Old Toy Robot (Omnibot 5402) - Fuse Question

Looking to get a replacement fuse for an old Tomy Omnibot (5402) - manual says it needs a 6V 5A fuse (the one in the robot is blown). Can I use a higher rated fuse (120V 5A?) can’t seem to find 6V fuses anywhere. Thanks in advance!


Could you post a picture of this fuse and the measurements?

Measures 1.18 inches/30mm

Yes, you can use a higher voltage but not a lower one. I usually get these common glass fuses at a local auto parts or, hardware/home improvement store.

Thanks very much @PaulHutch! Ordered some :slight_smile:

Paul is correct in the statement that fuses of higher voltage rating can generally be substituted for those of lower voltage rating.

It’s possible that the 5A/6V specification is not referring to the spec for the fuse itself, but to the expected maximum values of the power that it needs to carry–this would be an atypical and ill-advised way to specify a fuse, but seems likely to be the case here. The other plausible explanation is that it’s a misprint meant to refer to a 5A/600V fuse, but such a spec would be more suited to industrial robots, not toy robots.

More to the point, it would appear that the fuse pictured may actually be rated for 7.5A, based on the markings. This would be consistent with the first theory above, in which case the 031107.5M or something similar might be a suitable option. A 5A fuse carrying 5A will nuisance-blow in relatively short order, so a 7.5A fuse in a circuit expected to carry 5A under normal conditions would be a better choice. And 6V corresponds to 4x alkaline cells or one 6v lead-acid battery, which seems a lot more likely for the application in question.

See this resources if you’re interested in further info on what the various selection parameters for fuse products mean.

Well spotted I only noticed the 5.

Hmm, this is 20 to 40 year old toy. It may be that at some point as the mechanics got old and had increased friction somebody replaced a 5A fuse with a 7.5 A fuses to keep the toy running with increased starting current demands on the motors. If that’s what happened and it now has tripped a 7.5A fuse, I’d bet there will be more dead parts than just the fuse.

Thanks all - can confirm it was a 5A fuse in the Omnibot that I shared in the picture above (not 7.5A, sorry for the bad angle!).

The manual says 6V 5A fuse - so I got some 120V 5A fuses. Should do the trick! Will let you know if it all goes horribly wrong :wink:

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