Bridge Diode Rating

[luvdunhill]

so, I've been playing around with some diodes on a power supply and found some I like, but I think I'm cutting it too close with the current rating. The transformer is 82VCT 50VA R-core and I have a 300mA fuse on each rail after the main supply capacitance, which is around 3000uF per rail. I wouldn't expect any more than 300mA per rail, hence the fuse choice. That being said, there is in-rush and the like to consider, and blowing a bridge isn't too exciting in my book. So, without admitting how stupid I was, and how low I went... in your opinion, what's a good rule of thumb?

[cetoole]

so, I've been playing around with some diodes on a power supply and found some I like, but I think I'm cutting it too close with the current rating. The transformer is 82VCT 50VA R-core and I have a 300mA fuse on each rail after the main supply capacitance, which is around 3000uF per rail. I wouldn't expect any more than 300mA per rail, hence the fuse choice. That being said, there is in-rush and the like to consider, and blowing a bridge isn't too exciting in my book. So, without admitting how stupid I was, and how low I went... in your opinion, what's a good rule of thumb?

Well, you dont provide all the needed information, so some assumptions must be made. I assume your rectifier is a FWB, though you did specify that you are using a 82VCT transformer. Also important, and my assumption is yes, but are you using a pure cap input filter? Finally, what is the DCR of your transformer? I would tend to guess maybe 10ohm or so, but it makes a pretty big difference. You can use PSUDII to get a pretty good picture of what is going on with your power supply. Rule of thumb though, I would stick with 2A rated diodes or higher, though I have used 1A rated diodes for extended periods of time with no ill consequences. That said, I can be a glutton for punishment.