SAE to USB adapter

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Jul 28, 2007
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3,155
Location
finger lakes ny
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1999 ST1100
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7959
Just bought one of these to get a couple USB ports on the bike. For phone.
Does this need to be fused? The ones that Amazon offers do not have inline fuses.sae usb.jpg
 
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There's never a scenario on an electrical circuit where you shouldn't have some sort of protection. You still need another lead to connect that to a battery, so you need a fuse either on the lead to the battery, or the lead that you just purchased.
 
As per the Professional Cat Confuser if you're already using an SAE connector as a charge lead to the battery then that will/should already be fused. So if plugging into there I think you'll be good but as I'm an electrical idiot don't take it as gospel.
Note to self......I am an electrical idiot.........just so I don't forget.
Upt'North.
 
And just to repeat it the 3rd time, just make sure the SAE connector from the battery is already fused and you'll be good to plug this in.
 
Hi Dean:

YES - I would certainly suggest a fuse in that circuit (likely around 2-4 amps).

EDIT: I just checked the advert for this device and it appears to have an over-current protection circuit built-in so I would guess that a fuse is NOT necessary afterall.

Pete
 
Hi Pete:

I think it is necessary - for safety reasons - to have a fuse in the circuit, even though the device might have an over-current protection feature. The over-current protection feature only addresses over-current downstream of the device, and then only if all the electronics in the device are working properly.

I think @Upt' North , @Shawn K ,and @Obo addressed the issue correctly - the power lead from the battery that the device plugs into should have a fuse on it. I can't imagine anyone installing a SAE-type lead to the battery without an inline fuse on it. That inline fuse will protect both the lead and anything connected to it (a downstream device such as the USB charger, a battery trickle charger, a set of alligator clips, whatever).

Michael
 
I bought the same one about a yer ago. It is by far a cheap chinese piece of... Anyways not trying to poo poo your new purchase but I hope its better quality. My plan was to cut off the power side of the SAE pug and use it for a compact voltmeter. Bonus that I could use it for a SAE to USB if my primary failed. It never would read correctly. Sometimes off by 5 VOLTS! I could not plug it in when new. I had to modify the plug, one of the rubber insulation bits was oversized.

I use the one linked below. Bought in April of 18 and it's working still. Seems to be well made. I fused the lead to my tank bag near the battery so this didn't need to be. Which is always a good idea.

Just to be clear. I don't think everything from China is junk. They can make some really good quality stuff.

 
Just bought one of these to get a couple USB ports on the bike. For phone.
Does this need to be fused?
No. Just like all the computers that use the same 5V USB ports this had built-in circuit protection.

You'll notice that all the USB adapter without SAE connectors have inline fuses so the presumption is you have a fused SAE pigtail.

And 99 times out of 100 the SAE pigtail attached to the battery that you'll be plugging the adapter into will have an inline fuse. If your kit had ring terminals instead of an SAE then I'd be concerned.

In the rare event you don't already have a fused pigtail such as a Battery Tender or similar SAE connection then you should get one.
 
EDIT: I just checked the advert for this device and it appears to have an over-current protection circuit built-in so I would guess that a fuse is NOT necessary afterall.
That too was my thinking so I figured I'd post the question.

I bought the same one about a yer ago. It is by far a cheap chinese piece of...

I use the one linked below. Bought in April of 18 and it's working still.
I looked at that one first !

I currently have a fused Battery Tender pigtail that is converted to coax for my heated gear.
And an unfused and unused, much heavier gauge SAE pigtail that was theoretically to be used for future jumpstarting without any plastic removal.

I guess I'll hook up another of the Battery Tender variety that I have.
 
And an unfused and unused, much heavier gauge SAE pigtail that was theoretically to be used for future jumpstarting without any plastic removal.

You should never have an unfused bolted on lead. Fuse is needed to protect the wire from becoming a giant heating/melting/fire generating device. Of course the standard disclaimer applies, each to their own... you're the one sitting on top of it.
 
You should never have an unfused bolted on lead. Fuse is needed to protect the wire from becoming a giant heating/melting/fire generating device. Of course the standard disclaimer applies, each to their own... you're the one sitting on top of it.
Was told by a few folks here that if it is to be used to jump start only, do not fuse it?
 
Just to be clear. I don't think everything from China is junk. They can make some really good quality stuff.
Really? I'm still looking for anything Chinese that lasts more than a few years...take my iPhones and iPads as examples: all made in China and none of these seem to last very long...
 
Really? I'm still looking for anything Chinese that lasts more than a few years...take my iPhones and iPads as examples: all made in China and none of these seem to last very long...
I still have an iphone 6 that is nearly 6 years old and still works fine. I also have the sae to usb pigtail that works just as designed.
 
DeanR said:
Was told by a few folks here that if it is to be used to jump start only, do not fuse it?
Fused or unfused you shouldn't actually jump start it with any SAE connector or typical pigtail. By that I mean cranking the engine while connected. Letting the donor bike charge your battery for a few minutes then disconnect and try starting the bike. You could probably leave the bikes connected while trying to start. If your bike starts up after a few rotations or two the cables might be fine.
 
You should never have an unfused bolted on lead. Fuse is needed to protect the wire from becoming a giant heating/melting/fire generating device. Of course the standard disclaimer applies, each to their own... you're the one sitting on top of it.

1575994258420.png
His un-fused lead shorted....
 
Fuses are chosen to protect the WIRE, not the equipment at the end of the wire. One of the exceptions to that rule would be inline fuses protecting motor windings, though you could say those are wire, too. If your SAE connector is used for a battery charger, or other high current item, and it has a 15 amp fuse, the wire in that adapter might not be large enough to carry a large enough current to blow the fuse before heating up. Why? If the wire chafes at a point downstream from the fuse, you want it to be able to carry sufficient current to blow the fuse (open the overcurrent device in electrician's lingo) without overheating and melting the insulation and causing damage to other wires bundled nearby. A two amp fuse suggests that the device maker is protecting very light wire when the USB port is rated for 1 amp.

There are a lot of videos on youtube of guys welding with the same eye protection.
 
I currently have a fused Battery Tender pigtail that is converted to coax for my heated gear.
And an unfused and unused, much heavier gauge SAE pigtail that was theoretically to be used for future jumpstarting without any plastic removal.

I guess I'll hook up another of the Battery Tender variety that I have.


I'd like to see your "jumpstating" harness before saying this officially but...I wouldn't use it for that. Don't think a SAE type would be up to the task. How much time are you saving by not removing the seat, saddlebag and sidecover? Two minutes tops? I'm a lazy procrastinating work avoiding wrencher but never in that much of a hurry. Heck two of those are removed with just a key.

Really? I'm still looking for anything Chinese that lasts more than a few years...take my iPhones and iPads as examples: all made in China and none of these seem to last very long...

Most of the best high end flashlights are MIC. I have a few that are several years old. One in particular has had a hard life and still works as new. Grated the batteries are Japanese. Never will I buy a MIC cell. I don't like random surprise fires!

I use the Motopower USB outlets. High output, though not QC outlets, and very well built. Never had a failure.

Here’s the link...

I prefer non quick charge. Much better for battery life. I found the one you linked on amazon US. If mine dies I'll try it.

 
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