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#66708 - 06/14/06 06:42 PM R, S, T ???
master66 Offline
Registered: 04/18/02
Posts: 260
Loc: Masontown, PA, USA
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.
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#66709 - 06/14/06 06:51 PM Re: R, S, T ???
Larry Fine Offline
Registered: 02/18/05
Posts: 684
Loc: Richmond, VA

*Read The Manual
Larry Fine
Fine Electric Co.
#66710 - 06/14/06 08:53 PM Re: R, S, T ???
e57 Offline
Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
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'.....
Mark Heller
"Well - I oughta....." -Jackie Gleason
#66711 - 06/14/06 09:42 PM Re: R, S, T ???
Trumpy Offline

Registered: 07/05/02
Posts: 8560
Loc: SI,New Zealand
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?.
Let's face it, these days if you're not young, you're old - Red Green grin
#66712 - 06/14/06 11:22 PM Re: R, S, T ???
e57 Offline
Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
Reminds me of that guy who wired a cord cap XYN, when it was suppossed to be XYZ.
Mark Heller
"Well - I oughta....." -Jackie Gleason
#66713 - 06/15/06 02:39 AM Re: R, S, T ???
Texas_Ranger Offline
Registered: 12/17/01
Posts: 2351
Loc: Vienna, Austria
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...
#66714 - 06/15/06 05:46 AM Re: R, S, T ???
pauluk Offline
Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
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.
#66715 - 06/16/06 01:23 PM Re: R, S, T ???
Fred Offline
Registered: 04/30/01
Posts: 461
Loc: Straughn, IN 47387
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.
#66716 - 06/16/06 03:10 PM Re: R, S, T ???
Scott35 Offline

Broom Pusher and
Registered: 10/19/00
Posts: 2724
Loc: Anaheim, CA. USA
Larry Fine:



*Read The Manual


I remember it as:

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

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
#66717 - 06/16/06 04:30 PM Re: R, S, T ???
Registered: 12/08/05
Posts: 865
Loc: Titirangi, Akld, New Zealand
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
The product of rotation, excitation and flux produces electricty.
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