Question about piggyback fuse holders

[Geo Jeep]

I'm looking to install a 12v power port in my bed to run some small wattage items but definitely my inflatable SUP air pump. That requires 110 watts. By my calculation I need 10 guage wires and a 15 amp fuse. In looking at the piggyback fuses on line, it doesn't specify the guage of the wire for the holder but they often provide 5, 10, and 15 amp fuses all with the same fuse holder. Do I need to worry about the wire size there? Or do I not need to worry since it's so close to the power source. Seems odd I would need 10 guage from the back and then wire into a piggyback that only has 14 guage (or whatever it is). Thanks in advance!

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[Mr._Bill]

For something like that, it's probably better to come off the battery post with appropriate sized wire and use a inline fuse.

 

[Geo Jeep]

For something like that, it's probably better to come off the battery post with appropriate sized wire and use a inline fuse.

That's my other option. I wanted it to be fused so it only works when the Jeep is on, but for as infrequently as I'll use it, it's probably not a big deal. Thanks for the reply.

 

[Mr._Bill]

That's my other option. I wanted it to be fused so it only works when the Jeep is on, but for as infrequently as I'll use it, it's probably not a big deal. Thanks for the reply.

You could feed it off one of the AUX Switches. I think 1 and 2 are rated for 40 amps. Use an inline fuse rated for the capacity of the plug at the end of the wire. Then you can control when it is live.

 

[Kevin_D]

At 110W, you'll be drawing less than 10A.
Most of the piggyback fuse holders that I saw had 16ga. wire. I found one that had 14ga wire, though. 14ga. wire is conservatively rated at 15A. Especially for as short a run as the adapter, you'll probably be OK, unless you're constantly overloading it, in which case the wire on the piggyback adapter will act as the fuse...
10ga. wire will easily handle 30A.

Don't forget to figure in voltage drop, as it can be quite significant on longer (>20ft.) runs.
Even at 20ft., a 10ga. wire carrying 20 amps will drop ~1V.

Kevin

 

[Geo Jeep]

At 110W, you'll be drawing less than 10A.
Most of the piggyback fuse holders that I saw had 16ga. wire. I found one that had 14ga wire, though. 14ga. wire is conservatively rated at 15A. Especially for as short a run as the adapter, you'll probably be OK, unless you're constantly overloading it, in which case the wire on the piggyback adapter will act as the fuse...
10ga. wire will easily handle 30A.

Don't forget to figure in voltage drop, as it can be quite significant on longer (>20ft.) runs.
Even at 20ft., a 10ga. wire carrying 20 amps will drop ~1V.

Kevin

Thanks. I looked at a couple of online resources to come up with the 10 ga hopefully that's good.

 

[Geo Jeep]

You could feed it off one of the AUX Switches. I think 1 and 2 are rated for 40 amps. Use an inline fuse rated for the capacity of the plug at the end of the wire. Then you can control when it is live.

I thought about that too. I don't have aux switches at the moment but plan on adding maybe the Voswitch version when I find the need. So more than likely an inline fuse right to the battery should do for now until I get some switches.

 

[Kevin_D]

One other thing…
Don’t try running a 30A piggyback adapter on a circuit with an existing 5A fuse! Pick one with a larger fuse (20-25A) already there.

Kevin

 

[Blade1668]

I'm in agreement with Kevin_D and then some on use of large enough wiring plus second on fuse close to batteries as possible. I wired power port and SAE plug to location that the 110 power port is located. I could run 40 amp from it with the wire I used easy.

 

[Geo Jeep]

One other thing…
Don’t try running a 30A piggyback adapter on a circuit with an existing 5A fuse! Pick one with a larger fuse (20-25A) already there.

Kevin

For sure. My plan was to use a 15 amp on a 15 or 20 amp, or I may just end up running an inline fuse and go direct to the battery for now until I get switches. With the inline fuse close to the battery.

 

[Geo Jeep]

I'm in agreement with Kevin_D and then some on use of large enough wiring plus second on fuse close to batteries as possible. I wired power port and SAE plug to location that the 110 power port is located. I could run 40 amp from it with the wire I used easy.

what wire size did you use and did you find an inline fuse with wire that matched up what you ran from the bed?

 

[Blade1668]

10 GA wire at least and have found fuse holders with that gauge of wire. I'm going down road with friends, not near my JT or I'd send a photo. I'll try to see if I've got a few photos on my phone.

not what I used on it but wire from the stock I used. I use "marine" grade wiring stuff as much as possible.

 

[Lost1wing]

Don't mean to butt in, I installed 12v power in the bed just like the way you are looking at. The exception is that I have it connected to the aftermarket aux switches. So even with the truck on, I have control of the 12v power in the bed. The in-line fuse holder I chose was 30amp. I just put a 20amp fuse in it. The wire is not marked on the fuse holder. The kit that I ran to the bed came with an 8ga wire.

 

[Lost1wing]

Advanced auto sells the 30a in-line fuse holder that I used. It shows it to be 12g. I found an in-line fuse holder on Amazon with a 10g wire.

 

[Panthers65]

For something like that, it's probably better to come off the battery post with appropriate sized wire and use a inline fuse.

Agree, Find a 30a relay kit, run the power wires through the relay directly from the battery, then you can use a small 5a piggyback just to switch the relay on and off via a 12v switched fuse source.

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