Sentry Xpress 5 Cone-Fire / Ramp-Hold
20
Do not leave your kiln unattended during operation.
After you have set up the
[KW]
and
[CENT]
options, you
can check the progressive cost of a firing while the kiln is on,
and you can check the total cost after the kiln fires to com-
pletion.
1
While the kiln is firing, or from
[IDLE]
, press the
Up Arrow
key repeatedly until
[COST]
appears.
Press
Start/Stop
.
2
The cost of the firing will appear.
3
Press
Start/Stop
to return to the normal display.
Note:
If you enter the kiln wattage in the
[KW]
op-
tion but you do not enter cost per kilowatt-hour in
the
[CENT]
option, the controller will display kilo-
watt-hours instead of the firing cost.
Note:
By checking the
[COST]
option during a fir-
ing, you can see how much the cost increases as the
firing progresses.
Pointer:
If you wonder how much Slow Cooling
adds to the cost of a firing, check the
[COST]
op-
tion before Slow Cooling begins, and check it again
after the kiln has fired to completion.
TCOS / Thermocouple Offset
Calibrate the Thermocouple(s)
The thermocouple is the rod extending into the firing
chamber. The thermocouple measures the temperature.
K-Type thermocouples can “drift” as they age, causing a
gradual shift in temperature readings. Thermocouple Off-
set calibrates the controller to compensate for drift.
Note:
The thermocouple must protrude into the
firing chamber the correct distance: about ¾” for
¼” wide thermocouples, ½” - 5/8” for 1/8” wide
thermocouples.
How to Set Thermocouple Offset
You can enter a temperature change up to 45°F/25°C
higher or lower than the zero factory setting.
1
From
[IDLE]
, press the
Up Arrow
repeatedly un-
til
[TCOS]
appears.
Note:
With each
Up Arrow
key press, you will see
the next option. When you see
[EXIT]
, press the
Up Arrow
again to see more options. When
[OPT2]
appears, press
Start/Stop
. That will take
you to more options.
2
When you see
[TCOS]
press the
Start/Stop
key.
The current Thermocouple Offset adjustment
number will appear.
3
Using the arrow keys, select a new adjustment
number (see chart, next column). Then press the
Start/Stop
key.
[IDLE]
will appear.
4
From
[IDLE]
, press the
Up Arrow
repeatedly un-
til
[TCOS]
appears.
5
Press
Start/Stop
.
[
O]
, or a Thermocouple Off-
set, will appear.
6
Using the arrow keys, enter the new offset. Press
Start/Stop
.
[IDLE]
will appear.
Thermocouple Offset Settings
°F Setting °C Setting
Result
0
0
No adjustment
H 1-45
H 1-25
Kiln will fire hotter
C 1-45
C 1-25
Kiln will fire cooler
Thermocouple Offset Examples
Setting
Result
H 1
Kiln will fire 1° hotter
H 17
Kiln will fire 17° hotter
C 12
Kiln will fire 12° cooler
TEDE / Temperature Deviation
Adjust Temperature Sensitivity of Error Codes
The temperature that the controller is trying to reach, at
any given time, is called the set point. During heating or
cooling, the set point changes at the rate you programmed.
During a hold, the set point remains steady.
The Sentry Xpress shows error messages when it can’t
maintain the set point temperature. The cushion, or lee-
way, allowed before an error message flashes is called Tem-
perature Deviation. When the temperature in the kiln is off
target by more than the Temperature Deviation setting, the
alarm sounds. Temperature Deviation affects these error
messages (see page 25):
[FTH]
Fail to Heat
[FTC]
Fail to Cool
[LTDE]
Low Temperature Deviation
Some people worry when
[FTH]
,
[FTC]
or
[LTDE]
ap-
pears. They wonder if something is wrong with the kiln
when in many cases there isn’t. Here are four ways to stop
the alarm messages from appearing during routine firings:
Method 1:
Test your kiln to find its fastest firing rate
and its slowest cooling rate. Then program the controller
using rates within the range of the kiln’s heating/cooling ca-
pacity. Example: If your fastest heating rate is 600° per
hour, enter a rate no faster than 600°.
Method 2:
Set the deviation temperature to a higher
number in the
[TEDE]
option. The higher the number, the
less likely that an alarm message will appear.
Method 3:
Set the deviation temperature to 0 in the
[TEDE]
option. This turns off the
[FTH]
,
[FTC]
and
[LTDE]
alarms (page 25). We ordinarily do not recom-
mend a 0 setting.
Method 4:
Program a segment at FULL rate (9999°).
This will shut off the deviation alarms for that segment.
(However, deviation alarms will continue to work during
the hold and all other segments with slower rates.)
