DESCRIPTION AND FUNCTION OF COMPONENTS
DOOR OPEN MECHANISM
The door is opened by pulling the door handle, refer to the Figure
Latch
Hook
Latch
Heads
Door
Sensing
Switch
Monitor
Fuse
Door | Monitor |
| Switch |
Secondary
Interlock
Switch
Figure D-1. Door Open Mechanism
CAUTION: BEFORE REPLACING A BLOWN MONITOR FUSE TEST THE DOOR SENSING SWITCH, PRIMARY INTERLOCK RELAY (RY2), SEC- ONDARY INTERLOCK SWITCH AND MONI- TOR SWITCH FOR PROPER OPERATION. (REFER TO CHAPTER "TEST PROCEDURE").
NOTE: MONITOR FUSE AND SWITCH ARE REPLACED AS AN ASSEMBLY
TEMPERATURE FUSE (MG)
The temperature fuse located near the waveguide is designed to prevent damage to the magnetron if an over heated condition develops in the tube due to cooling fan failure, obstructed air guide, dirty or blocked air intake, etc. Under normal operation, the temperature fuse remains closed. However, the temperature fuse will open at 302˚F (150˚C) causing the oven to shut down.
THERMAL CUT-OUT (HOOD )
DOOR SENSING AND SECONDARY INTERLOCK SWITCHES
The secondary interlock switch is mounted in the lower position of the latch hook and the door sensing switch in the primary interlock system is mounted in the upper position of the latch hook. They are activated by the latch heads on the door. When the door is opened, the switches interrupt the circuit to all components. A cook cycle cannot take place until the door is firmly closed thereby activating both inter- lock switches. The primary interlock system consists of the door sensing switch and primary interlock relay located on the control circuit board.
MONITOR SWITCH
The monitor switch is activated (the contacts opened) by the latch head on the door while the door is closed. The switch is intended to render the oven inoperative by means of blowing the monitor fuse when the contacts of the primary interlock relay (RY2) and secondary interlock switch fail to open when the door is opened.
Functions:
1.When the door is opened, the monitor switch contact close (to the ON condition) due to their being normally closed. At this time the primary interlock relay (RY2) and secondary interlock switch are in the OFF condition (contacts open) due to their being normally open contact switches. And the contacts of relay (RY1) are in the ON condition (contacts close).
2.As the door goes to a closed position, the monitor switch contacts are first opened and then the door sensing switch and the secondary interlock switch contacts close. (On opening the door, each of these switches operate inversely.)
3.If the door is opened, and the primary interlock relay (RY2) and secondary interlock switch contacts fail to open, the monitor fuse blows simultaneously with closing of the monitor switch contacts.
This thermal
THERMAL CUT-OUT (CAVITY )
This thermal
Under normal operation, the thermal
TURNTABLE MOTOR
The turntable motor rotates the turntable located on the bottom of the oven cavity, so that the foods on the turntable cook evenly during cooking. Turntable will turn in either direction. The turntable motor can be turned off by touching TURNTABLE ON/OFF pad.
COOLING FAN MOTOR
The cooling fan motor drives a blade which draws external cool air. This cool air is directed through the air vanes surrounding the magnetron and cools the magnetron. This air is channelled through the oven cavity to remove steam and vapors given off from the heating foods. It is then exhausted through the exhausting air vents at the oven cavity.
HOOD FAN MOTOR
The hood fan motor is a
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