Chapter 1
Basic Pointers
In This Chapter you will learn to . . .
G
Choose between Cone-Fire and Ramp-Hold
G
Use the controller in freezing or hot weather
G
Understand the display window layout
G
Easily repeat the last firing
G
Make a quick visual check of your thermocouple
G
Avoid overfiring your kiln
Two Ways to Fire Your Controller
The Sentry fires in two modes:
I
Cone-Fire
, based on pyrometric cones (page 10).
Quickly program a ceramic firing by selecting a cone
number and firing speed.
I
Ramp-Hold
is for those who want to design their own
firing schedules. Program custom firing rates and target
temperatures (page 14).
Ceramic kilns come with both Cone-Fire and
Ramp-Hold. Heat treating, glass fusing, and enameling
kilns come with Ramp-Hold only.
1
From
[IDLE]
display, press 1. If
[CONE]
appears,
you have Cone-Fire mode. If the 1 key does not re-
spond, you have Ramp-Hold mode only.
2
Press
STOP
to bring the controller back to
[IDLE]
.
If you have Ramp-Hold only, skip pages 10 - 13.
Hot and Cold Weather; Storage Sheds
It is okay to store the Sentry at sub-zero temperatures.
But before operating, raise the room temperature to at
least 32°F / 0°C.
The Sentry will register sub-zero °F / °C temperatures.
However, 32°F / 0°C is the lowest recommended operating
temperature.
Pointer:
Raise the room temperature with a space
heater before firing the kiln. Place the space heater
within a couple of feet of the control panel and let it
run for an hour or so. Or even hang a shop light
near the kiln to raise the temperature above
freezing.
The circuit board is rated for 176°F / 80°C maximum op-
erating temperature. However, the maximum recom-
mended temperature is 158°F / 70°C, measured at the con-
troller inside the kiln switch box. To lower the temperature,
open windows and blow air across the kiln’s switch box with
a fan. Place several fans in the room during hot weather.
(See page 25 to check circuit board temperature.)
High humidity will not adversely affect the Sentry unless
water condenses on the circuit board. In this case, do not
fire the kiln until the moisture has evaporated from the
board.
Thunder Storms and Power Surges
Unplug the kiln when not in use, especially during thun-
der storms and in areas that have frequent power surges. If
the kiln is part way through a firing when a storm begins, it
may be okay to continue the firing. When the kiln shuts off,
disconnect the power.
CAUTION:
When firing the kiln during a storm,
do not leave the kiln unattended.
How to Read the Display
Center Dot: Time
A center dot appears when
time is displayed. The dot sepa-
rates hours from minutes (i.e. 1
hour, 30 minutes = 01.30). Dur-
ing temperature display, the dot
disappears.
Three-Light Display
The Sentry turns on the heat-
ing elements through relays.
Power output lights appear in the
right side of the display when the
Sentry sends a signal to turn on the relays. This lets you
know when the elements turn on.
I
Single-Zone Kiln
When the Sentry turns on the relays,
the lights will appear. The number of lights that appear
depend on the number of relays in your kiln.
I
Multiple-Zone Kiln
The top light indicates power to
the top section of the kiln, the middle light power to the
middle section, and the bottom light power to the bot-
Keep the kiln lid or door closed when the kiln is not in use.
5
Hot weather pointer
: Blow a gentle stream of air through the control
panel of the kiln to reduce the temperature of the controller circuit board.
Try to avoid firing your kiln during thunderstorms. Keep the kiln discon-
nected from the power when not in use. (Lake Grapevine, Texas. Photo by
Jared Davidson.)
