I bought a new meter today that has rotation indication. I've had them before but never knew what the letters R, S & T stand for. I know the phases by A, B & C.

R.T.F.M.*


*Read The Manual

ABC = RST just a different set of letters for a sequence, I'll make the assumption that this is a Hotek or Hioki meter? And will also assume that the leads are red-white-blue, instead of black-red-blue?

Japanese made? Nothing wrong with that, I believe it will have the international symbol for clock-wise, of an arrow going 'clock-wise'.....

I believe that RST is a European convention,
they also used to use UVW as well.
I don't know a whole lot about the origins, maybe someone like Pauluk can clarify this?.

Reminds me of that guy who wired a cord cap XYN, when it was suppossed to be XYZ.

That's old European designation. I believe the terminals of a motor leading directly to the windings were/are XYZ, the terminals fot the feeder are UVW, and going backwards in the alphabet, the terminals inside receptacles et cetera were named RST. Has been L1, L2 and L3 for some 20 years though, at least in Continental Europe. My school (built in 1975-1980) still has the old designations written everywhere. After all, it still has fuses instead of breakers too...

Yep, I remember seeing the RST designations on some older European equipment years ago. We never used that scheme in Britain: Everything was either A/B/C, L1/L2/L3, or R/Y/B, the latter being for our standard phase colors: red/yellow/blue.

Check out an Ideal 61-521 phase rotation meter. Red, yellow and blue phase indicator lights are also marked R, S, T. I never did know what RST stood for.

Larry Fine:


LOL!!!

I remember it as:

"Read The Fu.... er... Funny,... ya that's it Manual.

Scott35

R, S, T are the older European indications for 3 Phase equipment.

RST are the 3Ø supply phases.
UVW is start, for star delta motor starting.
XYZ is run for polyphase motors.

Now been superseaded with L1, l2, L3

Want to be confused?

Ideal has come out with a combo rotation tester and motor rotation tester.

On one side of the tester R,S,T, on the other L1,L2,L3.

Why can't it be labled the same?
http://www.idealindustries.com/tm/SpecialtyTestEquipment.nsf