses. Perhaps you'd like to give the national grid your check sheet and tell them that they needn't ramp up their distribution voltages to overcome current limit capability of cable over long distances.
Whilst you may very well be technically correct, I think you are completely missing the point. It needs to be fit for purpose, and if you are changing conductor sizes dependent on a 4m rib compared to a 9m rib,and cable installation technique then you are trying to make electrical installations a black art which it is not. I have yet to see a "quality" installation by anyone in the small boats "marine electrical industry" and while I haven't seen them all I have looked at a lot.

Poor guy was just asking for some PRACTICAL advice, next we should start to debate Einsteins theory or relativity...

Sent from my iPhone using Rib.net
__________________
Crusher is offline   Reply With Quote
Old 28 July 2011, 13:18   #36
Member
 
Country: UK - England
Town: England
Boat name: n/a
Make: n/a
Length: no boat
Engine: n/a
Join Date: Jul 2009
Posts: 368
So, what cable to go to the fuse box from the battery?
__________________
rigi36 is offline   Reply With Quote
Old 28 July 2011, 20:55   #37
Member
 
Country: UK - England
Town: Hamble
Length: 9m +
Join Date: Dec 2002
Posts: 2,317
Quote:
Originally Posted by Erin View Post
You obviously understand I2R and hysteresis losses. Perhaps you'd like to give the national grid your check sheet and tell them that they needn't ramp up their distribution voltages to overcome current limit capability of cable over long distances.

Actually, yes, I do, but I think your losing sight of the fact that this is only a little boat.

Dunno what you do for a living but I suspect your a bit of a jobsworth!
__________________
It is better to remain silent and be thought a fool, than to speak and remove all doubt!
Dirk Diggler is offline   Reply With Quote
Old 28 July 2011, 21:03   #38
Member
 
Erin's Avatar
 
Country: UK - Channel Islands
Town: A large rock
Boat name: La Frette
Make: Osprey Vipermax
Length: 6m +
Engine: 200 Suzzy
Join Date: May 2004
Posts: 2,893
Assuming your battery is about 1m away (i.e. total return cable length of 2m) and you want less than 3% voltage drop for your equipment then I would suggest 4mm2 as being suitable. This also assumes that ultimately you will draw no more than 20A off your fuse panel. 3A for nav lights, 3A for GPS and 8A for VHF with an arbitrary 6A capacity left over for future gadgets. If your battery was 3m away you would need 8mm2 cable as 4mm2 woudl only give you 15A before voltage drop becomes an issue.

Quote:
Originally Posted by Dirk Diggler View Post
Dunno what you do for a living but I suspect your a bit of a jobsworth!
Far from it. Nothing riles me more. What does though, is people asking for advice and only being given half the story. More like trying to be a perfectionist rather than a jobsworth.

Quote:
Originally Posted by Crusher View Post
Poor guy was just asking for some PRACTICAL advice,
I did give him practical advice. I told him to get a BEP or Bluesea fusebox. I've also just told him what cable size to use.

Quote:
Originally Posted by Crusher View Post
next we should start to debate Einsteins theory or relativity...
We'll leave that to Gotchiguy I think
Erin is offline   Reply With Quote
Old 29 July 2011, 07:38   #39
Member
 
Country: UK - England
Town: England
Boat name: n/a
Make: n/a
Length: no boat
Engine: n/a
Join Date: Jul 2009
Posts: 368
Thanks Erin. I have ordered 4m of 4mm^2 tinned cable in both red and black as well as a Blue Sea fuse box with negative bus bar.
__________________
rigi36 is offline   Reply With Quote
Old 29 July 2011, 08:15   #40
Member
 
biffer's Avatar
 
Country: UK - England
Town: swanwick/hamble
Boat name: stormchaser
Make: custom rib
Length: 8m +
Engine: inboard/diesel
Join Date: Aug 2007
Posts: 3,848
Well I might as well round it off to 30 posts but you got the best end result in the end. It should be something less to worry about when you've done

Sent from a remote device
__________________
biffer 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




All times are GMT. The time now is 10:12.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.