the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
icon

Fuse Size?


Post ReplyPost New Topic
< Prev Topic Next Topic >
rodney_rude_1 
Member - Posts: 11
Member spacespace
Joined: March 07, 2007
Location: Australia
Posted: March 08, 2007 at 7:20 PM / IP Logged  

Gday Master

the amp (2 channel>bridged) has two dvc subs (300watt rms each) rigged up to a 4ohm load.

still a 150A fuse?

cheers

=success isnt mesured by the depths of your pockets=
master5 
Silver - Posts: 1,123
Silver spacespace
Joined: October 10, 2006
Location: United States
Posted: March 08, 2007 at 7:51 PM / IP Logged  

Well your final load on the amp will be 2ohms when bridged...what is that amp's RMS power rating @ 2ohms? I bet it's pretty darned up there...above 1000w ?

Now using smaller fuses then you need will not hurt anything per say...just become annoying when they keep blowing. Since this thread had established that a 4ga. wire is appropriate to use up to a 150a fuse..that would be the best bet.

If you were using a lower powered amp..lets say 150w RMS....and you happened to be using a 4ga.  then I could see no problem using a smaller fuse like a 60a since there would be no reason for it to blow if everything is properly operating and installed. In other words using a larger wire then is required is not going to force more current into the amp..the amp only uses what it needs.

The things to be most concerned about is...A)  using a wire that is too small (this can cause voltage drop)...and B) using a fuse that is too large for the WIRE...afterall we would rather a fuse blow then burn up the ride.

Well thats the way I see it anyhow.

master5 
Silver - Posts: 1,123
Silver spacespace
Joined: October 10, 2006
Location: United States
Posted: March 08, 2007 at 7:53 PM / IP Logged  
Oh....and cheers to you as well....or how my Sister from Norway does it....."skoal !!!!!"
rodney_rude_1 
Member - Posts: 11
Member spacespace
Joined: March 07, 2007
Location: Australia
Posted: March 08, 2007 at 8:34 PM / IP Logged  

Fuse Size? - Page 3 - Last Post -- posted image.

^^^thats how i've rigged up the subs because the amp is only stable as low as 4ohms when bridged. (1x1600watt RMS)

now i know i should be using 2ga or bigger but 4ga is all that was availiable. i will upgrade to a bigger wire down the track when i install a distribution block to run another amp......or three hehe. i know that the fuse will have to change (later on) as well because of more current the bigger wire will be drawing to power more amps. thats for another time later though.

cheers or 'skoal' lol

=success isnt mesured by the depths of your pockets=
master5 
Silver - Posts: 1,123
Silver spacespace
Joined: October 10, 2006
Location: United States
Posted: March 08, 2007 at 10:18 PM / IP Logged  

Series/parallel..perfect...and you are on the right track with considering the upgrade to a 2ga. in the future.

The only area it seems there is some confusion is when you stated "i know that the fuse will have to change (later on) as well because of more current the bigger wire will be drawing to power more amps"

It is NOT the wire that draws current..it is the device you connect to it..in this case a monster of an amplifier, and more in the future. The wire is simply a vessel for this current flow. If the wire is too small (higher gauge) all those "electrons" that are being called upon to do the work increasing the power..well they simply can't fit..they get choked up...rub up against each other and the wire..and you guessed it...heat (yes a wire too small gets hot) and voltage drop.

Although the following analogy oversimplifies the theory...as well as dealing with the speed of electron flow (quite fast..think light speed)..you can look at it this way......

Think of a tunnel..think of the cars as electrons..or the current..the more cars..the more current. What happens if too many cars try to speed into a small tunnnel all at once????   A crash...a mess..traffic stops flowing...or slows down quite a bit.

Now for the opposite...lets say a wire that is bigger then you actually need.....well if a tunnel was so big that there were never enough cars to slow down the traffic..that would not hurt anything...right? But it is overkill...you would be taking up real estate for a tunnel bigger then required (unless of course you are planning for the future when there is going to be more traffic).

If the wire is bigger then you need..it hurts nothing..has no effect on current flow at all...the current that is needed by the device (amp) will effortlessly flow...unless the fuse (toll booth..lol) is too small for the car...what happens??

Ok I think you get it now...cheers, skoal and salute...aye,lol

rodney_rude_1 
Member - Posts: 11
Member spacespace
Joined: March 07, 2007
Location: Australia
Posted: March 12, 2007 at 1:30 AM / IP Logged  

i now know the physics on current flow etc. good description for a newb like myself...

but on another topic.

-amplifiers. 'RCA output'-

my amplifier has RCA outputs near the input. now. can i hook up another amplifier using those rca output on the amp?

or will i have to get a high level converter for the new amp

obviously ill be getting bigger wire or running a different power cable to run this amp.

it is a 150watt rms x4 stable to 4ohms. not sure of brand but thats the type of amp im looking for.

yes....slightly less power draining than the 1600watt rms model running the subs i have currently got. this other amp is for the 6x9 speakers and components in the car.

wiould the rca outputs on the other amp be able to use to send the signal to the other amplifier?

cheers mate

=success isnt mesured by the depths of your pockets=
dangerdamo 
Member - Posts: 1
Member spacespace
Joined: May 21, 2007
Location: Australia
Posted: May 24, 2007 at 1:19 AM / IP Logged  

Hi All,

Installing a new system in my car, gotta love spending money, and have just got a couple of wiring kits. my plan was to run a 4 guage wire from the batt to a distribution block and then run two 8 guage wires to my amps. Now with my 4 guage wire i got an 80amp fuse and with the two 8 guage i got two 60 amp fuses. Now from what you've said running the fuses would be fine as they will be lower then the capacity of the wires and i would be able to run the two 60amps after the distribution block (thanks DYohn, would have missed that otherwise.) however according to the RMS to Current Draw i will be running more than 80 amps through the main wire and more than 60 amps through one of the 8 guage (2 amps are 4x100RMS and 2x125RMS).

So my questions; will i be blowing up fuses when there is nothing wrong if i install what i've got? should i go and buy a 120-150amp fuse for the main cable and put the 80amp fuse on the 4 channel amp? and are the fuses being packed in these kits significantly less then the wires capacity on purpose to stop people without access to the 12volt killing themselves?

Apologies for the newbie question, i think my bigger fuse method is right but would love to get your advice. have been reading the site for about 2 months now, been fantastc. Bit off topic but doing up a Feroza for some reason and now on the sound part, hoping to take some photos and show off my progress, trying my hand at box building, fiberglassing and lights/presentation thanks to the site.

Cheers,

Danger

Danger Williams
Diahatsu Feroza 1990
Blaupunkt Amp, Splits and 6x9s
Pioneer Amp and Subs
hamzter 
Copper - Posts: 116
Copper spaceThis member has made a donation to the12volt.com. Click here for more info.spacespace
Joined: March 15, 2005
Location: United States
Posted: July 16, 2007 at 3:25 PM / IP Logged  
I just got off the Phone with Eclipse Tech Support and they said that my under rated fuse could cause my system to have a ground loop issue.
Does this sound right to you guru's?
I currently am running 2 x 60a Maxi Fuses for my 2 MTX amps. One is rated 75 amps (3 x 25a) and the other 90 amps(3 x 30a).
thanks.
Mark "Hamzter" Cinense
1991 Infiniti G20 w/JDM SR20DE
Eclipse CD8445
MTX Thunder 684
Polk DB6750
Polk DB6500
Optima Red Top in the Trunk
Page of 3

Sorry, you can NOT post a reply.
This topic is closed.

  Printable version Printable version Post ReplyPost New Topic
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You cannot vote in polls in this forum

  •  
Search the12volt.com
Follow the12volt.com Follow the12volt.com on Facebook
Sunday, January 17, 2021 • Copyright © 1999-2021 the12volt.com, All Rights Reserved Privacy Policy & Use of Cookies
Disclaimer: *All information on this site ( the12volt.com ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.

Secured by Sectigo
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
Support the12volt.com
Top
the12volt.com spacer
the12volt.com spacer