Is it possible to make a transformer safe without a primary fuse?
Is this Weller safe?
It gave some smoke out, but was there a real possibility of a fire or an electrical hazard?
You consider using the mains breaker as a primary safety feature of your product???
I have a WES81 230V version and it has a IEC power connector with integrated fuse. So do they only use a primary fuse on the 80 watt model and not on the 50W? Or do they only use a fuse on the 230V model and not on the 110V? Is it only fused for the EU market?
Someone on Youtube said their EU unit does not have a fuse, but I have yet to see actual visual evidence of this.
I'm new here but I am trying to upload a picture of the inside of my WE1010 bought here in Sweden in October.
Thanks. Any fuse further in the primary wiring?
yea and whats gonna break the circuit? A circuit breaker. Or a mains fuse. How is that acceptable?
How do you ensure the transformer will not go full short circuit? The EEVBLOG circuit breaker went off, that means the transformer failed or its a shit spec.
An inherently protected transformer meets isolation requirements also under any overload conditions so it will not be short-circuited.
Someone questioned Weller and got a more detailed reply from a product engineer (specific to Australian supplied units).
Guess he didn't get the "don't say anything" memo:QuoteThank you for contacting Apex Tool Group.
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None of the hand held line voltage soldering tools have fuses
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A fuse is not required on small transformers like this. The primary winding wire is small enough that it is allowed to be the "fuse" in a severe malfunction fault condition. Standard (non-switching) wall warts are like this as well. They tend to be designed to be short circuit proof simply by being impedance limited, they simply can't draw enough power to burn up in normal operation but a fault like shorted turns, connection to completely the wrong voltage or even the nasty square wave that comes out of cheap inverters will blow the winding open. They are contained within housings that are either metal or plastic that is (supposed to be) flame retardant enough to not burst into flames and burn down completely before the winding blows up and opens the circuit. Of course, I'm not sure that today's typical chinesium-grade plastic is as flame retardant as it should be but Weller doesn't need to put a fuse in there (though it is obviously a good practice) and I doubt it would actually burst into flames with any input voltage. It might fill your lab with smoke to remind you of your blunder if you leave it plugged in, of course, though!
A fuse won't always prevent smoke from a device anyway. For example, a typical computer power supply will happily pump out 500 watts of 12 volts without going into overload protection. You can get a whole lot of smoke out of something connected to one of those babies while it is still perfectly within it's input fuse range and output protection. Should every device, perhaps every chip even, connected to it be required to have a fuse just in case there is a malfunction that might produce smoke?
If I connect something that is rated for 120 volts to 1000 volts, it is going to fry. Probably more quickly than on 240 volts. Maybe with more smoke, maybe a quick death and less. There will be some sweet spot on most devices (often even with a fuse) where it is likely to go into thermal runaway meltdown at some particular input voltage or fault condition. That's what enclosures are for. A fuse does not 100% stop components from emitting smoke.
If they were regularly actually bursting into flames, I would be concerned, but a PEBKAC on Dave's part doesn't instantly make the device itself inherently dangerous. This is why things like actual UL listing (unlike Batterizer's UL tests) do things like take a blowtorch to your product, to see what would happen when someone puts a 15A fuse in your 1A fuse holder. Does the enclosure actually stop the flames? What happens when we put 5000 volts on it? Does it remain "safe" per the standards, even though the device doesn't survive, etc., etc.
A fuse is not required on small transformers like this. The primary winding wire is small enough that it is allowed to be the "fuse" in a severe malfunction fault condition.
your not supposed to blow breakers. your not supposed to shut down an entire work bench and possibly room lights and smoke the joint up because of a 50 cent part. whoever designed this standard is a fucking moron
your not supposed to blow breakers. your not supposed to shut down an entire work bench and possibly room lights and smoke the joint up because of a 50 cent part. whoever designed this standard is a fucking moron
They were drafting an electrical safety standard. Not a convenience standard.
yea i wanna see this tested with and without a fuse on a proper 240v line thats low impedance with a bypassed breaker, feeder breaker only at 50 or 100A
Anyone able to find the manufacturer of this transformer? Someone should buy a pair, plug it into 230/240V outside with and without a fuse just to demonstrate the difference $0.2 makes. Photonicinduction style?
They were drafting an electrical safety standard. Not a convenience standard.
whats going to short out at 450W and current limit itself? :wtf
parts are just gonna fail to a happy impedance like that? its probably gonna trip. What part is going to make plenty of smoke like a giant transformer winding dissipating 500W @ 0.3 ohms on a 12V rail?
why did it blow the breaker if its supposed to fuse??
Anyone able to find the manufacturer of this transformer? Someone should buy a pair, plug it into 230/240V outside with and without a fuse just to demonstrate the difference $0.2 makes. Photonicinduction style?