Rio Grande Sentry Express User manual

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y.
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Sentry Express Digital Temperature Controller
Temperature Display
No Display Dot: Temperature
display in °F.
Right-Hand Display Dot:
Temperature display is in °C. See
page 7 for instructions on select-
ing °F or °C.
START/STOP Key
1) On/O : Starts and
stops a  ring.
2) Enter Data: Press after
each programming step. It
works like the Enter key on
a computer.
Down Arrow Key
1) Lowers Numbers
2) Reviews a Program:
From IdLE or during  ring,
press Down Arrow. The
program you have selected
will appear one step at a
time.
3) Delays a Firing: From
Strt press Down Arrow.
°F
°C
°C Display Dot
Time Display
Center Display Dot: Sepa-
rates hours from minutes.
Example: Display shown above is
1 hour and 30 minutes.
Indicator
Lights
Top: On during
programming.
Middle: On
during program
review.
Bottom: Blinks
during  ring.
Up Arrow Key
1) Raises Numbers
2) Select a Firing Mode:
From IdLE press START.
Press Up Arrow to select
Single-Speed or Ramp-
Hold.
3) Skips a Segment:
During a Ramp-Hold  ring,
skips to next segment.
After pressing the Up
Arrow, SStP will appear. To
skip, press Up Arrow again.
Courtesy of:
Paragon Industries, L.P.

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Contents
General Guidelines .....................................................3
Time and Temperature Display .....................................................3
Operation Begins from the IdLE Display ....................................3
Thermocouple Inspection ..............................................................3
A Rapid Way to Scroll Numbers ....................................................3
Program Review & Repeat Firing ..................................................3
Delay .......................................................................................................3
Power Failures .....................................................................................4
CPLT Message: Firing Completed .................................................4
Thunder Storms and Power Surges .............................................4
Theory of Operation ...................................................4
Rate .........................................................................................................4
Hold.........................................................................................................5
Two Firing Modes: Single Segment and Ramp-Hold ............5
Single Segment Programming Instructions .............................5
Temperature Over-Shoot ................................................................6
Ramp-Hold Mode .......................................................6
Repeat Firings ......................................................................................6
Programming a Cooling Segment ...............................................6
A Ramp-Hold Practice Program ....................................................7
Skipping a Segment in a Ramp-Hold Program .......................7
Ramp-Hold Programming Instructions......................................7
Lost Wax Burnout .......................................................8
Overview ...............................................................................................8
A Sample Program .............................................................................8
Burnout Instructions .........................................................................8
Error Messages............................................................9
bAdP/Bad Programming .................................................................9
EtH/Electronics Too Hot ...................................................................9
FaIL/Thermocouple Failure .............................................................9
TCR/Thermocouple Reversed ........................................................9
FtL/Firing Too Long ...........................................................................9
PF 1/Power Failure .............................................................................9
PF 2/Power Failure .............................................................................9
tC/Thermocouple Failure ................................................................9
Selecting °F or °C Display ...........................................9
Display Messages .................................................... 10
Trouble Shooter ....................................................... 10
Problem: Controller display is blank. No heat in kiln ......... 10
Problem: Controller display turns on. No heat in kiln ........ 11
Problem: Kiln switch box ½ amp fuses keep blowing ....... 11
Safety
The warranty on your Sentry Xpress controller
does not cover damage from overring, regard-
less of the circumstances. It is the operator’s
responsibility to make sure the kiln turns o at
the proper time.
• When the kiln is not in use, disconnect the
power.
• Do not leave the kiln unattended, especially near
the expected shut-o time.
• Wear ring safety glasses when looking into the
ring chamber of a hot kiln.
• Do not touch hot sides of kiln. Keep unsuper-
vised children away.
• Install your kiln at least 12 inches from any wall
or combustible surface.
• Do not open lid or door until kiln has cooled and
all switches are o.
• Fire only in a well-ventilated, covered and pro-
tected area away from combustible materials.
• Keep cordset away from hot sides of kiln or fur-
nace.
• DANGEROUS VOLTAGE! Do not touch heating
elements with anything. Disconnect before ser-
vicing.
©2004, by Paragon Industries, L.P. IM-221/10-04

General Guidelines
Time and Temperature Display
Center Dot: Time
A center dot appears during
time display. It separates hours
from minutes (i.e. 1 hour, 30
minutes displays as 01.30).
During temperature display, the
dot disappears.
Right-Hand Dot: °C
When temperature is dis-
played in °C, a dot appears in
the lower right. In °F display,
it disappears. You can choose
between Fahrenheit and
Celsius display. See page 9.
Operation Begins from the IdLE Display
IdLE must appear before you can  re the kiln
 If CPLt, STOP, or other message appears instead of
IdLE when the kiln is  rst turned on, press the START/
STOP key (the key with the circular arrow). IdLE will
appear.
 If you press the START/STOP during a  ring, STOP
will appear. To get back to IdLE, press START/STOP
again.
 If the display shows an error message such as FaIL
instead of IdLE, see page 9.
 CPLt ( ring completed ) appears at the end of a
 ring. To make IdLE appear, press START/STOP.
Thermocouple Inspection
The small rod protruding into the firing chamber is the
temperature sensor, or thermocouple.
CAUTION: Bumping the thermocouple can push it out
of the firing chamber. This could cause an overfire! The
controller does not contain an alarm to detect this type
of failure. Bumping the thermocouple could also cause
inaccurate readings.
 A ⅛” thermocouple should extend into the firing
chamber ½” - ⁄”.
 A ¼” thermocouple should extend into the firing
chamber ¾” - 1” or more.
 Keep shelves, posts and ware 1” - 1½” away from the
thermocouple.
A Rapid Way to Scroll Numbers
During programming, hold an arrow key down several
second, and the numbers will begin to scroll rapidly.
Ordinarily, you would press Up Arrow to raise a number
and Down Arrow to lower it. But sometimes it is faster
to press the opposite key. This is because the numbers
scroll below 0000 to the highest number, and vice versa.
Examples:
 To program a 99.59 hour Hold when the display
shows 00.00, press the Down Arrow once.
 To program a FULL rate when the display shows 0000,
press the Down Arrow once.
 To program a temperature of 200°F when the display
shows 1800°F, press the Up Arrow. That is faster than
pressing the Down Arrow.
Program Review & Repeat Firing
Program Review lets you check that the information
programmed into the controller is correct. It is a good
habit to use Program Review before every firing. Program
Review shows the values for the program in active
memory, which is either—
The program that was fired last.
The program that was selected since the last firing.
 Program Review during firing: Press the Down
Arrow key. The rate, temperature, hold, etc. will dis-
play one after the other. Firing will continue.
 Program Review from IdLE: Press the Down Arrow
key. After rate, temperature, hold, etc., Strt will
appear. Press START/STOP. -On- will appear, and the
kiln will begin  ring the program just reviewed.
Delay
Delay is a count-down timer. The kiln begins firing
when the timer runs out of time. Use Delay to fit a firing
into your schedule.
CAUTION: For safety, do not leave the kiln alone during
the delay or a firing. We cannot guarantee your kiln
against overfiring even though the controller is auto-
matic.
1. After you have entered a program and the controller
is ready to begin firing, Strt will appear.
2. Press the Down Arrow key once. dELA will appear,
alternating with 00.00.
3. Use the arrow keys to enter delay time. (The decimal
separates hours and minutes. Example: 1 hour and
10 minutes = 01.10. Then press START. dELA will
appear, alternating with time left until the firing
begins.
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°F
°C
The center display dot
indicates time instead of
temperature.

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Power Failures
After a power failure, the controller will con-
tinue firing provided that:
 The kiln temperature is above 212°F/100°C when the
power comes back on.
 The temperature dropped no more than 180°F/100°C
while the power was off.
Power Failure Messages
PF 1 The power failed during firing, and tempera-
ture dropped more than 180°F/100°C.
PF 2 The power failed during firing, and kiln tem-
perature was below 212°F/100°C when the power came
back on.
CPLT Message: Firing Completed
When the firing has success-
fully completed, the Sentry
Xpress will shut off power to
the elements. Then three mes-
sages will cycle one after the other:
1. CPLT (complete)
2. Firing time in hours and minutes
3. The current kiln temperature
Thunder Storms and Power Surges
Unplug the kiln or disconnect the power when the
kiln is not in use, especially during thunder storms and
in areas with frequent power surges. If the kiln is part
way through a firing when a storm begins, it is probably
okay to continue the firing with close supervision. Do
no leave the kiln unattended.
Theory of Operation
The temperature you are firing to is called the target
temperature. After the controller reaches the target
temperature, it can also hold that temperature.
The controller fires at a controlled heating rate. The
rate is figured in degrees per hour. If you selected a rate
of 100° per hour, it would take 10 hours for the kiln to
reach 1000°. Rate is similar to “miles per hour.”
In summary, the controller does three basic tasks:
1) It fires at a controlled heating rate, or speed, mea-
sured in degrees of temperature change per hour.
2) It fires to a target temperature.
3) It can hold the target temperature.
The controller fires in segments, or stages. A segment
is a given heating rate to a target temperature. Shown
above is a segment with a rate of 625°, a target tem-
perature of 1250°, and a hold of one hour.
Heating rate is figured in degrees per hour. The rec-
ommended heating rate for the material you are firing
is usually available from your supplier. It also varies
depending on the thickness of the material.
To figure how long a firing segment will take, subtract
the current temperature from the target temperature
and divide the resultant temperature by the heating
rate. In the diagram above, the firing time is 1250° - 80°
(room temperature) = 1170 ÷ 625 = 1.87 hours.
The controller can fire up to 8 segments pre firing.
One segment is often all that is needed, though.
After the controller has finished firing the last seg-
ment, it will turn off power to the elements.
Rate
Each segment must include a rate, which is degrees
of temperature change per hour.
The kiln will fire at full power when the rate is
1799°F/999°C. Full power displays as FULL.
Note: To enter full power from 0000, press the Down
Arrow key once.
CPLT Message: Firing Completed
Parts of a Segment
500°
1500°
2000°
1000°
21 3 4
Ramp
Hold
“Ramp” means to
raise or lower the
temperature.
“Hold” means to
maintain a
temperature.
This segment will reach the target temperature of 1250° in 2 hours, then
hold that temperature for 1 hour.
Rate = Firing Speed
500°
1500°
2000°
1000°
21 3 4
Rate = 1000° per hour
Rate = 500° per hour
Rate = 333° per hour
Hours
Rate is  gured in degrees per hour

Hold
Hold maintains a steady temperature for the length of
time you specify. You can use Hold in both heating up or
cooling down segments.
When Hold is set to 99.59 hours, the controller will
remain at that temperature indefinitely, until you press
STOP. To enter 99.59 hour Hold, press the Down Arrow
once from 00.00 during programming.
Note: During firing, the display shows Hold temperature
and time left in Hold.
Two Firing Modes: Single
Segment and Ramp-Hold
To give you greater flexibility, your controller has two
firing modes:
Single Segment Mode (see next column)
Often times, all you will need is one segment that
includes rate (temperature change per hour), a target
temperature, and (if needed) hold time.
In Single Segment mode, you can choose one of five
firing speeds. Then enter the temperature you are firing
to.
Ramp-Hold Mold (see page 7)
Ramp-Hold mode offers much greater flexibility than
Single Segment mode. Use Ramp-Hold to create a cus-
tom firings with up to 8 segments. The controller can
store 4 Ramp-Hold programs in memory. Programs are
numbered 1 - 4.
Type of Firing Suggested Firing Mode
Enameling Single Segment
Silver Clay Single Segment
Glass Bead Annealing Ramp-Hold
Glass Fusing Ramp-Hold
Glass Slumping Ramp-Hold
Lost Wax Ramp-Hold
How to Select a Firing Mode
1. From IdLE display, press START/STOP once.
2. Press the Up Arrow key several times. You will see
the following display messages:
SPd1:
Single Segment 1 / 200°F/111°C rate per hour
SPd2:
Single Segment 2 / 500°F/277°C rate per hour
SPd3:
Single Segment 3 / 1000°F/555°C rate per hour
(List continues on next page.)
Single Segment Programming Instructions
Note: Single Segment firing is all you will ever need
if you are only going to a temperature and holding.
1. From IdLE, press START.
2. Use the Up Arrow key (not the Down Arrow)
to select a firing rate (temperature rise pre
hour) from 1 through 5.
SPd1 / (200°F or 111°C)
SPd2 / (500°F or 277°C)
SPd3 / (1000°F or 555°C)
SPd4 / (1500°F or 833°C)
SPd5 / (Full Power)
Then press START.
3. °F or °C and the target temperature from
the last firing will appear. Use the arrow keys
to change the target temperature. Then press
START.
4. HLd and the hold time from the last firing will
appear (e.g. 1 hour, 10 minutes = 01.10). Use
the arrow keys to change the hold time. Then
press START.
5. Strt will appear. Press START to begin firing.
-On- will appear, the Run indicator light will
begin blinking, and the kiln will begin firing.
To stop a firing before completion, press START/
STOP. StOP will appear, alternating with kiln tem-
perature and total firing time.
Note: Do not be concerned if your kiln makes a
clicking sound during firing. Kilns use relays to
power the elements. The relays click each time their
electrical contacts come together.
Note: The firing speed you select (see step 2) is a
pre-programmed speed. The kiln’s actual firing
speed may be less, depending on the kiln model,
available voltage, and density of the load you are
firing.
When the kiln fires to completion, the controller
will beep for 30 seconds. The display will show the
following:
 Firing time
 Present temperature
 CPLt = Fired to completion
To return to IdLE , press START.
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SPd4:
Single Segment 4 / 1500°F/833°C rate per hour
SPd5:
Single Segment 5 / Maximum rate
PrO1:
Ramp-Hold, Program 1
PrO2:
Ramp-Hold, Program 2
PrO3:
Ramp-Hold, Program 3
PrO4:
Ramp-Hold, Program 4
(To get back to IdLE , press START/STOP several times
until IdLE appears.)
Temperature Over-Shoot
When a kiln is heated too fast, it may over-shoot the
target temperature, especially in small kilns at lower
temperatures. To avoid this, add an extra segment in a
Ramp-Hold program to slow the firing. The segment
with the slower rate should begin approximately 40° -
60° below the target temperature.
Ramp-Hold Mode
You can make your own firing programs and store
them in the controller’s memory. A firing program tells
the kiln how fast to fire, and to what temperature. The
simplest program is one segment. You can use up to
eight segments with your controller in Ramp-Hold
mode.
Each segment includes a firing rate and firing tem-
perature. You can also soak, or hold, the temperature for
a specified period. Each segment stores three details:
 rate (temperature change in degrees per hour)
 target temperature
 hold at the target temperature (not always used)
The controller can retain four programs in memory
even when power is turned off. Programs are numbered
1 - 4.
The first message to appear after you plug in your
Sentry Xpress is IdLE. Press START. Then use the Up
Arrow key to scroll through these messages: PrO1 PrO2
PrO3 PrO4 SPd1 SPd2 SPd3 SPd4 SPd5.
To use Ramp-Hold mode for the rst time, select PrO1.
You do that pressing the START key after PrO1 appears.
Then follow the boxed instructions on page 7 to enter
temperature, heating rate, etc.
PrO1 is Program 1. When you re the kiln again, you
can repeat Program 1 by selecting PrO1. When you are
ready to re a dierent program, select PrO2, which is
Program 2. Then enter temperatures, heating rates, etc.
Select Program 3 and 4 the same way.
A program can have up to 8 segments, but you don’t
have to use all 8 segments. Use only the number needed
per ring. Often one segment is all you will need. Zero
out the unused segments. The instructions on page 7
explain how to do that.
You can over-write a program by selecting it and
entering new rates and temperatures. This automatically
over-writes the previous program. Write down your pro-
grams in a notebook and record ring results for all r-
ings.
Repeat Firings
To repeat the last firing, press ENTER from IdLE.
The kiln will begin firing. But first, make sure you are
repeating the correct firing by using Program
Review (page 3).
Programming a Cooling Segment
For controlled cooling, program a segment to a
lower target temperature than that of the preceding
segment.
Example: You fire at a rate of 500°F per hour to
1450°F with your first segment. You want the kiln to
cool at a rate of 100°F per hour down to 700°F. Here
is how you would program the two segments:
Segment
Rate
°F/°C
Temp.
°F/°C Hold
1 500/277 1450/788 00.00
2 100/55 700/371 00.00
The first segment is the heating segment. The second
one is the cooling segment. The controller does not use
minus numbers for cooling. Just enter a lower target
temperature than that of the previous segment.
If you prop the lid or door for a fast cooling, program
a fast cooling rate for that segment. If you lower the
temperature quickly by propping the lid but program a
slow cooling rate, the controller will just raise the tem-
perature again.
Example: Some glass artists flash-cool the glass just
after it fuses. They open the door a few inches to remove
heat, then close it again. This takes the glass down rap-
idly through the devitrification range. To program a
flash-cool, use maximum rate. This shuts off the heating
elements during that segment, allowing the kiln to cool
rapidly.
Note: During fast cooling, do not open the door all the
way. Do not force-cool the kiln with a fan.

A Ramp-Hold Practice Program
To practice using the controller, we will enter a pro-
gram that includes three segments. The last segment is
a cooling segment.
Using the programming instructions on the next col-
umn, enter this firing schedule. The use Program Review
(page 3) to check for accuracy.
PrO1
rA1 = 250
°F 1 = 750
HLd 1 = 00.00
rA2 = 900
°F 2 = 1425
HLd 2 = 00.30
rA3 = 150
°F 3 = 750
HLd 3 = 00.00
RA4 = 0000 (zeroes cancel segments 4-8)
Skipping a Segment in a Ramp-Hold Program
You can skip a segment in a Ramp-Hold program as
follows:
1. The kiln is firing. Press the Up Arrow key.
2. SStP will appear. Press the Up Arrow key again.
The firing will skip to the next segment.
Skip Segment Example
 Skipping to a Cooling Segment: You have pro-
grammed a target temperature of 1425°F for glass
fusing, followed by a segment for controlled cooling.
Watching the glass through the peephole, you notice
that the glass edges have rounded nicely at 1375°F.
Use Skip Segment to end the firing segment and
being one for slow cooling.
Note: Make a note of the temperature at which the
glass fused. Program that temperature for the next
firing of that type of glass.
Ramp-Hold Programming Instructions
Note: You have up to 8 segments available in
Ramp-Hold. If you don’t need all 8, zero out the
unused segments. See step 6 below.
1. From IdLE press START.
2. Press the Up Arrow key (not the Down Arrow).
PrO1 PrO2 PrO3 and PrO4 are Ramp-Hold
programs. When the one you want appears,
press START. (Ignore SPd1 - SPd5.)
3. rA 1 will appear. Enter  ring rate (tempera-
ture change per hour) for segment 1. (1° =
slowest rate. 1799°F/999°C = full power.) Then
press START.
4. °F 1 or °C 1 and the target temperature from
the last firing will appear. Use the arrow keys
to change the temperature. Then press START.
5. HLd 1 and the hold time from the last firing
will appear (e.g. 1 hour, 10 minutes = 01.10).
Use the arrow keys to change the hold time.
Then press START.
6. Continue entering values for the segments
needed. When rA_ appears for the next seg-
ment that you don’t need, select 0000. The
press ENTER. This will zero out the remaining
segments. (Example: You need only 1 seg-
ment. When rA 2 appears, enter 0000.
7. Strt will appear. Press START to begin firing.
-On- will appear, the Run indicator light will
begin blinking, and the kiln will begin firing.
To stop a firing before completion, press START/
STOP. StOP will appear, alternating with total firing
time and kiln temperature.
Note: Do not be concerned if your kiln makes a
clicking sound during firing. Kilns use relays to
power the elements. The relays click each time their
electrical contacts come together.
Note: The kiln’s actual firing rate may be less than
the rate you programmed, depending on the kiln
model, available voltage, and density of the load
you are firing.
When the kiln fires to completion, it will beep for 30
seconds. The display will show the following:
 Firing time
 Present temperature
 CPLt = Fired to completion
To return to IdLE , press START.
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Lost Wax Burnout
CAUTION: Only kilns with vent holes are designed for
lost wax burnout. However, you may be able to use a
kiln without the vent hole provided that you open the
door ½” during venting.
CAUTION: Always use a wax tray.
Note: These instructions apply to injection wax that
melts at 200°F, not pattern waxes and plastics that melt
at higher temperatures. If smoke appears during wax
elimination, turn off the kiln. Smoking wax means the
kiln fired hotter than 300°F/148°C.
Overview
Lost wax casting is the process of carving a shape in
wax and then casting that shape in metal. After the wax
has been carved, a mold is made of the wax shape. The
mold is a negative image of the wax. The wax is later
melted out of the mold through hollow channels called
sprues.
Lost wax burnout is the process of preparing a casting
mold for the melted metal that will be poured into it.
The steps in lost wax burnout.
1. Melt the wax from the mold.
2. Remove wax from the kiln before raising the tem-
perature higher than 300°F/148°C.
3. Harden the mold at high temperature.
4. Maintain the mold at the casting temperature rec-
ommended for the type of metal that will be
poured into the mold.
CAUTION: Prevent wax or carbon from contacting the
kiln’s walls and elements. Carbon build-up inside a kiln
ruins the interior. Carbon conducts electricity and
causes elements to short circuit. Damage to elements
from contact will foreign materials is not covered by
warranty.
A Sample Program
See instructions on page 7 to enter this program:
Segment
Rate
°F/°C
Temp.
°F/°C Hold
1 500/277 300/148 01.00
2 500/277 1350/732 01.00
3 450/250 800/426 02.00
Segment 1 heats the wax to 300°F/148°C and holds it
for one hour, allowing it to drip from the mold.
Segment 2 hardens the mold.
Segment 3 lowers the temperatures to 800°F/426°C,
the typical casting temperature for silver. (Most types of
gold cast at 900°F/482C)
Note: Casting temperature depends on the size of the
mold. The temperatures above are only a guide. See
your jewelry supply dealer for temperature recommen-
dations.
Burnout Instructions
1. Place a metal tray inside the kiln on three ½” posts.
Place the mold on a wire mesh screen on top of the
tray. The mold’s sprue hole should be down. The tray
will catch melting wax as it drips from the sprue
hole.
2. Keep the kiln’s vent hole(s), if any, open during wax
elimination. If the kiln has no vent hold, leave the
door open ½”. This allows fumes to escape the kiln.
Heat the kiln to 300°F/148°C and hold it at that tem-
perature for at least one hour.
CAUTION: Do NOT heat the wax above 300°F/148°C.
Hold at 300°F/148°C for at least one hour. During this
hour, the wax will melt from the mold and drip into the
tray. If the kiln gets hotter than 300°F/148°C, the wax
may smoke and deposit carbon inside your kiln, causing
expensive damage.
3. After one hour at 300°F/148°C, open the kiln.
Remove the mold and wax tray. Pour the wax from
the tray and leave the tray out of the kiln until your
next wax elimination. (Do not leave the tray in the
kiln!)
4. Heat the mold to the temperature recommended
by your jewelers’ supply house where you pur-
chased the mold material. This is usually around
1350°F/732°C.
5. Lower the temperature to the casting temperature
of the metal. Hold at that temperature until you are
ready to begin casting. Remove the mold with
tongs. Wear protective gloves and safety glasses.
Saving a Carbon-Damaged Kiln
If you follow the above directions, your kiln should be
safe from wax damage. In some cases, a small amount of
carbon may form on the walls over a period of time. This
is due to the burning of wax residue that was left in the
mold. For this reason we recommend that you periodi-
cally fire the kiln to 1500°F/815°C as follows:
1. Open the vent cover(s) or leave the door ajar ½”.
2. Fire the kiln empty to 1500°F/815°C at a rate of
300°F/166°C with a one hour hold (01.00).

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Error Messages
bAdP/Bad Programming
The kiln will not fire because the program just entered
has a rate of 0000 in segment 1. Program the firing
again.
EtH/Electronics Too Hot
The temperature of the electronic circuit board is
above 158°F/70°C. This could damage the controller, so
the firing has been stopped. To prevent this, keep the
firing room cooler. Use better ventilation.
FaIL/Thermocouple Failure
The thermocouple, or temperature sensor, failed dur-
ing firing. Causes:
 Defective thermocouple or disconnected/loose wires
 Defective controller
 Electrical noise
Thermocouple Paperclip Test
Check the thermocouple
wire connection. (See your
kiln instruction manual.) If
connections are tight, per-
form this test:
1. UNPLUG the kiln or dis-
connect the power.
Remove the controller. Remove the two thermo-
couple wires from the back of the controller.
2. Cut a thin paperclip in half. Insert a U-shaped paper-
clip piece, or other piece of thin wire, where you
removed the thermocouple wires.
3. Plug in the kiln. If the controller displays room tem-
perature, replace the thermocouple. If it shows FaIL,
replace the controller.
TCR/Thermocouple Reversed
Thermocouple lead wire are reversed.
FtL/Firing Too Long
This message appears when both of the following
conditions are met:
 The temperature rise or fall is less than 27°F/15°C per
hour.
 The ring is 4 hours longer than programmed.
See “Controller display turn on. No heat in kiln,” page 11.
PF 1/Power Failure
The power failed during firing and temperature
dropped more than 180°F/100°C by the time the power
cam back on.
PF 2/Power Failure
The power failed during firing and kiln temperature
was below 212°F/100°C when the power came back on.
tC/Thermocouple Failure
The thermocouple failed or was disconnected during
the IdLE display. See “FaIL” in the column at left.
Selecting °F or °C Display
The controller can display temperature in either °F or
°C. If your controller shows a small display dot in the
lower right corner of the display, the temperature
shown is °C. No dot means °F. To change temperature
display:
1. UNPLUG kiln or disconnect power.
2. Remove the four screws that hold the controller to
the front kiln. Carefully remove the controller from
the kiln. Leave the wire attached to the controller.
3. Look at the back of the controller. A plastic jumper
on the back of the board determines the type of
temperature display. When the jumper connects
two pin-type terminals, display reads °F. When the
jumper is removed, display reads °C. Remove or
insert the jumper as desired. (You can purchase the
jumper from a computer supply store if necessary.)
4. Install the controller being careful not to jar compo-
nents on the back of the controller against the kiln
case.

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Display Messages
Abrt The firing was stopped.
CPLt Fired to completion. If the kiln is already hot-
ter that the programmed target temperature when
you begin firing, CPLt will appear immediately after
you begin firing.
dELA (Page 3) Delay is a count-down timer that
start the firing when the time runs out.
°F or °C (and temperature) (Pages 5, 7) The target
temperature (the temperature that the kiln will fire
to). Each segment has a target temperature.
FULL Full power firing rate. At this setting the kiln
will fire at its fastest rate. There are two ways to
select full power:
1. Select SPd5 in Single Segment mode.
2. Select a rate of 1799°F/999°C at the ra _ prompt
in Ramp-Hold mode. A fast way to do this is to
press the Down Arrow key once from 0000.
FULL will appear.
HLd (Pages 4, 5, 7) Hold time of a segment, shown
in hours and minutes. (Example: 2 hours and 15
minutes = 02.15)
IdLE (Pages 3) The controller is ready for you to
enter a program or to begin a repeat firing.
-On- Firing has begun. A moment after -On-
appears, you will hear the relay(s) clicking.
PrO1 PrO2 PrO3 PrO4 (Pages 5, 6, 7) These are
Ramp-Hold programs stored in memory.
ProG (Page 4) These are Ramp-Hold programs
stored in memory.
rA 1 rA 2 etc. (Rate) (Page 7) This appears in Ramp-
Hold programming for each segment. 1, 2, etc. are
segment numbers. Enter the rate of temperature
change for that segment numbers. Enter the rate of
temperature change for that segment. Rate is fig-
ured in degrees of temperature change per hour.
Example:
A temperature rise of 100° in two hours = 50° rate.
A temperature drop of 200° in one hour = 200° rate.
SPd1 SPd2 SPd3 SPd4 SPd5 (Page 5) These are
Ramp-Hold programs stored in memory.
SStP (Skip Step) (Page 7) This message appears
when you press the Up Arrow key during a Ramp-
Hold firing. If you press the Up Arrow again, the fir-
ing will skip out of a segment into the next segment.
STOP The firing was stopped by pressing START/STOP.
Strt The “Ready to Start” message appears after
programming a firing. Press START to begin firing.
Trouble Shooter
Problem: Controller display is blank.
No heat in kiln.
 Is the kiln connected to the power?
 Has the circuit breaker tripped
or fuse blown?
 Is power reaching the wall
receptacle? Test with a volt-
meter or a test light if you are
not sure.
 Has the kiln switch box ½
amp fuse blown?
The kiln’s ½ amp fuse is locat-
ed in the kiln switch box. Remove by pressing the fuse
holder and turning counter-clockwise half a turn. Check
the fuse by placing the probes of an ohmmeter on the
ends of the fuse. If the ohmmeter reads less than an
ohm (digital meter) or reads 0 ohms (analog meter), the
fuse is okay. If the reading is OPEN (digital meter) or
infinity/no needle movement (analog meter), the fuse is
bad.
Replacement fuse: AGC ½ A 250V AC
 Is the controller receiving power? Test with a power
INPUT connections on the back of the controller with
a voltmeter.
Controller Power Input
Test
Unplug the kiln. Remove the
4 screw holding the controller
faceplate to the switch box. Lift
faceplate out of box and let the
board hang on the box with
the back of the board facing
you. Plug the kiln back in. Touch voltmeter probes (in AC
mode) to both INPUT connections (the white and orange
wires).
CAUTION: Do not let the back of the board touch a
grounded object. Make sure the voltmeter is in the AC
mode when placing the probes on INPUT connections.
Controller Power Input Test Result: No voltage
UNPLUG kiln. Check the switch box for disconnected
wires between the cord, transformer, and controller. If
wiring is okay, replace the transformer.
Controller Power Input Test Result: 20-24 volts AC
Correct current is reaching the board from the trans-
former. But since the board is not lighting up, it is probably
defective. Return the controller for repair or replacement.

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Controller Power Input Test Result: less than 20 volts
Did you recently replace the transformer? It may be
the wrong voltage. The voltage is below 20, which is not
enough power for the controller. To find out the cause of
low voltage, continue below:
Controller Input Test #2
The back of the board is still
facing you and the kiln is
plugged in. Remove the
INPUT plug, which is the
white, orange, and blue wires,
from the back of the control-
ler. Touch a voltmeter probe to the white wire and the
other probe to the orange wire.
Input Test #2 Result: Less than 20 Volts AC
There are two possible reason: 1) Low voltage at the
wall receptacle; 2) defective transformer. If wall recep-
tacle voltage is correct, replace the transformer.
Input Test #2 Result: 20 - 24 Volts AC
The transformer is sending correct voltage to the con-
troller. Yet when the INPUT plug was connected to the
controller, voltage was less than 20. This means the con-
troller is draining the voltage and is defective. Return
the controller for repair or replacement.
Problem: Controller display turns on.
No heat in kiln.
 Is the relay making its normal clicking sound?
Yes, the relay is clicking
Test the elements with an ohmmeter.
Element Resistance Test
1. UNPLUG kiln/disconnect the power. Open the
kiln’s switch box. Make sure the wires connect-
ing the relay to the elements are secure. If con-
nections are okay, continue to step 2:
2. Touch the ohmmeter leads to the two element
connectors of each element. A no-needle-
movement reading on an analog meter, or
OPEN on a digital meter, indicates a broken
element.
If the elements check out okay, replace the relay.
Note: To replace relay, see your kiln’s instruction and
service manual.
No, the relay is not clicking.
We know the controller is receiving voltage, because
the display lit. But the voltage from the transformer may
be too low to power the relays. Perform the “Controller
Power Input Test,” page 10. If your controller passes the
Input Test, perform the “Controller Power Output Test”:
Controller Power Output Test
Is the controller sending voltage to the relay? Test
OUTPUT with a voltmeter:
1. UNPLUG kiln/disconnect the power. Remove the 4
screws holding the controller faceplate to the switch
box. Lift faceplate out of box and let the controller
hang on the outside of the box with the back of the
board facing you. Then plug the kiln back in. Program
the controller to fire to 1000°F at FULL rate in Ramp-
Hold mode. Press START.
2. Put the voltmeter in DC mode. (It must be in DC
mode when testing OUTPUT voltage.) Touch probes
to the red wire and black wire connection. Measure
voltage when the relay clicks on.
Output Test Result: No voltage at red and black wires
The controller is not sending power to the relay.
Return the controller for repair or replacement.
Output Test Result:10-14 v. at red and black wires
The controller is sending correct power to the relay.
Unplug kiln/disconnect power. Remove the kiln switch
box. Look for disconnected wires between the control-
ler, relay and elements. Check the wiring diagram to be
are connected to the correct terminals. Be sure connec-
tions are tight. If the wiring is okay, replace the relay.
Note: To replace relay, see your kiln’s instruction and
service manual.
Problem: Kiln switch box ½ amp
fuse keep blowing.
 What size fuse are you using?
Correct fuse: AGC ½ A 250V AC
If the fuse is correct size, perform the following test:
Kiln Switch Box ½ Amp Fuse Test
1. UNPLUG kiln/disconnect the power. Remove the 4
screws holding the controller faceplate to the switch
box. Lift faceplate out of box and let the board hang
on the outside of the box with the back of the board
facing you. Disconnect
both wire plugs form
the back of the control-
ler. Then plug the kiln
back in. Apply power to
kiln. If the ½ amp fuse
blows, replace the
transformer. (If the fuse does not blow, the problem is
the board or relay. Go to step 2.)
2. Connect the INPUT plug (orange, blue, and white
wires) to the board again. Leave off the OUTPUT
wire plug (the one with the red and black wires).
Program the controller to fire at 1000°F at FULL rate
in Ramp-Hold mode. Press START. If the fuse blows,
replace or service the board. (If the fuse does not
blow, the problem is caused by a short in the coil of
the relay. Go to step 3.)
3. UNPLUG kiln/disconnect the power. Reconnect the
OUTPUT wire plug Reinstall the board in the switch
box. Replace the relay.

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Shorthand Instructions
These instructions may be confusing until you have read more detailed instructions on single Single Segment, page 5, or
Ramp-Hold, page 7. Read the safety guidelines, page 2. After pressing the keys in left column, the center message will appear.
Single Segment
Keys to Press Display
IdLE
SPd1 thru PrO4
(Not Down Arrow) Select rate SPd1 (Sample rate)
°F or °C
Enter temperature 1900 (Sample temperature)
HLd
Enter hold time 00.00 (or hold time)
Strt
-O n - The kiln is now  ring
Ramp-Hold
Keys to Press Display
IdLE
SPd1 thru Pro4
(Not Down Arrow) Pro1 Select Program #1, 2, 3, or 4
rA 1
Enter Segment 1 rate 500 (Sample rate)
°F 1 or °C 1
Enter temperature 1900 (Sample temperature)
HLd 1
Enter hold time 00.00 (or hold time)
First segment not needed: enter a rate of 0000.
Strt
-O n - The kiln is now  ring