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  1. #11

    Cool Secondary?

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    When I started doing line work(1965) we never grounded secondaries, I still wouldn't today. I Changed companies in 1982 ,Florida power Corp. and they required secondaries to be grounded.Had a Lineman open a CSP Transformer switch and put a ground on without testing,he got a face full of fire. Never trust a CSP Transformer switch!
    Grumpy

  2. #12

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    Quote Originally Posted by jerry View Post
    When I started doing line work(1965) we never grounded secondaries, I still wouldn't today. I Changed companies in 1982 ,Florida power Corp. and they required secondaries to be grounded.Had a Lineman open a CSP Transformer switch and put a ground on without testing,he got a face full of fire. Never trust a CSP Transformer switch!
    My company doesn't ground secondary either. something to do with amp ratings on the grounds. I always just figured even if secondaries were grounded and some how became energized the transformer would just see the grounds as load, and well burn baby burn.

  3. #13

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    I more or less was thinking of backfeed....oh well.

  4. #14
    Join Date
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    I worked at one place that required you to disconnect the secondary leads when working on or near an isolated transformer, grounding the secondaries was acceptable too. Some years ago I was on a project to change out elbows and inserts on padmount transformers. After isolating and grounding the primary we would ground the secondary to prevent backfeed, it saved a fair bit of time . We made a ground from a set of jumper cables, were we could clip onto the secondary lugs and ground to the system neutral

  5. #15

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    For years the safety book said you have to use co approved grounds in order to grd. The problem was we never had co approved secondary grds a lot of homemade stuff like jumper cables and the like but if any of you have seen a video on fault current you know that type of clamp is inadequate . In the last five or ten years we locally developed in the underground putting a Chance ball and socket grd stud in new installations on three phase pads and each truck has a set of grounds of the socket grounds so you get a good tight connection that won't blow off in case of mistaken energising, Still don't have co approved overhead secondary grds, of course the professional smart guys just tell us to use our regular grounds on open wire or triplex secondaries. I do remember one of the old timers used to say all you need for a secondary grd when doing a cutover [ 4800 delta to 23kv wye] was to lay your klien wrench across the secondary bushings.

  6. #16

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    Quote Originally Posted by bluestreak View Post
    For years the safety book said you have to use co approved grounds in order to grd. The problem was we never had co approved secondary grds a lot of homemade stuff like jumper cables and the like but if any of you have seen a video on fault current you know that type of clamp is inadequate . In the last five or ten years we locally developed in the underground putting a Chance ball and socket grd stud in new installations on three phase pads and each truck has a set of grounds of the socket grounds so you get a good tight connection that won't blow off in case of mistaken energising, Still don't have co approved overhead secondary grds, of course the professional smart guys just tell us to use our regular grounds on open wire or triplex secondaries. I do remember one of the old timers used to say all you need for a secondary grd when doing a cutover [ 4800 delta to 23kv wye] was to lay your klien wrench across the secondary bushings.
    bluestreak,you brought back a memory,I have also seen that...a guy climbs a pole with a transformer on it and takes his cresent wrench off his belt and lays it over the bushings....its grounded....takes the wrench off and begins working.....yeap,seen that.

  7. #17

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    Also have pulled up on down wires mostly where the pea-vine is on the street/front easement and had customers wanting to roll up downed wire,or touch it before we have a chance to ground it....One such customer happened to be a high school principle that put the paddle to me more than once as a teen...you would think he would know better....it was my turn to give him the class.

  8. #18
    Join Date
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    Ontario, Canada
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    Yeah the jumper cable thing wasn't meant to prevent accidentally energizing a can, just to prove the secondaries were isolated. Nothing in our rule book to require secondary grounds. My theory is at least you did something to mininze the hazard.

  9. #19

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    I'll be the second guys to admit placing the ground end of the jumper on a neutral with leather gloves. It's the neutral. It's ground potential. It does carry current, but that's why you don't open it, it's not why you can't touch it without rubber gloves.
    Our neutrals were clamped to the pole and not insulated on a spool insulator. We wanted them grounded as best we could. The neutral was at the same potential as the pole we were standing on. Doesn't make much sense to put rubber gloves on your hands when your feet are around the ground wire attached to the neutral.

    Do you use primary rubber gloves to attach a house service neutral conductor to the system neutral? Then do you take off the primary gloves and put on secondary gloves to attach the 120v phases?
    Do you wear gloves to install a staple on a ground wire? It's attached to the neutral, so is it treated the same?
    What is the problem using leather gloves to attach one end of a ground jumper to the neutral with the other end isolated and probably across your belt or lying in the bucket next to your uncovered leg? Then...you use a hot stick to ground the object (that was previously energized) being grounded.

  10. #20
    Join Date
    Jun 2011
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    Quote Originally Posted by copperlineman View Post
    I'll be the second guys to admit placing the ground end of the jumper on a neutral with leather gloves. It's the neutral. It's ground potential. It does carry current, but that's why you don't open it, it's not why you can't touch it without rubber gloves.
    Our neutrals were clamped to the pole and not insulated on a spool insulator. We wanted them grounded as best we could. The neutral was at the same potential as the pole we were standing on. Doesn't make much sense to put rubber gloves on your hands when your feet are around the ground wire attached to the neutral.

    Do you use primary rubber gloves to attach a house service neutral conductor to the system neutral? Then do you take off the primary gloves and put on secondary gloves to attach the 120v phases?
    Do you wear gloves to install a staple on a ground wire? It's attached to the neutral, so is it treated the same?
    What is the problem using leather gloves to attach one end of a ground jumper to the neutral with the other end isolated and probably across your belt or lying in the bucket next to your uncovered leg? Then...you use a hot stick to ground the object (that was previously energized) being grounded.

    good point copperLM.... i never heard this rule until reading about it on this website...that said, i have encountered poorly grounded neutrals that buzz like crazy to the leathers.... just gotta stay isolated from another potential like a pole ground.

    next time i see this im gonna get a voltage reading from the neut to a pole ground to see what is actually there.

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