Always Check Xformer Before suppling power.

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maintain

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I have run into a a situation with a tranformer this week that I thought I would share. We were lucky to catch this before suppling power.

A journeyman was hooking up a Tranformer (I'll not name MFG) and happen to notice that the leads from the core didn't seem to be in the correct position. The terminal lugs were in the marked position but the straps looked wrong. The X0 bonding terminal was correct but X's and H's seemed reversed.
To Masters verified it was incorrectly wired. Upon contacting Supplier Rep's and Manufacture Rep's the factory (in a nearby country, thank you NAFTA) verified that the wrong terminal board bar was installed at factory.

Does anybody else check the transformer wiring connections upon delivery before shipping truck leaves?


Check. Check. and Recheck.
 
This is also true of fixtures. Many times the manufacturer shipped the fixtures with wrong 120 volt ballasts. If no one checks they all go up in smoke as soon as someone throws on the 277 volt switch.
 
And Switchboards, received a call to check a ground fault tripping, CTs were in the wrong location. had to talk to an application engineer in another country. He told me I did not know what I was talking about. I told him I did and faxed him a drawing, he told me he was an engineer and I was ONLY an electrician. He was right I was wrong, he explained to me that I did not understand GFP and most likely was not testing the system correctly.

I figured why waste my time and told the customer it was their issue as I was not going to argue with support folks. The customer asked me to contact the local rep (again), the local rep asked for support documentation. I had to take pictures and email pics and drawings. Two maybe three weeks later the engineer calls me back, he then told me "oh just move the CTs", no apology. I explained it was his problem and a warranty issue and as I was ONLY an electrician I probably should not move the CT's.
 
maintain said:
Does anybody else check the transformer wiring connections upon delivery before shipping truck leaves?
Click to expand...

Many times - probably most times - large equipment isn't even checked until it's about to terminated....a lot of work goes into rigging the equipment to get it off the truck, moving it to it's location, setting the equipment, running the conduits, etc.

Unfortunately, this is not the time to start looking at it.
 
infinity said:
This is also true of fixtures. Many times the manufacturer shipped the fixtures with wrong 120 volt ballasts. If no one checks they all go up in smoke as soon as someone throws on the 277 volt switch.
Click to expand...
I had a similar problem. Last year I installed some metal halide fixtures at a car dealership...several had the wrong capacitors installed from the factory.
 
maintain said:
I have run into a a situation with a tranformer this week that I thought I would share. We were lucky to catch this before suppling power.

A journeyman was hooking up a Tranformer (I'll not name MFG) and happen to notice that the leads from the core didn't seem to be in the correct position. The terminal lugs were in the marked position but the straps looked wrong. The X0 bonding terminal was correct but X's and H's seemed reversed.
To Masters verified it was incorrectly wired. Upon contacting Supplier Rep's and Manufacture Rep's the factory (in a nearby country, thank you NAFTA) verified that the wrong terminal board bar was installed at factory.

Does anybody else check the transformer wiring connections upon delivery before shipping truck leaves?

Check. Check. and Recheck.
Click to expand...

All connections that are available, whether factory or field made, need to be checked, this should be part of normal start-up and commissioning; and should be considered normal procedure. This may be a job that is subcontracted out to a company that is trained for this purpose (typically large jobs) or by the EC if he feels he is qualified.
 
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