Question: I am wondering if Keithley's current compliance limit set to a low value (let's say 500uA) during tests using 1000V of voltage can help protecting operators from accidentally zapping themselves.
I would assume it is not enough for any safety certification (it's a bonus if it can be counted towards that) but even practically, is there a point in setting this low current limit from a safety perspective?
Answer: The current compliance limit should not be used as a safety feature for operators and is intended as a power limiter for your device under test.
This feature will limit output voltage when excess power is detected through the measurement of current and applied compliance/limit.
However, this does still rely on a measurement being made and a fast change or spike in the output voltage could still occur, depending on test settings/configuration, that would not be prevented entirely.
Our newer instruments, such as Model 2450, utilize a safety interlock. This requires a test fixture or other process to physically ensure an operator cannot come into contact with OSHA designated unsafe voltage levels (greater than 42V or a range that allows sourcing of greater than 42V) while the output is on.
While Model 2400 doesn't have an interlock, it does employ an Output Enable circuit. This is functionally identical, but needs to be enabled in settings (while interlock is required and can't be turned off).
To ensure the safety of your operators at that voltage level, I recommend employing a safety test fixture and output enable.
More information can be found in the User Manual:
https://www.tek.com/en/keithley-source-measure-units/keithley-smu-2400-series-sourcemeter-manual/series-2400-sourcemeter