10 Amp switch 15 Amp fuse

[Eniaro]

So, my VEVOR ultrasonic cleaner switch melted.
I contacted VEVOR, they sent me a new one after almost a month of back-and-forth messages.

Over the past few months, I've also replaced switches on heat presses (from various brands) with similar failures. What caught my attention is that the switches are always rated for 10 amps, but the fuses are always for 15 amps. this mismatch?

I've started to second-guess my knowledge. Everything I've researched says exactly what's happening to these switches.
This issue hits far too close to home. I'm concerned that so many devices out there might share this same potential fire hazard. Vevor seems well aware of the problem, judging by their quick association of a "burning smell" with the switch failure.

Is there a reason for the rating mismatch?

[sam_sam_sam]

I would agree with you that there is a mismatch between the switch rating and the fuse that is used in this device
If I were doing this repair I would not use this type of cord connector I would just hard wire it to inline fuse holder that is rated for 30 amp and use a power cable that is rated for 30 amps ( make sure that you use a 15 amp fuse that it calls for) and be done with it so you do not need to replace these parts again

Now that just me and I really have issues with manufacturers that cut corners with inferior parts and do not use the correct type components that correctly rated for the device REALLY

I personally do not like this particular model of this product because this one is not ones that I have seen before where there is a power rail that can be seen and if cut could be done with what I have bellow

The other option if has a control relay then you could just use the power supply connector and use the fuse for the control circuit if can be separated and put in a in line fuse for the heater element

[stj]

well i dont like any of that.
is the switch seperable from the moulding?
you can get 16-20A switches that may fit.
a bigger issue is that 20mm fuses arent really intended for more than 10A because of the size - and you should be using ceramic for mains anyway.
your half-ass mains voltage dousnt help - it means everything needs double the current compared to the rest of the world.
i'm off now to make a coffee with my 3KW kettle that boils almost 2L of water in about a minute

[stj]

oh - just looked at the picture.
so it's not the switch burning - it's the fuse holder clips.
well - like i said, 20mm is only rated for 10A - infact most are only rated upto 6.3A

[redwire]

The entry module has no North American safety approvals, like UL/CSA. Better ones use copper, not aluminium. So it's junky part in the first place. The fuseholder jaws need to be thicker for high current. Same for the IEC power cord.

Second, I would say the failure could be due to the unit having a terrible (capacitive) power factor or ultrasonic ripple currents if the primary cap is fading away.
Nobody needs 15A (fuse) worth of ultrasonic that I know of. It might be missing an inrush NTC or just has very high mains current peaks that will overstress components.

Post more pictures, most important is that a shorted power mosfet does clear the fuse and not burn up something else.

[Eniaro]

The switch assembly taken apart...

[Eniaro]

Here's another switch that I replaced recently.

[stj]

so the bus bar linking the fuse holder to the switch failed,, maybe soldering those bars will help.

still, your overloading the unit and the design is fine.
IEC cables are mostly rated to 10A, 20mm fuses officially only go to 10A because they arent long enough to break a high current arc
dont blame the chinese if you melt it by going 50% above the rating.
blame them for fitting it maybe, but i'm not sure there is another way unless they use a seperate 32mm fuse holder

[stj]

The entry module has no North American safety approvals, like UL

you can just buy those now - i found that out when i was trying to cross-reference a UL number.

[Eniaro]

so the bus bar linking the fuse holder to the switch failed,, maybe soldering those bars will help.

still, your overloading the unit and the design is fine.
IEC cables are mostly rated to 10A, 20mm fuses officially only go to 10A because they arent long enough to break a high current arc
dont blame the chinese if you melt it by going 50% above the rating.
blame them for fitting it maybe, but i'm not sure there is another way unless they use a seperate 32mm fuse holder

I'm not sure if you're trolling.

1. First of I'm not blaming any nationality. This is about the poor design
2. I did not build these devices, they're manufactured like this.
3. If something is designed to use 10A and uses 10A rated components you're at 100% at normal use with 0% tolerance.
4. The entire concept of a fuse is to cut power should it exceed what is rated.
   • Therefore if the device's components are rated at x then the fuse should cut at x and for safety there should also be tolerance.
   • In the US the maximum is 80% of what the outlet is rated eg max load on a 15A outlet is 12A

The reason for my post is to point out the fire hazard in design. I specifically called out Vevor because I for one did not expect this from them since I've bought other tools from them which all worked as they should.



My last post was a switch from a heat press rated at 16A with a 15A fuse. While the configuration was built with tolerance in mind the switch assembly failed which is what I'm seeing quite frequently.

[stj]

i wasnt aiming any of that at you, it was intended for Redwire

the problem is that most of the world is 230v,
so half the current.

when china or wherever else adapts a design for the north american region they have limits on how much current the parts can handle without things like redisgning entire casings to use totally different inlets and larger fuse holders.

this is not normally an issue, but once your talking 2figure numbers for current the parts that are standard for the rest of the world become a problem and the bigger stuff needs different holes in panels etc.
that IEC connector is a "C14", for the current you need it should be a "C20"

[redwire]

Eniaro, spade connector's limit is 16A and even then they must fit perfect. They look a bit off size.
Pic related- the switch, common from china is to have very large holes and notches on the tabs which lowers contact area.

What happens is the spade connector and the crimp has resistance and generates heat. The switch also makes heat due to contact resistance. It can be too much and once things melt a bit, it gets worse. The two have be right.

Also in OP the fuse holders going to the busbar are super thin, I have bought 10A or 20A fuse clips like Littelfuse 100 Series and they are much thicker than pictured.

Still curious about OP's ultrasonic cleaner. I'll bet it has no PFC and huge mains caps to give high peak input currents.
The average current can be low but high peaks can make an appliance strangely eat connectors, switches. Or the original part is just junk.

[petehall347]

i see a fair bit of poorly manufactured parts that melt because of poor connections etc . even the fuses themselves . here is a good example of dangerous crap shit i get to look at . note the ac mains switch that they call the Leakage Protection Switch.. https://www.amazon.co.uk/Windshield-.../dp/B07Z9B8GNS

[stj]

my advice - for now.
remove the interconnector strips and fit a seperate 32mm fuseholder with a 15A CERAMIC fuse.
the switch is o.k.
and the C14 is working to it's limits but we will overlook that unless/until it cooks - then you can use a C20 style inlet & cable.

it's got nothing to do with quality, i keep trying to point out that 2 out of 3 of the parts on the panel are NOT rated for 15A and never will be regardless of what brand you buy.
Amazon sell junk btw,
https://www.youtube.com/watch?v=B90_SNNbcoU
but thats hardly news - they just sell the worst stuff they can find on TaoBao with a big markup for Bezo's

[redwire]

Product Safety Report: Vevor Ultrasonic Cleaners (2205-0322) (2205-0324) (16 August 2022)

Hazard: The products present a high risk of electric shock as the products are inadequately earthed and of inadequate size which caused the earthing wire to overheat and melt the insulation. The plug also failed to comply with BS1363-1 as the earthing pins had less than 3.9 mm thickness, which is below the minimum required.

Corrective action: Destruction of the product at the border.



They might have skimped on the connections, the amount of metal used.
Wonder what model OP has. The 30L is 600W Ultrasonic plus 500W heater.

[stj]

typical u.k. section18 bullshit,
an IEC connector never has 3.9mm of thickness.
are they going to destroy *everything* at the border?

[Eniaro]

Product Safety Report: Vevor Ultrasonic Cleaners (2205-0322) (2205-0324) (16 August 2022)

Hazard: The products present a high risk of electric shock as the products are inadequately earthed and of inadequate size which caused the earthing wire to overheat and melt the insulation. The plug also failed to comply with BS1363-1 as the earthing pins had less than 3.9 mm thickness, which is below the minimum required.

Corrective action: Destruction of the product at the border.



They might have skimped on the connections, the amount of metal used.
Wonder what model OP has. The 30L is 600W Ultrasonic plus 500W heater.

I have the TH-100A (30.L) "800W Heater 600W Ultrasonic" says the label

[redwire]

I'd get a new IEC entry module - the old one the compression rivets on the busbar likely junk too, that might have been the poor connection that started it all.
Check the power cord IEC end did not melt too and it is as stj says it all should be rated for higher current. 1,400W 120VAC is almost 12A.

That UK section 18 baloney I thought is funny - if I could I would be raiding the garbage bins over there. Somebody should let Vevor know.
The ground wire "overheating" it only has to take current long enough for the breaker to trip, if there is a ground fault.
One product I designed and submitted for approvals, the certifier put 15A through the ground for an hour and checked temps... their assumption is at 15.0A the mains breaker trips but at 14.99A it doesn't.

[stj]

u.k. customs are a joke,
they mostly steal stuff like alcahol, automatic knives and *anything* shaped like a gun - even a bottle of taquila shaped like a gun.
in the past they used to take porn video's and magazines and weed/tobacco
obviously they are just robbing people so they can party after work!

[petehall347]

u.k. customs are a joke,
they mostly steal stuff like alcahol, automatic knives and *anything* shaped like a gun - even a bottle of taquila shaped like a gun.
in the past they used to take porn video's and magazines and weed/tobacco
obviously they are just robbing people so they can party after work!

only problem i had is when on the way to a family wedding . didn't have anything to declare .they saw me on camera finishing my smoke before boarding . had to beg them to not strip the hire car after they led the dog directly to my seat . still not sure if they were taking the piss or not . i have been told many times i look like one of the furry freak brothers but that's not usually a problem