I had one of those real electrical contractors pull wire and install
disconnects for a 100A system with three SCR phase-angle controllers last
week. The system required single and three-phase feeds. When I arrived on
site, I found the following:

My boxes were wall mounted on uni-strut, side by side. He drilled for
conduit thru the top surfaces of both of these boxes, letting metal chips
fall all over the components mounted in the boxes. It's nice to leave a
'service loop', that is a little extra wire between the conduit entrance and
the top of the main disconnect, right - well, I use door mounted rotary
actuators for these disconnects - and he wrapped the wire around the square
shafts that move whenever the actuators are turned to open the doors. This
is the light stuff, though.

The real winner was discovered late Friday (facing a long=holiday weekend)
when powering up the system. No display at the operator station, lots of
contactors buzzing, but fortunately no smoke, since I powered everything
down right away....

A three-pole disconnect was used on a single phase pull partway across the
plant. In that box, the REAL electrical contractor miswired  one of the "T"
connections to the unused pole. He had them all marked with colored tape
according to code, but he still couldn't get them terminated in all the
right places! The result for this 240V system was the same as when a Neutral
floats on a one-leg system - extreme swings in voltage.

I now have several D.P. contactors with some combination of overvoltage
damaged coils, or metal chips stuck in them that need to be replaced; a PC
with a garbled program in it, and a suspicious customer who just spent
nearly $1M. The entire installation was well done - pleasing in appearance
and functioning properly - except for his botch-job.

The good news is that the three PIC's on the phase-angle boards seem
unaffected since the boards are working perfectly!!!

The bad news is that fixing this system up will cost my company a minimum of
8 hrs @ $150 per, plus travel, plus parts- so the jerk cost us at least
$1500 - not enough to justify a lawsuit, but enough to be irritating. That's
not even to mention the cost of the extended day Friday when about 5 men
worked an additional 5 hours and travelled an average of 2.5 hours to get
home. Several had cell-phones stuck to their ears as their wives and
girlfriends moaned on-and-on about their ruined weekend plans......

The bottom line for this account is this: There are REAL contractors and
there are REAL contractors. Especially when putting a non-standard task
before them, I would always rather hear them say that they need to do some
research before they continue. The ones that go off half-cocked, and always
seem to know everything are the ones that seem to cause problems. I also
keep in mind that I (we PICsters) generally know much more about electron
physics than they do, so I always verify their plans before letting them
loose.

I know you didn't exactly ask, but, if I am not familiar with a contractor
in a certain area I will talk to several before deciding on any one for thr
job. This might be as good an idea as it was to post this to the list in the
first place.

Finally, my biggest gripe, and don't take it personally, please.
Why, or how in the world did you get stuck taking on a job like this one
with a budget that's sooo tight? This has to be the biggest business error
that often translates into technical problems later on.
There are no real shortcuts. Cost is what it is. Anyone who wants the job
for less than what it should cost should be politely told why that's not a
reasonable idea. In these situations, even if you can satisfy the customer,
I find that usually I'm tallying up how much I lost in doing the job the
right way. You can't ever do less, because it is the quality of your work
that will be compromised in the end - along with your reputation and
potential for growth...Also, everyone else that works in the same field
winds up cursing the guy that underbids and accepts lo-ball offers, since
they make it harder for everyone to get work at realistic rates afterward...
Not to worry - I'm sure this isn't you - I just get real nervous when I hear
of anyone working on a job that includes wires and no consumer-type plastic
cases and the budget is low or tight....

Perhaps one day I'll get to tell one of my 'good' stories....
Chris



> > Meeting with a REAL electrical contractor next week to
> review my single
> line
> > diagrams, and discuss the proper way to do things.  I'll
> post what the
> final
> > solution turns out to be...for those who are curious
>
> Just make sure he has not dropped power cords into transformers :)
>
> --
> http://www.piclist.com hint: To leave the PICList
> mailto:piclist-unsubscribe-request@mitvma.mit.edu
>
>

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