I want to be able to test high voltage power supplies & in particular the voltage sag of fullwave rectifier valves.
I need an adjustable dummy load for the output, I would need to go from part load then to full load to test things safely with no failures.
The DC output voltages from the power supplies will range between 200v to 500v & output current can be up to 250mA. I have a Variac to control the input voltage so I can power up slowly initialy.
I have looked at several Rheostats but these are expensive & the ones I have seen are rated at around 250v & I am not sure if they will take 500v even though there total power dissapation rating is more than I require.
Will a Rheostat rated at 250v 1A--250W take 500v 250mA--125W, it seems as though it would be ok but I thought I had better ask.
I was looking at the No-Taper Rheostat that will take maximum current through the full range.
Or better still is there a less expensive way to make a variable dummy load for what I need, I thought of switching between different high Watt resistors but there may be an arcing issue that I don't want.
Is there a way to set this up using heater elements or something maybe 240v light bulbs?
Cheers.
I need an adjustable dummy load for the output, I would need to go from part load then to full load to test things safely with no failures.
The DC output voltages from the power supplies will range between 200v to 500v & output current can be up to 250mA. I have a Variac to control the input voltage so I can power up slowly initialy.
I have looked at several Rheostats but these are expensive & the ones I have seen are rated at around 250v & I am not sure if they will take 500v even though there total power dissapation rating is more than I require.
Will a Rheostat rated at 250v 1A--250W take 500v 250mA--125W, it seems as though it would be ok but I thought I had better ask.
I was looking at the No-Taper Rheostat that will take maximum current through the full range.
Or better still is there a less expensive way to make a variable dummy load for what I need, I thought of switching between different high Watt resistors but there may be an arcing issue that I don't want.
Is there a way to set this up using heater elements or something maybe 240v light bulbs?
Cheers.
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