search  current discussion  categories  kilns & firing - elements 

element calculation...

updated fri 18 jan 08

 

Info khmerceramics on thu 17 jan 08


Hi clayarters,



We want build a small electric test kiln cone 10 with max consumption 15A.
Interior size is ~64 liters (~1.8 cubic feet)

To make the kiln it self (refractory) and electrical connection-regulation
it is OK.BUT>>> We don't have element! We have chrome alumina element (2.5mm
in wire).

Does some one know the diameter of spires and how many spires we must do for
this size of kiln?



Hope you can help us with this.



Actual visiting artist: Martine Vermeulen (NY).

visit www.khmerceramics.com



Serge

Michael Wendt on thu 17 jan 08


For this, you need a volt-ohm- milliamp
meter.
First measure the electrical resistance
in ohms of 2-3 meters of the element wire.
For example: if you read 1 ohm
you can figure the values this way
To get the amperage divide the voltage
by the resistance.
Here 120 volts/1 ohm = 120 amps
You want 15 amps so work backward:
15 * R = 120 (use 240 if you are 240 volts)
R= 120/15 = 8 ohms ( 16 ohms if 240 v)
now all you do is figure how many meters
of resistance wire provides the required
values. Add a little for the double ends
and you can also coil the elements
if they are straight wire by clamping
one end to a long thin rod stuck in a
hand held electric drill a helper pays out
the wire as you slowly rotate the drill,
keeping the coils tight and touching
until the entire length of wire is wound.
Then double the ends where they go through
the kiln walls and stretch the coil carefully
to make it the required length for the
kiln interior, going around two or three times.

Regards,
Michael Wendt
Wendt Pottery
2729 Clearwater Ave.
Lewiston, Id 83501
U.S.A.
208-746-3724
wendtpot@lewiston.com
http://www.wendtpottery.com
http://UniquePorcelainDesigns.com
you asked:
Hi clayarters,



We want build a small electric test kiln cone 10 with
max consumption 15A.
Interior size is ~64 liters (~1.8 cubic feet)

To make the kiln it self (refractory) and electrical
connection-regulation
it is OK.BUT>>> We don't have element! We have chrome
alumina element (2.5mm
in wire).

Does some one know the diameter of spires and how many
spires we must do for
this size of kiln?



Hope you can help us with this.



Actual visiting artist: Martine Vermeulen (NY).

visit www.khmerceramics.com