Any suggestions as to why my new car audio amp keeps blowing fuses?

Question

I have just bought a brand new Infinity 611a Mono amp - this is 456 watts - which the manual informes me that it draws
69A (when i use it at maximum power) - i am using 8AWG cable from the battery ( +ve ) and i created a ground point in the boot which the -ve connects to, i know this circuit works. except as soon as i put in a 60A fuse into the fuse holder by the car battery it blows, and if it doesnt it blows the fuses directly in the amp itself, i have checked the cable (+ve) and i cant find any breaks or shorts! Why is it blowing every fuse i put in???

Answer 1

Does is only blow the fuse when you have the amp turned all the way up, or does it blow the fuse all the time?

One of the first things you should check is to see is whether you have the power hooked up correctly, because it's easy to get the polarity wrong and not know it. My neighbor did because he bought equpment second hand someplace and didn't have any instructions, so he didn't have a clue what he was doing and he just used the trial and error method to hook his up. It was scarry watching him do his car.

If it's blowing a fuse all the time, then either you have a short somewhere or your have a bad amp. All it takes is one stray wire of stranded wire to create a short, so check the wires for your speakers to make sure you don't have any shorts there either.

If it's blowing the fuse only when you turn the amp all the way up, then it could be that it's just protecting itself or there might be a problem with your load. In other words, check to make sure you have your speakers hooked up correctly so that you have the correct amount of resistances (ohms) and wattage ratings.

Answer 2

First of all, let me answer your question with a question. Why is a fuse blowing up in a circuit? Two answers: 1- short circuit. Meaning, Resistance of the load is almost closed to zero or call it Continuity Resistance or in other words your Amplifier or whatever the device maybe is being by-passed by a short circuit connection via the Positive terminal of the battery and its Negative / ground terminal.. Check your connections and Wrong polarity can also cause fuse to blow off. The Current or Voltage is not reaching through your Amplifier and thereby you can not make your Amp work. Check your output connections too. i.e. speaker terminals/ wires there may be short circuit within.

2 - Too much Load. If your device has a potential of drawing large amount of current to produce big amount of power while your source of Current (ie. the battery) has lower aperage than your device then fuse will certainly blow. Fuse is like a hose of water or Air.. If your hose can not support the pressure of compressed air or the pressure of water that hose will certainly explode. Check Check and double check your connections... Measure the Resistance between your positive and negative terminals of your Aplifier... and finally try this simple diagnostic solution: Get a high wattage 12 volt bulb (like a head lamp or brake lamp) connect it to series with your device making work like a fuse then if that bulb lights up like as if it has been connected directly to the battery and then see if the Amplier works and if not you have a bad Amp or shorted Amplifier Circuit.

Answer 3

All I can tell you is that the fuses on the amp are intended to protect the equipment from drawing too much current through the speaker load - this will happen IF you turn the volume up - that is exactly what the fuses are there for. Usually if the load is intended to be 2ohm that should not be a problem - but most car audio is 4-8ohm - low loads like 2ohm are likely to draw more current and all amps will at top volume - so the chance of the fuse blowing at high volumes is high in the first place - as to whether anything else is going on I dunno.

Answer 4

the main thing is to put a higher fuse 70-80a, if it still goes thicker whire. i use 20sq wire prob the best you can get.. i dont use a fuse because of the thickness of the wire.. im running two 750w Subs and Two 360W 4 way Speakers, Hasent Gone for me at full power using 760w amp.
Battery Cabe isnt up to the job!!!

Answer 5

might be a faulty amp or wiring easiest thing to do is swap the amp for a new one where you bought it and then if it is still doing the same look into uprating the wires

Answer 6

replace the fuse with a nail dude party on

Answer 7

either the amp isnt powerful enough or you've got a bad earth :D

Answer 8

Have you checked that the polarity right?

Answer 9

you play the wrong type of music!!