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cress kiln: ground wire question

updated sat 15 nov 03

 

Stephani Stephenson on thu 13 nov 03


Hi all
am calling Arturo at cress tomorrow but will ask the group tonight!

got the old Cress C8H back together nicely w/ regard to elements, ITC,
brick repair, element pins, kilnsitter, etc.
fired empty to about cone 06
noticed lower element didn't heat
checked elements with continuity meter, though will take Arnold's good
advice and see if I can figure out how to use
a multimeter or ohmmeter, but in the mean time

fired again, this time all 3 lower elements not heating well
kiln taking way too long
Will check switches when it cools, downloaded a wiring diagram, noticed
these 3 are connected
BUT, my main question for the collective wisdom of this internet
community IS

in retrospect I made a bonehead oversight
I kept track of all wires just fine except I cannot remember where EXACTLY
the GROUND wire connects....in this case it is a big exposed wire firmly
screwed into to a terminal/block
with a hole in it. I did not mess with any of the other main wires, so
they have always remained connected.

does it BOLT to the inside of the FACEPLATE of the wiring box,
or does it SCREW into the KILN itself via the BACK SIDE of the wiring
box and via the hole which holds the box onto the Kiln.... or does it
matter?

This box came off in a hurry right after I removed the switchbox cover.
I did kept all bolts and screws that came out in a little dish, but
there may have intermixed some . Also many of the exterior screws were
corroded so replaced with new ones

I did not have a bolt in the box though, and it seems like a bolt and
washer would definitely be needed to hold the groundwire onto the
faceplate,(as all the screws were too small to connect it to the face
plate by themselves),
so I screwed the ground wire and groundwire terminal it into a
corresponding hole in the CENTER BACK of the box. this same screw
attaches the entire box in place onto the kiln itself.
However I have this nagging feeling that something was attached via
that extra hole in the lower right side of the faceplate.
Though the kiln seemed to be connected OK, I can't help wondering if an
improper ground is partly responsible for lack of heating.... also does
it matter what TYPE of bolt or screw I use...i.e , zinc plated, brass,
etc....

finally I have ordered a couple of extra switches and new 'switch to
element' wires as well. just to narrow down the
possible contributors to the problem. just wondering if I somehow
destroyed the switches by faulty installation...or just hoping when I
take it apart again I find a nice loose wire,easily found and replaced...
Want to thank CLAYARTS's Arnold at Paragon, Cindi at bigceramicstore and
Dave Finkelburg for some very helpful pointers about old kilns, amps,
elements , etc.

sign me
'longing for a nice normal firing again as the orders are piling up, but
knowing maintenance and repair is part of the ball gameso I am bringing
the kiln chocolates and flowers every day!"

Stephani Stephenson
steph@alchemiestudio.com

wayneinkeywest on fri 14 nov 03


Stephani:
The ground wire should have a place of attachment that is free from rust and
paint, so that it makes a good contact. You might be able to tell where it
goes just by the length of it. I suspect you have other issues, though, for
were your ground not conducting as it should you would likely get nothing at
all from the kiln.

The heck with the chocolates and flowers. That's for lovers!
Bring it a bowl of chicken soup! That's for repair...just ask any
grandmother:>)
Best Regards,
Wayne Seidl

> sign me
> 'longing for a nice normal firing again as the orders are piling up, but
> knowing maintenance and repair is part of the ball gameso I am bringing
> the kiln chocolates and flowers every day!"

Carl Finch on fri 14 nov 03


At 10:04 AM 11/14/03 -0500, wayneinkeywest wrote:

>Stephani:
>The ground wire should have a place of attachment that is free from rust and
>paint, so that it makes a good contact. You might be able to tell where it
>goes just by the length of it.

Yes, she might, but she better find the right connection point! The
correct point of attachment is very important--it is one which ties
together all the normally non-conducting metal parts of the kiln (frame,
control housing, sheet metal, etc.).

>I suspect you have other issues, though, for
>were your ground not conducting as it should you would likely get nothing at
>all from the kiln.

No. The ground wire is a safety feature and has no functional purpose
relative to firing. It should be carrying current ONLY in the case of an
electrical malfunction. It's purpose in that case is to protect Stephani
from carrying that current!

But certainly if some of her elements are not heating, she does have other
issues.

--Carl
in Medford, Oregon

Steve Slatin on fri 14 nov 03


Wayne --

I'd think she'd still get power if everything else were functioning --
but
she'd be running a pretty big shock hazard. I'd hazard a guess that her
240 circuit is made of what was (at the panel or fusebox) two 120 'hot'
lines, a neutral and a ground. The circuit is 'live' without a
functioning ground, but it's a heap more dangerous.

Finding the grounding spot by the length of the original wire is a good
idea; it is of course important to make sure you have a good solid
connection at that point before tying the ground into it again --
sometimes there's dirt or corrosion or whatever that interferes with a
good connection. Some people use copper scrubbers or something similar
to make sure the metal's 'bright' before reattaching.

-- Steve (nothing interesting to say here) Slatin

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of
wayneinkeywest
Sent: Friday, November 14, 2003 7:05 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Cress Kiln: ground wire question

Stephani:
The ground wire should have a place of attachment that is free from rust
and
paint, so that it makes a good contact. You might be able to tell where
it
goes just by the length of it. I suspect you have other issues, though,
for
were your ground not conducting as it should you would likely get
nothing at
all from the kiln.