Greetings. I have a homemade voltage divider that is working well with an old power supply (25KV monitor flyback output) but is failing with a new power supply. Can anyone help diagnose likely issues? The facts and symptoms are:
- the divider is 537:1 and is known to work with an existing 25KV DC supply operating at about 15KHz (standard flyback resonant frequency)
- the new supply claims to produce variable voltage 15KV-180KV and does throw impressive arcs (3-6" in air)
- the voltmeter across the divider's small resistor shows 1200Hz pulse rate at about 30% duty cycle from the new source
- a 200KV 10mA diode chain (10x 20KV 10mA diodes) is being used to ensure no AC voltages are coming from the new supply
- a digital meter does not lock onto the voltage across the divider's small resistor. I've tried DC and AC.
- an analog meter always shows a small negative voltage across the divider's small resistor. This happens regardless of the polarity of the connecting wires and the same needle deflection is seen regardless of the range setting on the meter.
- no sparks are thrown or ozone generated by the power supply when testing with the divider
This one's got me stumped and looking for an unusual error source. Could parasitic inductance of the divider's resistors cause this issue? Should I be checking for arcing within the power supply?
Any advice would be much appreciated.
Thank you,
-Wes