Discharging capacitors, PSU-testing with dummy loads
Posted: Tue Aug 29, 2017 12:05 pm
I have two questions concerning before and after recapping an Atari PSU:
1) what is the safe and proper way to discharge a (high voltage) capacitor in the PSU?
I prefer not being electrocuted while attempting to desolder it
2) Regarding the use of PSU dummy load resistors (so I can test the PSU alone without any risk to the computer) you explain to connect the 10 Ohm resistor between blue and black (if the colours are standardized between the various Atari PSUs this should mean to put it between the -12V and GND outputs, right?).
Likewise, the 2.2 Ohm resistor between red and black (+5V and GND?).
Does this only allow for testing the +5V and -12V outputs?
For testing the +12V and -5V outputs, do I need to move the resistors to those pins and GND, or will the above allow the entire PSU to be tested?
I suppose 30 seconds should be enough to test if the voltages are right. Is there a 10% tolerance?
1) what is the safe and proper way to discharge a (high voltage) capacitor in the PSU?
I prefer not being electrocuted while attempting to desolder it
2) Regarding the use of PSU dummy load resistors (so I can test the PSU alone without any risk to the computer) you explain to connect the 10 Ohm resistor between blue and black (if the colours are standardized between the various Atari PSUs this should mean to put it between the -12V and GND outputs, right?).
Likewise, the 2.2 Ohm resistor between red and black (+5V and GND?).
Does this only allow for testing the +5V and -12V outputs?
For testing the +12V and -5V outputs, do I need to move the resistors to those pins and GND, or will the above allow the entire PSU to be tested?
I suppose 30 seconds should be enough to test if the voltages are right. Is there a 10% tolerance?