34 OVEN SYSTEMS

High Limit Thermostat

The high limit thermostat is a 250 VAC, 3-pole, manual-reset thermostat with a trip point of 572ºF (300ºC). 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 31).

Magnetron Thermostats

The magnetron thermostats are “open-on rise.” They are designed to open at 212ºF (100ºC), 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 thermostats are self-resetting.

Reset Button

Power Supply

The power supply outputs 24 VDC at 40 watts to the control board and relays.

Relay - K1 Filament

The K1 relay is a 240 VAC, 30 amp, double-pole, double-throw, 24 VDC relay coil. It switches power to the magnetron filament transformers.

Figure 31: High-Limit Reset Button

Keypad

The keypad is a 7 x 10 matrix membrane switch. For details on key functions, see page 9.

Magnetron Cooling Fans

The magnetron cooling fans supply air to the magnetrons, and are actuated by the K7 relay. They operate 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)

Relay - K2 Anode

The K2 relay is a 240 VAC, 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 240 VAC, 30 amp, double-pole, double-throw, 24 VDC relay coil. It shorts L1 and L2 if the monitor switch opens before the primary or secondary switches.

Relay - K6 Voltage

The K6 relay is a 240 VAC, 30 amp, three-pole, double-throw, 24 VDC relay coil. Applicable in North America only, it switches between 208 and

240VAC on the high-voltage transformer and

filament transformer taps (depending on incoming voltage).

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Turbo Chef Technologies i5 High Limit Thermostat, Magnetron Thermostats, Power Supply, Relay K1 Filament, Keypad