# What gauge power cable and type fuse d I need for an Eclipse EA4100



## movingzachb (Dec 13, 2013)

*What gauge power cable and fuse type to properly run an Eclipse EA4100*

I will be installing this amp in my '99 miata. Front stage is two MB Quart PCE 216 6.5" 130 Watt Max power handling - yet I have the tweeters and woofers wired individually to use a channel for each. I also have two speakers in the rear deck that are MB Quart 6.5 RCE's (not hooked up as I may change them out for bass speakers). But thought about using all four channels for the front stage if it isn't too much.

Eclipse EA4100 400W Max, 4-Channel Amplifier - Sonic Electronix

What gauge wire do I need and what fused size should I use for this amp? I don't know if I am able to find the manual for it online but I want to buy the proper cabling needed for it. Preferably a fuse holder like the ones Phoenix Gold used to make (if they are same quality).


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## DDfusion (Apr 23, 2015)

500 watts or less. 8awg OFC. 8awg can go to 50a


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## Justin Zazzi (May 28, 2012)

Yep, good advice. 8ga wire will make your installation easy since it can bend so much.

Just do your best to make the power cable some reasonable (short) length. If it needs to be something like 15 feet long for whatever reason, you might consider using 4ga wire to keep the voltage drop from getting too high (still fused at 50a since you don't need more than that).

One added benefit of a 4ga wire is adding another amplifier in the future will be easier since you can split it using a distribution block instead of running another piece of wire all the way from the battery.


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## movingzachb (Dec 13, 2013)

With say a 6 gauge wire could you connect a second amp or does it have to be a 4? Just curious (Say if the amps were both 400 watt max).


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## gijoe (Mar 25, 2008)

I'm sure 6awg would be fine. Search "wire gauge chart" then go to images and find a chart that tells you what you need. Look for one that also includes the length of the run, this is important, and seeing as you are driving a Miata, the run might be pretty short, making smaller wire safer.


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## Justin Zazzi (May 28, 2012)

movingzachb said:


> With say a 6 gauge wire could you connect a second amp or does it have to be a 4? Just curious (Say if the amps were both 400 watt max).


Assuming you want to keep using class A/B amplifiers, they are somewhere around 50% efficient meaning you need to supply with twice as much power as they will deliver to the speakers. So if you have two 400w amps, that means you need up to 1600w of power from the battery. A little math with Ohm's Law gives us roughly 120 amps of current at about 13.8v.

As shown earlier, an 8ga wire can safely carry somewhere around 50-60a. So you'll need to use something larger. 6ga can carry about 80-90, and 4ga tops out near 125a (which matches your power demand nicely).

The other thing to consider is voltage drop over the length of the cable. For short distances of up to 6 feet or so, 4ga will be just fine. For longer runs approaching 15 feet, you'll want to increase the power wire size to 2ga or 0ga. This isn't because you need more current capacity and therefore you don't want to use a bigger fuse either. It's because the lower resistance of the thicker cable will give your amplifiers a voltage that is closer to the output of the alternator/battery.


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