My current project has a Schurter IEC power entry module that fuses both the line and the neutral. For the sake of safety I need to bypass the fuse on the neutral leg (USA 117 volt service). That means I want to put a shorting slug inside instead of the fuse. The module expects a 5 X 20 mm fuse which equates to about 0.20 inches diameter which isn't any tube stock size that I find at the hardware store.
Has anybody done this already?
Has anybody done this already?
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They are both fused in case your power socket in the wall is mis-wired - your neutral might actually be live in such a case.
If you are using the device on a known good wall socket, just install a higher current rating fuse in the neutral as compared with the live so that the live will blow first.
If you are using the device on a known good wall socket, just install a higher current rating fuse in the neutral as compared with the live so that the live will blow first.
> For the sake of safety I need to bypass the fuse on the neutral leg
No you do not.
In Wall wiring restricts breaking the White. In-Appliance wiring is not restricted.
Inside appliances, the assumption is that you will UN-PLUG before opening the case. If you choose to stick your fingers in there live, that is your responsibility. And you would be wise to do visual and beeper-checks if you suspect power-entrance problems, before you do live probing.
Note that there is no assurance which wire is "white". Maybe all your outlets are wired correctly, but what if you go to a friend's house? White/black swap is very common.
If you really do not want the fuse to blow, get a 16A 5x20 fuse. With a 1A-2A in the assumed hot leg, the 16A is unlikely to blow first.
No you do not.
In Wall wiring restricts breaking the White. In-Appliance wiring is not restricted.
Inside appliances, the assumption is that you will UN-PLUG before opening the case. If you choose to stick your fingers in there live, that is your responsibility. And you would be wise to do visual and beeper-checks if you suspect power-entrance problems, before you do live probing.
Note that there is no assurance which wire is "white". Maybe all your outlets are wired correctly, but what if you go to a friend's house? White/black swap is very common.
If you really do not want the fuse to blow, get a 16A 5x20 fuse. With a 1A-2A in the assumed hot leg, the 16A is unlikely to blow first.
I think about it like this: If both the line and neutral are fused then both of the fuses are in series with the load and it will be a contest as to which fuse blows first during a fault. If the neutral's fuse blows first and the ground wire really isn't grounded then you are stuck with a faulted piece of gear with no ground that is connected to 120 volts. At least the neutral is ultimately grounded at the circuit breaker box. So there should only be one weak link: the 120 volt line's fuse.
I like korpberget's suggestion for the bolt. Now I have to find a brass M5 bolt to cut.
I like korpberget's suggestion for the bolt. Now I have to find a brass M5 bolt to cut.
I suggest you fuse the Neutral side at about 3times that fitted to the Live side. Then you have a chance that only the close rated Live fuse will rupture when a prolonged overload occurs.
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