If you want to check the electrical specs of the purge, I would just Ohm the windings . The ECU spec for a good purge is a current draw of .2-.3 Amps, so that equates to a purge valve coil resistance value of 40-60 ohms. That would be the simplest way to check it.
Most purge faults are dirt and crud from the canister and simply need a cleaning, but if the problem is electrical, the first test I would do is OHMS verification at the Valve with plug removed.
The purge is a frequency based signal and is dependant on engine load factors determined by ecu sensor inputs..the freq is from 5 to 20 Htz, so the R value of the purge has to be in spec for ECU sig to exist.

__________________
A Dalton