looking for a radial fuse for a Cosel ACE450F

Thread Starter


Joined Jul 5, 2021
Hi, I'm sorry if this is the wrong place to ask this question but...
I have recently diagnosed and repaired a fault on a Cosel ACE450F modular power supply. The fault was essentially caused by liquid ingress which had shorted a few resistors to some pins on a nearby connector block. I replaced all resistors which looked like they'd been BBQ'd and then had a probe about using my IV (octopus curve tracer) only to find that some resistors next a VDR (reset IC) also looked a little dodgy. Ultimately I decided to replace the VDR itself (which was an R957B) and the surrounded resistors as well. Finally I replaced a radial fuse which had been also taken out. The power supply now works like a dream. I've tested all outputs at nominal loads using my programmable DC load and let each output run for a good half hour. SO I'm happy the repair is complete.... well almost...

The original radial fuse which I removed form the device was rated at 4A - 400VDC. However, I only had 4A - 300VAC fuses available in my workshop. So not only is the opening voltage underatted but it is also rated in AC as opposed to DC. As you can imagine I don't really fancy sending this back to the customer until it has the right fuse inside. The problem is however that I cannot find one anywhere. I believe the MFR is littlefuse but I can't find anything similar on their website and I've tired looking through all the usual retailers (farnell, mouser, digikey etc) but I'm finding that most of the fuses display VAC ratings but not VDC.

I'm a little lost right now because even though the repair is basically done I'm just going round in circles at the last hurdle :(

If anybody on here has any suggestions for how I can resolve this it would be very very much appreciated.