How do I spec out a damaged thermal fuse?

[Vespa Vic]

I have a DeWalt DXAEJ14 (portable jump starter, air compressor, USB...) I was inflating a large equipment tire that exceded the 10-minute max duration I should have run the compressor (followed by a 30-minute cool-down break). I read that in the manual after I damaged the fuse...
When I returned to the unit (more than 20 minutes), the compressor was off and nothing would operate on the power station. I determined the thermal fuse blew. How do I spec out a replacement fuse? I don't have, nor can I find any details to tell me the temp of this fuse. The fuse has the following information printed on it: A-YX01, E478338, 94V-0 and finally HRS2057-C. I wasn't able to generate any results with my Google search with those numbers.

Does anyone have any help for me? Thank you in advance.

 

[unclejed613]

right off the top "94V-0" is a flame retardance spec. "E478338" is a UL document number, so we're left with the other two numbers. a picture might also help narrow down the guesswork.

 

[The March Muppet]

Where is the device located? Rather what specifically is it protecting? it would not be difficult to make an educated guess at to the maximum temperature any specific discrete - or a stator winding - should be protected from reaching. Presuming of course the thermal fuse is in fact installed to protect the actual equipment and not the environment.

With a bit of margin for thermal coupling delay, I'd take a wild shot at 100-105 C being somewhere roughly in (or in the parking lot) of the ball park.

If all else fails and the unit is bin fodder anyway, bypass it and be mindful of the duty cycle,

 

[Vespa Vic]

Yes, bypassing and watching run times and temp makes for a cheap practical resolution.

 

[rjenkinsgb]

Unless the "copper" track on that PCB is actually a plated low-melting-point alloy, that is not a thermal fuse but a crude overcurrent protection fuse, to prevent the supply cable catching fire in case of a catastrophic fault...

You may find the motor is burned out.

Try just a 10A slow blow / automotive fuse and see what happens?

 

[unclejed613]

the copper near the solder on the right is open circuit.

 

[rjenkinsgb]

the copper near the solder on the right is open circuit.

Exactly - and if it is just copper, it's not a temperature sensing fuse.

 

[shortbus=]

Exactly - and if it is just copper, it's not a temperature sensing fuse.

But it could be a "fusible link" like they use in cars. A smaller guage wire or in this case a smaller ounce of copper board, that melts when over loaded. https://en.wikipedia.org/wiki/Fusible_link

 

[rjenkinsgb]

But it could be a "fusible link" like they use in cars. A smaller guage wire or in this case a smaller ounce of copper board, that melts when over loaded.

Yes again, as I said in post #5.
A simple over-current protection device for if there is a catastrophic failure of the compressor motor, to prevent the motor supply wires catching fire.

 

[The March Muppet]

could be a "fusible link" like they use in cars.

Could be. Which In automotive use is really nothing more than a length of wire of a smaller gauge - the distinctive spacial sauce only that the insulation doesn't melt through or burn. Can't recall how many AWG "up" (from the actual circuit) a link was supposed to be - but yeah .. I like where you're going. Determine the rating for the pigtails based on gauge, derate with the next size down automotive fuse and give 'er.

 

[shortbus=]

Can't recall how many AWG "up" (from the actual circuit) a link was supposed to be

quote, "An electrical fusible link is a type of electrical fuse that is constructed simply with a short piece of wire typically four American wire gauge sizes smaller than the wire that is being protected. For example, an AWG 16 fusible link might be used to protect AWG 12 wiring. Electrical fusible links are common in high-current automotive applications. The wire in an electrical fusible link is encased in high-temperature fire-resistant insulation to reduce hazards when the wire melts.[1] [2] " From - https://en.wikipedia.org/wiki/Fusible_link

We made the wire for them where I worked, they had Teflon insulation on them. It was the same wire inside as standard car wire, just the different insulation. This was at Delphi Packard Electric in Warren, Oh.

 

[unclejed613]

you can fix the original with a solder blob over the part that's burned open, as you still have a similar fusible section on the other end that looks intact.