Fuse Size - - Help?
I am going to be installing a Stinger SHD201 HPM ANL inline fuse holder and need to know what size to get as far as the fuse goes. My options are 60, 80 100, 125, 150, 200, 250, 300 amps.
This is for 1/0 HPM stinger power wire with 4 foot run between the battery switch and dist block to the amps.
The 3 amps are Arc Audio KS (300.2, 400.4. 500.1) In total per the spec the output of the amps is 1700.
The cumulative total of fuses in all three amps is 240. (8) 30 amps fuses
What size fuse do I run to keep my 1/0 cable safe?
I'm anti fuses on boat stereo's.....get a circuit breaker if you can, much easier and way more practical.
Nothin worse than blowin a 100 amp fuse then having no stereo the rest of the day....... ( 9/10 times the fuses blow b/c of low voltage--as voltage drops current pulled increases.)
X2 on the breaker.
The 250A or the 300A will be fine.
The one thing I have a concern about is powering the amp off one of the battery switch posts. This is not a good idea for a couple of reasons, but the most important is the fact that the cable running from the battery to that post was not intended to carry the additional 240A load you are about to place on it. Do yourself a favor, and run the amps' power and ground directly to the battery you want to draw from. $.02
Now, if this requires a longer run of wire, then you may need to go up to 2/0 ga cable or pull one amp off and power it separately in order to keep the current draw within the limits of 1/0.
My run from batteries to amp is less than 4 feet with 1/0 cable.
On average the Arc Audio KS amps are 81% efficient at 4 ohms and 76% efficient at 2 ohms.
Based on a correct calculations firguring in efficiency, my 300.4 is pulling 40 amps, my 300.2 is pulling around 65 amps and my 500.1 is pulling 55 amps. Keep in my that these numbers are based on 13.3 volts and respective efficency numbers listed above. So in total I am pulling 160 amps, even if you drop to 12 volts it is no where near the 240 you refrenced earlier.
In years past I have run a 150 amps circuit breaker between the batteries and all three amps, never once tripped it. I think if I was pulling 240 amps, that it would trip at least once???
Anyways, I will go with a circuit breaker.
Ok, lets clarify. It very common to fuse based on the amp's potential current draw, which is exactly what the amp manufacturer did. You gave us that potential draw by stating the 3 amps had 8 30A fuses between them for a total of 240A's. So it's perfectly acceptable to fuse up to that potential (max) current draw. Fusing based on efficiency and current draw at normal listen levels is on the conservative side of safe, and may lead to tripped breakers or blown fuses if the system is pushed hard. $.02
Sounds like you got it under control and already knew the answer, so by all means, proceed with the fuse that you feel comfortable with.
The fusing at the battery only serves to protect the boat from the large cable in the event of an accident. Its possible something would catch on fire before the one gauge cable burns through. All amplifiers won't be pulling maximum current simultaneously. Try to stay with a value approaching but not over the collective amplifiers fusing. So 250 maximum and I doubt you would blow a 200 amp from normal incident-free use. But keep a spare.
I don't see an issue with the one gauge over a length of four feet nor do I have a problem with the switch since your actual current draw will not approach the collective fusing.
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