TurboChef i3 Service Manual

32 OVEN SYSTEMS
High Limit Thermostat
The high limit thermostat is a three-pole, manual-reset
thermostat with a trip point of 572
º
F (300
º
C). The
thermostat interrupts power to the main convection
heater in the event of an abnormal condition.
Reset the high-limit thermostat by pressing the reset
button (Figure 36).
Keypad
The keypad is a 7 x 10 matrix membrane switch. For
details on key functions, see page 9.
Magnetron Cooling Fan
The magnetron cooling fan supplies air to the
magnetrons, and is actuated by the K7 relay.
It operates at:
- 208/240 VAC (60 Hz installations with
voltage sensing)
- 220 VAC (60 Hz installations with no
voltage sensing)
- 230 VAC (50 Hz installations)
- 200 VAC (Japan installations)
Magnetron Thermostats
The magnetron thermostats are “open-on rise.” They are
designed to open at 212
º
F (100
º
C), which triggers an
F5 fault.
NOTE: The magnetron thermostats are wired in series.
If one opens, the control will switch off both microwave
systems until the open thermostat closes. The thermo-
stats are self-resetting.
Power Supply
The power supply outputs 24 VDC at 40 watts to the
control board.
Relay - K1 Filament
The K1 relay is a 240 VAC, 24 VDC coil, 20-amp,
sealed single-pole relay. It switches power to the
filament transformers.
Relay - K2 Anode
The K2 relay is a 30-amp, double-pole, double-throw,
24 VDC relay coil. It switches power to the magnetron
high-voltage transformers.
Relay - K3 Monitor
The K3 relay is a 30-amp, double-pole, double-throw,
24 VDC relay coil. It shorts L1 and L2 if the monitor
door switch opens before the primary or secondary door
switches.
Relay - K6 Voltage
The K6 relay is a 30-amp, three-pole, double-throw, 24
VDC relay coil. Utilized in North America only, it
switches between 208 and 240 VAC on the high-voltage
transformer and filament transformer taps (depending
on incoming voltage). Through the voltage sensor, the
oven defaults to the 240V position and switches to 208
if less than 222 volts is detected. 230V/400V interna-
tional ovens and all Japan models utilize the N.C.
contacts of this relay to power the magnetron circuit.
Figure 36: High-Limit Reset Button
Reset
Button

TurboChef i3 Specifications

General

Model	i3
Cooking Chamber	Stainless Steel
Cavity Dimensions	14.5 x 16 x 10 inches
Power Requirements	208-240V, 30A
Control Type	Touchscreen