Topic: Idea for VMS (& other 12v m-tip reverse polarity gear)

[todd e]

It ain't pretty, but tests correct and sends the power properly.
Unfortunately the 1a, slow acting fuse appears to have been blown and needs replacing (within the VMS02ib).  One step fwd, two steps back.

[fanofjam]

Good work Todd!  Looks don't matter if she functions properly!

[fanofjam]

Todd...I forgot that the VMS has a fuse.  Is it a silver component that looks a little bit like a top hat on the front board? 

FWIW, whenever I've had a power short that kills my VMS (I think it's happened twice), it also burns out either one or both of the diodes on the front board that is located immediately downstream from where power connects to the board.  In my case, both times the diode was fried, so there was no mistaking the failed component(s), but that fuse may be something I need to replace and one of the reasons I haven't been able to get my units working.

If that silver cylindrical thing is a fuse, can you please let me know what the model/part number is because I've got a couple of VMS's that I'm going to work on to see if I can get operable.  They're waiting for me at home for when my California work assignment ends in November.  Obviously, I'll want to locate and replace that fuse as one of the first things I do.

TIA

[todd e]

Todd...I forgot that the VMS has a fuse.  Is it a silver component that looks a little bit like a top hat on the front board? 

yep, i sourced a similar rated 1a slow acting fuse for that, it should arrive shortly and i'll swap it out. 
i found the exact lookng fuse, but couldnt figure out how to order properly.  littelfuse 0278-000  (i would obviously prefer the exact fuse)

FWIW, whenever I've had a power short that kills my VMS (I think it's happened twice), it also burns out either one or both of the diodes on the front board that is located immediately downstream from where power connects to the board.  In my case, both times the diode was fried, so there was no mistaking the failed component(s), but that fuse may be something I need to replace and one of the reasons I haven't been able to get my units working.

IF mine were shorted from the external power supply i would have expected a diode to blow, since there is no fuse on that power pathway.  the fuse appears to be only in effect, for the internal battery portion of the power supply.

If that silver cylindrical thing is a fuse, can you please let me know what the model/part number is because I've got a couple of VMS's that I'm going to work on to see if I can get operable.  They're waiting for me at home for when my California work assignment ends in November.  Obviously, I'll want to locate and replace that fuse as one of the first things I do.

TIA

this is the fuse, i'll send ya some since you've helped so much.  the 411 for the fuse is thanks to nick and someone on the inside at schoeps factory.
https://a.co/d/iGKGwwi