Longtin, Jeff on wed 30 jul 03
Gang,
A few thoughts on kilns and Milla's tragic situation.
First and foremost, I think we can all agree that what happened to Milla is
a true tragedy. It's the thing potters fear most and its the thing that
breaks our heart when we here its happened to someone we know. I hope the
best for you Milla!
On kilns and plugs: I don't know for certain but I think plugs became
popular as a safety feature to counter the improper install of hard wired
kilns. While hard wiring a kiln properly is arguably safer than a plug, an
unsafe/improper hard wire is not.
Back in the 80's I moved into a building that had six potters in it. When I
had a licensed electrician wire my kiln he was blown away to see that the
wiring for the other kilns had only been wired with two leads without wire
grounds. They call it "conduit ground". In theory you're alright (safe) as
long as the conduit line remains intact. However, if the conduit line should
break, or the fittings become loose, the grounding capability may become
impaired. If this happens you run the risk of being electrocuted by your
kilns metal jacket.
It is for this reason that a 3 wire install is code.
The plug, while it may create problems much like Milla's, it also solves the
problem of a non-ground wire install. (That third prong serves to ground
your kiln so you won't electrocute yourself!)
Life is short comment:
Two months ago I was in a rear end collision and have been seeing a
chiropracter since. Two weeks ago I made a stupid mistake and caused about
2k in damage to my car and anothers, but no was was even remotely hurt. In
the last two weeks, however, I have been informed of friends of friends,
who, in two seperate accidents, through no fault of their own, were killed
in head-on collisions.
Life is just too damn short.
Jeff Longtin
in sunny minneapolis
hoping we all slow down and take it easy
realizing people are just too reckless these days
psci_kw on wed 30 jul 03
----- Original Message -----
From: "Longtin, Jeff"
To:
Sent: Wednesday, July 30, 2003 12:24 PM
Subject: Kilns/Plugs/Hardwiring/Life is short
snip
> It is for this reason that a 3 wire install is code.
> The plug, while it may create problems much like Milla's, it also solves
the
> problem of a non-ground wire install. (That third prong serves to ground
> your kiln so you won't electrocute yourself!)
Jeff, not to pick nits, but a four wire install is now code for 220-240vac
in the US
....2 hot legs of 120v, a neutral and a ground. If the kiln has a three
wire plug
attached to it, the fourth wire (the ground) in the electrical box on the
wall
will probably just be attached to the box, as it's still common in many
parts of
the country to tie the neutral to the ground in the (circuit breaker) panel.
As time goes on, more and more of us will end up hard wiring our kilns
direct to the box
and we can have the ground attached at that point to the case on the kiln
controller.
After all...how often do you move your kiln from room to room?
Wayne in KW
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