DiyMobileAudio.com Car Stereo Forum banner
1 - 8 of 8 Posts

Registered
Joined
210 Posts
Probably have to agree to disagree on this one. Your car, do as you please...

You are probably electrical guy because i can see how fast you moved out from this. First one doesn't understand "electrical code" and another can't read so he choses to wave around with emma rules馃ぃ.

Both of them didn't read part where you imply that fuse protects wire but its specification is chosen by the system.

So its 10 times safer to have 100A fuse on that "80A" amplifier cable than 140A.

Speaking of home, you would have cable that is rated to consumption following by fuse(first guy mentioned it but still culdn't see his miss.) While in car audio you have excessive selection of power cables which doesn't follow load so fuse shouldn't be chosen by the wire rating.
 

Registered
Joined
210 Posts
Try to understand what Slave and I reply than read those rules you copy-paste, at some point you will understand what we talking about.
IF WIRE IS CHOSEN BY THE LOAD, THAN THOSE RULES APPLIES, IF THE WIRE IS EXCESSIVE FOR THE LOAD (this case and most of the time in car audio) THAN IT SAFER TO TAKE LOWER SPEC OF FUSE.

Your car and do whatever you want with it but don't share knowledge you actualy don't understand. Half of the forum have non normed power wiring-> "audio wires" so from the star you can't say "4awg is rated to 140A"... Unfortunately you can't come to my work place so i can show you how real 150A 12V DC wire looks like, feels like and its certificated datasheet.


End of story.
 

Registered
Joined
210 Posts
I think we can all agree that overcurrent devices are meant to protect wire. I think we can all also agree that, to the extent efficiency and equipment performance involve wiring sized to minimize voltage drop, overcurrent devices sized to the load simply make good sense.
^This all the way
 

Registered
Joined
210 Posts
I like solder in copper lugs. I wonder if there is a video comparing crimping vs solder
If you have some money, buy a hydraulic crimper, otherwise DIY hexagon by welding nuts together and cut it in half; proceed to crimp with vise.

Soldering vs crimping can not be distinguished with few words or by a thread on the forum.
This is something that is described by multiple IPC standards and certfications. It is very extensive literature and requires ton of trainings for aquiring each of single certification for it.

Very superficially said; soldering is used where conditions doesn't alow you for crimp (PCB,XT60,RCA).

I also in the past had soldered and taped connections. Even today i do shady things for emergency purposes. But i wouldn't recomend that to anyone, especialy when we talk about simple DC/AC systems like a car audio.
 

Registered
Joined
210 Posts
What happens when the wire size is undersized and cannot pass the amount of current that the amplifier can safely take? That's why you fuse for the wire, not the amplifier.
This is the dumbest comparison, generalisation and statement i've heard in a while!
By totaly different scenario you chose what to do in another. Maybe someone is going to read this and think he is safe to install a system with underated wire if he fuse it by the wire rating.
This is just plain wrong thinking and installation! @ItsonlyaHONDA is good example trying to run 400A throught 0AWG wire.

Overrated wire gives you better voltage drop index which most people in car audio are hunting for.
Here we are speaking about 80A fused amp and non classified 4Awg wire. For starters lets believe that this wire is able to push 140A. Did any of you actualy take in to the account how long is the wire or does it go through the engine(heat). If you actualy insert this into the ISO or ABYC calculator you would see how current drops. One more thing wire current rating is max rating and fuse needs to be at least 20% ->this actual electrical rule.
 

Registered
Joined
210 Posts
See post #35.

Plenty of people don't know any better, and others just use what they have. If they only have 8awg, and they fuse to the wire, they won't set their car on fire, even if the amplifier is capable of much more power than 8awg can support.

Not sure how you read my post and thought I was advocating for undersized wire.
It should be said to that person to upgrade wire at least to the load or more and chose fuse accordingly! I agree about the fire but this approach with the fuse is wrong.
I don't separate the fact that fuse is chosen by the wire raiting if its chosen according to load not under or excessive above.
 

Registered
Joined
210 Posts
I understand all that and your missing my point. I'm not using some cheap 4k amp from Amazon. Its an MMATS, and they are known for good quality amps. Why would they only have 1 0 gauge input and suggest a 400A fuse is what I was wondering. It's a Full bridge amp which I think pull less current as long as I'm not burping test tones full tilt at 1ohm. And most of the time I don't run my system full power cuz it gets loud AF when I'm running at 1ohm. Matter of fact I'll be running this with a D4 Brahma X at 2ohms so I know I'm not going to melt anything.
That terminal is short and by that can handle the current. That same cut sized cable with lenght of 9ft(usual lenght from engine to trunk) woulld fall somewhere in 200-250A if i remember correctly. From your posts i believe you are SPL guy so you probably run short lenght cable or as you said you don't have plan to run that much power. Also you can always buy upsize adapter for the terminal for bigger wire.
 
1 - 8 of 8 Posts
Top