Gee,
You guys have it easy over there!
On this side of the black stump, every electrician that certifies work that entails RCD's (GFI's) is required to test every RCD protected circuit and record the trip time and current on your Certificate of Compliance.
The proper tester for this costs an arm and a leg and maybe some fingers too.
As a quick test though when fault-finding, I use a solenoid type voltage indicator that draws about 240mA when you press the solenoid button on it.
Same here. I paid €1000 for my tester and now I'm probably the only DIYer in the entire country that owns one (at least a new, recently calibrated one). And that was a budget model (though the top-notch one in this class), Flukes and Chauvin-Arnoux go up to €4k. There are €500 models too (or at least were when I bought mine last year) but they usually lack a few essential functions like earth resistance measuring.
I've got a 2-pole voltage tester that draws slightly over 30 mA in load mode (there's also a high-impedance mode that's handy for deciding whether an earth wire is connected at all without tripping the RCD). While not an acceptable tester, it's a farily good indicator that shows if the RCD works more or less like it should, provided it's a 30 mA. 100 mA and up don't trip at all and 10 mA are tested at well beyond their nominal fault current, so you can't really say whether they work properly.
