Power Mains Fuse???

Many (most?, all?) mains-powered BMD gear I have seen uses a composite IEC power mains input connector with an integral fuse holder.

However I can't find any information about the fuse.
What value (Amp current rating) is the fuse? Fast-blow or slow-blow?
Should I need a different fuse rating for 120V mains operation vs. 240V mains voltage?

I have many BMD gadgets in a portable system which I am taking half-way around the planet.
I live in 120V-land but I am traveling to 240V territories.

Should I be concerned about the power fuses?
Do I need to change the fuses to use with a different mains voltage?
If I want to take some spare fuses, what value do I need?

Amps are calculated as wattage /voltage

Basic example...
120v / 120w = 1 amp +10%
240v / 120w = 2 amp +10%

So yes the fuse ratings will change with the voltage supplied.



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120w on 240 volts is 0.5 amp

Yes we know what Ohm's Law says. I want to know what BMD says
The question is about what BMD installs in the gear. And what BMD recommends.
Does the gear come with a fuse for 120V? Does the gear come with a fuse for 240V?
What value for current (or power) does BMD use for calculating the value of the fuse?

There is no mention from the official instructions about the value of the fuse.
There is no mention at all about replacing the fuse with the value appropriate for your mains voltage.
The documentation doesn't even contain the word "fuse".
This is in distinct contrast with any other gear I have ever used in 50 years.
Other manufacturers clearly state:
"Use ___A fuse for 120V mains voltage, and use ___ A fuse for 240V."

This is an issue of safety. BMD should not be leaving this up to the end-user to guess.

120w on 240 volts is 0.5 amp

Well done Rich... Was way too early in the morning for math

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Ok, well this isn't a BMD support channel it's a user group. Questions answered by users of BM gear. If you want a definative answer from BMD grab a support ticket from their website.

Yes we know what Ohm's Law says. I want to know what BMD says
The question is about what BMD installs in the gear. And what BMD recommends.
Does the gear come with a fuse for 120V? Does the gear come with a fuse for 240V?
What value for current (or power) does BMD use for calculating the value of the fuse?

There is no mention from the official instructions about the value of the fuse.
There is no mention at all about replacing the fuse with the value appropriate for your mains voltage.
The documentation doesn't even contain the word "fuse".
This is in distinct contrast with any other gear I have ever used in 50 years.
Other manufacturers clearly state:
"Use ___A fuse for 120V mains voltage, and use ___ A fuse for 240V."

This is an issue of safety. BMD should not be leaving this up to the end-user to guess.

From my mobile using Tapatalk

Amps are calculated as wattage /voltage

Basic example...
120v / 120w = 1 amp +10%
240v / 120w = 2 amp +10%

So yes the fuse ratings will change with the voltage supplied.
From my mobile using Tapatalk

As you correctly observe, in order to calculate the current, you must know the voltage and power.
But the nameplate (and the published documentation) does not state either the voltage or the power.
The nameplate only says "100-240V 50/60V 0.5A"

Using Ohm's Law...
Does that mean 100V * 0.5A = 50W?
Or does that mean 120V * 0.5A = 60W?
Or does that mean 240V * 0.5A = 120W?

If my HyperDeck Studio Mini works OK at home (120V) with a 0.5A fuse, that means it will not be protected at 240V where I would need a 0.25A fuse.
Or does that mean that the 0.5A rating is for 240V, and I am just lucky that it works at 120V?

As far as I know it should be marked on the fuse Usually 0.25 amp or even 5 amp
It also depends on size as well
Even the voltage is marked on the fuse
It should also marked on were the fuse is located on the piece of equipment