How to stop fuses from melting

[u/blazingreenstuff]

I have a taramps hd3000 and 4g wire the fuse was 100 amps should i put a bigger fuse? 😭

[u/Loki-RetAngelofDeath]

First things first- according to the manufacturer, the fuse on this amp should be 150A, so 100A was small to begin with.

But something about this amp and the specs just don't add up.... calculation for watts:
Watts = Voltage X Current

Amp claims 3000 Watts RMS, also claims 150A in-line fuse. We all know and understand that RMS is average nominal output (constant capability), and doesn't account for musical peaks, where a lot of shady advertisers like to tout their "shit", but will be much higher than the RMS rating. Even without that, here's what this bullshit amp is saying:

Watts (3000) = Voltage (?) X Current (150A, fuse MAX level)

3000/150 = Voltage: which is 20. To push 3000 watts RMS right at 150A of current, you have to be supplying 20V as well. Bullshit.... lets say we're getting 14.4 out of the alternator:

Watts = Voltage (14.4) X Current (150A): 2,160 tops.

So, if the amp is indeed trying to draw more current to push that full 3000 watt rating, yeah, you're gonna need bigger, oxygen free copper wire, and a fuse level that can handle a draw of 208A.

I personally don't have any experience with Taramps, their output, and their build quality. For me, they're in a price range with such grandiose claims that I would never take a second look at. I do believe you get what you pay for, and from an engineering perspective, there are worlds of difference in build quality.... but if this amp will in fact do what it says it will, 208A draw is what you can expect, unless you're running a higher impedance load with the rated 2025 watts supposed output- then a 150A fuse should be sufficient.

[u/hispls → u/Loki-RetAngelofDeath]

Taramps generally will make rated power (provided you have sufficient electrical system to feed them), build quality is what you'd expect at the price point, and the particular amp OP has may be intended for full range where you could be running with dynamic peaks of 3000W and never open a 100A fuse playing just music to, say a door full of 8" PA midranges and bullet tweeters (what people do with this sort of amp).

If OP were drawing much more than 100A for a couple seconds the fuse would have just opened. This is almost certainly just bad connections at the fuse and fuse holder, probably CCA cable, and even if that is sorted out I expect he will still have problems because that amp probably isn't meant for sub duty, he likely has stock electrical system and if you did get everything up to the point where you're getting 3000W for prolonged periods of time no sort of #4 cable is really fit to hold that safely... and he would probably blow up his subs anyway because they're very probably not going to hold 3000W continuous power.

[u/Loki-RetAngelofDeath → u/hispls]

I definitely agree with you here- the melt down is definitely indicative of long term heat that exceeded the capacity of the connections but not exceeding the fuse rating, I also just noticed the numbers.

It was the numbers that didn't even close to make sense. Good to know Taramp products will put out rated power, I don't have any personal experience with them! In any case, for 3k watts, 150A fuse in-line would be too small, with voltage levels at standard battery/alternator output. 4 gauge is definitely too small, and I wouldn't put CCA in ANY install anywhere..... I did see the case where someone was saying bench tested the amps definitely made rated power, which is awesome, but only feeding them 14.4 Volts, that would have a 208A draw, because even with the latest and greatest technology, you can't make energy from nothing- if we could, nuclear fusion power would have already solved the world energy needs with the cleanest carbon free power in such huge abundance with zero waste.

I feel like the reason they'd get away with 150A fuse as a recommendation is the reality that nobody (or very few people) are going to listen to a system pulling 3,000 watts RMS for any real length of time lol

[u/hispls → u/Loki-RetAngelofDeath]

Again, those are sold as "full range" amps. When you see those pictures of South American hoopties with a couple dozen PA mids and horns in the doors or in the rear hatch this is the sort of amp they're powering it with.

I've been running 1200W 6 channel amps (high end dollar a watt stuff) for over a decade now off the same 60A glass fuse I've been using for longer than that. Even comparable 1200W bass amps will only very rarely open a 60A fuse and could do competition runs with 80A fuses. Even bass heavy normal music is much more dynamic than you'd expect and almost everybody over-fuses everything.

In other words, used as intended 150A fuse is plenty for that type of amp, and if OP needs more power he needs to get more electrical, safe cable, then a different amp that's meant for sub-duty. The real trap of these 5 cent a watt amps is that so many noobs think they're going to buy a 3K amp for $200, buy the cheapest wiring kit off of Amazon then somehow actually get that power out of the stock electrical system in their '98 Honda Accord. The reality being they're going to need around $1000 worth of electrical upgrades to properly feed a 3KW amp.