In theory the current limit is important, as you can get a false positive if the HV tester does not have enough grunt.
What happens is the the insulation normally does not break down instantly, there may be partial breakdowns prior to the final complete failure. If the HV tester does not have enough current, then during partial breakdown the voltage drops down due to the current limit, and the insulation recovers, and never fully breaks down. A tester with a high current limit (e.g. 100mA) does not exhibit this problem.
As I said before, the quality of modern insulation (used within specifications and not damaged by a fault test) is so high that this is very much theoretical matter. But of course, special cases always apply. A test lab should do routinely do tests with 100mA equipment; a manufacturer though should be OK for 10mA (or 5mA), or as needed for the EMC capacitors.
What happens is the the insulation normally does not break down instantly, there may be partial breakdowns prior to the final complete failure. If the HV tester does not have enough current, then during partial breakdown the voltage drops down due to the current limit, and the insulation recovers, and never fully breaks down. A tester with a high current limit (e.g. 100mA) does not exhibit this problem.
As I said before, the quality of modern insulation (used within specifications and not damaged by a fault test) is so high that this is very much theoretical matter. But of course, special cases always apply. A test lab should do routinely do tests with 100mA equipment; a manufacturer though should be OK for 10mA (or 5mA), or as needed for the EMC capacitors.