One trick we have used many times is to replace the fuse with a light bulb for testing the trigger point of the over-voltage crowbar. Or put the light bulb in series with the SCR's anode. Cheaper than a bunch of fuses and easier on the power supply. Automotive bulbs or even headlamps can be used in supplies hefty enough.
Al, K9SI >In [email protected], "Bob M." <msf5kg...@...> wrote: Whether it's the SCR itself, or the sense circuit driving it, something is causing it to fire and blow the fuse. You'd need to measure the actual output voltage of the supply to see if it's going that high or if the SCR is being falsely triggered. Of course, you only get one shot at trying it before the fuse blows.
