GW Instek GPT-9603 Withstanding Voltage/Insulation Resistance Tester, 100VA AC/DC Test Capacity

I bought this unit almost two years ago and finally found a project that really needed it to help track down failures in wiring insulation in a product. The controls are reasonably intuitive, I was able to figure it out without looking at a manual.It supports both AC and DC testing, though I didn't find a way to reverse the polarity other than reversing the two leads for negative DC tests. When the current limit is exceeded during a test, it immediately shuts down the output and indicates the failure with sound, LEDs, and text on the display.If you're buying one you probably already know that the voltages generated by this instrument are EXTREMELY DANGEROUS and it should be used with extreme care and safety precautions. Read the safety warnings even if you don't read the manual and never touch any part of the wiring or the device under test during or immediately after a test.Most of the models in this family support high voltage and low current measurements and can read out the result in MegOhms if desired. The 9603 model also includes ground bond resistance measurements.Overall a great piece of test equipment and a good value for the money.