Keep the kiln lid or door closed when the kiln is not in use.
35
12
5
6
7
8
11
12
Transformer
Relay
Thermocouple
Fuse
A digital kiln or furnace uses only six basic parts to control heat.
Understanding how they work simplifies trouble-shooting.
Helps protect the controller from power surges.
1. Fuse:
Reduces the power to 24 volts AC, which
2. Transformer:
operates the controller.
Controls temperature and rate.
3. Digital controller:
Senses temperature. The tip protrudes
4. Thermocouple:
into the firing chamber.
Turns the heating elements on and off.
5. Relay:
Receives a signal from the controller.
6. Heating elements
Located in the switch
box. AGC ½ amp,
250 v. AC.
Two wires of dissimilar metal join together in the
thermocouple tip. When heated, the wires produce
a small voltage, which the controller interprets
as a temperature.
Power flows to the elements
when the relay turns on.
Reduces power to 24
volts AC, which operates
the controller.
Orange
Blue
White
Heating
Element
The relay is a switch,
which is triggered by
the controller. A 12 volt
signal from the controller
energizes an electro-
magnet inside the relay. This
closes the switch, sending
power to the elements.
Black
Red
1
2
5
6
7
8
11
12
Orange
Blue
White
From power supply
Fused
leg
120 Volt
1
2
5
6
7
8
11
12
Orange
Blue
White
From power supply
Fused
leg
208 &
240 Volt
Orange
Blue
White
From power supply
Fused
leg
120 Volt
1
2
5
6
7
8
11
12
Orange
Blue
White
From power supply
Fused
leg
120 Volt
Orange
Blue
White
From power supply
Fused
leg
208 &
240 Volt
New
Style
Old
Style
Using a transformer of the wrong voltage or connecting the
wrong wires to the transformer terminals can damage the
controller and cause the relays to chatter. Always make sure
your new transformer is the correct voltage before installing.
You can tell by looking at the jumper wires attached to the
terminals.
Red
Black
The red wire and black wire
contain extra push-on termi-
nals for kilns with three relays.
If your kiln has one or two
relays, cut off the extra
terminal(s) and wire(s). Spare
terminals or wires that touch
a grounded object could
damage your controller!
Wiring Single & Multiple Relays
Transformers
How to Wire the Sentry
Kilns with one thermo-
couple: use center terminals.
Observe color coding.
Kiln with 1 relay:
cut here
Kiln with 2 relays:
cut here
Sentry
Controller
Green
(grounding
wire)
RED
YEL
Top of Board
YEL
VIO
RED
BRN
BLK
GRN
BLU
WHT
ORG
USB
relays
power
thermocouples
P1
P7
P14
P13
P17
P9
P6 P11 P10
Factory ISP
Factory UART
Amp
Sensor
Lid
Switch
