I have a BV bb Q here that i cannot answer, any help appreciated...
It installs in a 1/2 inch KO in panelboard. It is connected to a two pole 20 amp circuit breaker. The service panel is: 200Amp., 120/240V, single phase. There are three conductors on the TVSS, two black and one green. When looking through catalogs I've often seen the same type with two black, one white and one green conductor. I guess my question is: What is the difference if any. Frank
Sparky: IF you are talking "Sentrex" TVSS, by Wiremold, they come in many flavors: 1 phase, 4 wire, 120/240 volt 3 phase, 5 wire (Y & Delta) 1 phase, 3 wire; 120/240 volt 3 phase, 4 wire;120/208Y 3 phase, 4 wire; 277/480 Y
Some have a neutral, some don't; all have grounds,to the best of my knowledge. More info at Wiremold Website (Damn, if I knew how to make a link, and where the "trademark" symbol is; oh well, I'm a 'lectrician, not a computer wiz) John
From the description, it sounds like a 240 VAC 1 Phase 2 wire TVSS device. This would be connected via a 2 pole c/b.
Maybe the Person that posted this Q' could add some Specs from the TVSS device, such as System Voltage.
I am 90% [0.9] sure this would be used on a 200 - 240 VAC 1 Phase 2 Wire type system. Not sure how helpful it would be for 120/240 VAC 1 Phase 3 Wire systems, since there is no connection for the Grounded Noodle Conductor, but that's another story.
p.s. let me know if I guessed correctly, or failed the "Whaddaheck Is This TVSS Device" test.
Scott " 35 " Thompson Just Say NO To Green Eggs And Ham!
Re: TVSS question#15192 10/10/0205:56 AM10/10/0205:56 AM
The number of wires indicate what type of protection you will have.
Line to Line, and Line to Ground - multiple blacks and a green only Line to Neutral(noodle) and Line to Ground - 1 black, 1 white, and 1 green Line to Line, Line(s) to Neutral, Line(s) to Ground - multiple blacks, 1 white, and 1 green
My electrical service is: 120/240V, 3W, single phase, 200 amps. It sounds as if I should of purchased a TVSS with 2 black wires, one white and one green instead of 2 black wires and one green. Actually I grabbed the last one on the shelf at Home Depot. I didn't bother to even look at it until I got home. I assumed all TVSS came with a white (neutral) conductor. The instructions indicated that a 15 amp 2 pole CB was necessary, which I did install. I assume I don't have line to neutal protection.
Frank: IMHO, you do not have line to neutral (120 volt) protection. You have 240 volt, phase to phase protection. You could put it back in the box, & take it back to the orange apron store, like a lot of people do. They usually don't check to careful. It goes back on the shelf, and someone else "gets it". There's a lot of "used" stuff that gets back on the shelves.
Re: TVSS question#15196 10/11/0205:19 AM10/11/0205:19 AM
The TVSS with only three conductors is suitable for use in service equipment as the grounded conductors (neutrals) and the Equipment Grounding Conductors are all attached to the Grounding Electrode Conductor at that point. Since the neutral and EGCs are common in service equipment there is no need for two conductors and two sets of MOVS in the service equipment. In panel that was not service equipment the grounded buss and the grounded conductor buss bar would be separate and one lead to connect each to the TVSS would be needed. -- Tom
"This alternating current stuff is just a fad. It is much too dangerous for general use" Thomas Alva Edison