jeffj@sfsup.UUCP (J.S.Jonas) (07/28/87)
[ker-zap!] I am looking for line cords and the John Meshna catalogue has some interesting offers. Much to my dismay, they don't understand their merchandise, so I ask: "18 AWG 3 cond, SJT, 8', gray" describes a power cord. What is "SJT" ?? Thank you for your very kind attention. Jeffrey Jonas {ihnp4 | allegra} attunix ! jeffj PS: I have a lot on Nixie tubes. I love the way they glow. Dionics makes high voltage drivers to operate plasma panels and nixie displays. Canal Street in NYC was a great place to get them, but no longer. PPS: I still have a magic eye tube that I use as a tester.
larry@kitty.UUCP (Larry Lippman) (07/30/87)
In article <1697@sfsup.UUCP>, jeffj@sfsup.UUCP (J.S.Jonas) writes: > "18 AWG 3 cond, SJT, 8', gray" describes a power cord. > What is "SJT" ?? "SJT" is one of many designations used by Underwriters Laboratories (UL) to decribe the use and insulation catagory of wire and cables. Common power cords made of rubber or plastic all begin with a designation "S". A cord designated "SJ" is a rubber cord rated at 300 volts maximum at a maximum operating temperature of 60 deg C, with an intended application of "light duty service". A cord designated "SJT" is the same as "SJ", except that the insulation is thermoplastic instead of rubber. Most electronic equipment uses cords designated as "SJ" or "SJT". <> Larry Lippman @ Recognition Research Corp., Clarence, New York <> UUCP: {allegra|ames|boulder|decvax|rocksanne|watmath}!sunybcs!kitty!larry <> VOICE: 716/688-1231 {hplabs|ihnp4|mtune|seismo|utzoo}!/ <> FAX: 716/741-9635 {G1,G2,G3 modes} "Have you hugged your cat today?"
gene@cooper.UUCP (Gene from EK Enterprises) (08/03/87)
in article <1697@sfsup.UUCP>, jeffj@sfsup.UUCP (J.S.Jonas) says: > "18 AWG 3 cond, SJT, 8', gray" describes a power cord. > What is "SJT" ?? Well, if memory serves me correctly (no parity errors, etc.), the SJT refers to the plug type: two flat conductors with the semi-rounded ground connector. Air conditioner plugs are different, for example; they have the thicker prongs, with the two flat conductors being colinear instead of parallel ( -.- as opposed to '.'). Oh, well... Gene ...!ihnp4!philabs!phri!cooper!gene "If you think I'll sit around as the world goes by, You're thinkin' like a fool 'cause it's case of do or die. Out there is a fortune waitin' to be had. You think I'll let it go? You're mad! You got another thing comin'!" - Robert John Aurthur Halford
larry@kitty.UUCP (Larry Lippman) (08/11/87)
In article <983@cooper.UUCP>, gene@cooper.UUCP (Gene from EK Enterprises) writes: > > "18 AWG 3 cond, SJT, 8', gray" describes a power cord. > > What is "SJT" ?? > > Well, if memory serves me correctly (no parity errors, etc.), the SJT > refers to the plug type: two flat conductors with the semi-rounded ground > connector. Air conditioner plugs are different, for example; they have the > thicker prongs, with the two flat conductors being colinear instead of > parallel ( -.- as opposed to '.'). Oh, well... Sorry, but this is simply not correct. "SJT", "SO", "SJO", etc. refer to insulation type and rating of power cords, and is a universally accepted designation system used by Underwriters' Laboratories in the U.S. and Canada (CSA agrees). Plug type is another matter. There is NO universally accepted designation system. Plugs and receptacles are specified by current-carrying capacity in amperes and maximum working voltage (like 15 A @ 250 volts). While almost all 10 and 15 ampere @ 125 volt "line" plugs and receptacles are interchangable, this is not true for the many variations of plugs rated for 20 amperes and above, and for 250 volts and above. Different manufacturers (Hubbell, P&S, etc.) use different designs for these higher-current and higher-voltage plugs which are often physically incompatible with those of other manufacturers rated at the same current and voltage. So the point is: plugs (other than 10 and 15 ampere 125 volt line) are generally specified by a manufacturer name and part number. Sometimes obtaining a mating plug or receptacle can be a real trip, especially with Twist-Lock (tm) and similar devices. Some vendors take real delight in equipping their power cords with obscure connectors which the poor end user must mate. A personal example of this is Western Electric; about 12 years ago my organization got a 770 PBX through New York Telephone. This PBX came equipped with an obscure all-metal body Twist-Lock connector, for which we had to furnish a mating receptable. Not only did no local electrical supply firm have the receptacle in stock, but it cost close to one hundred dollars! I asked New York Telephone if we could just cut off their plug and install out own (after all, it was only 120 volts), but of course they said "Nooooooo, this is OUR equipment and you must properly find a mate for OUR plug." I can just imagine some Western Electric engineer in Denver (where the 770 was made) laughing their gonads off every time they thought about a customer having to mate their obscure connector! <> Larry Lippman @ Recognition Research Corp., Clarence, New York <> UUCP: {allegra|ames|boulder|decvax|rutgers|watmath}!sunybcs!kitty!larry <> VOICE: 716/688-1231 {hplabs|ihnp4|mtune|seismo|utzoo}!/ <> FAX: 716/741-9635 {G1,G2,G3 modes} "Have you hugged your cat today?"
dave@onfcanim.UUCP (08/20/87)
In article <983@cooper.UUCP> gene@cooper.UUCP (Gene from EK Enterprises) writes: > >> What is "SJT" ?? > >Well, if memory serves me correctly (no parity errors, etc.), the SJT >refers to the plug type: two flat conductors with the semi-rounded ground >connector. Air conditioner plugs are different, for example; they have the >thicker prongs, with the two flat conductors being colinear instead of >parallel ( -.- as opposed to '.'). Oh, well... No, "SJT" refers to the wire itself. The "S" means "rough Service" - any time I've ever seen this designation, the wire was round, with an outer insulating jacket around the three conductors (also individually insulated). There is also filler material in the space between the conductor and jacket, adding strength and crush resistance. Basically, the wire is intended to withstand some abuse, such as it would receive in an extension cord. The "J" means "Junior" - a smaller version of the cable, that would stand up to less abuse. Compared to an "S" cable, an "SJ" cable may have only half the insulation thickness, and is probably a lot cheaper - that's why you don't see "S" cable very often. Finally, the insulation jacket material is rubber by default. A suffix of "T" means that it is plastic ("Thermoplastic") instead. There are other suffixes too; the only one I can remember at the moment is "O" for "Oil resistant". All of these refer to the wire itself, whether it has anything installed on the ends or not. As for plugs, there are a variety of standard configurations for various voltage and current ratings. We all know what 120V 15A plugs look like in North America. The ones with the flat blades both rotated 90 degrees are for 250V 15A service.