Electrolux EI30MH55GB Service Manual - Page 12

EI30MH55GSA EI30MH55GBA EI30MH55GWA DESCRIPTION AND FUNCTION OF COMPONENTS DOOR OPEN MECHANISM The door is opened by pushing the open button on the control panel, refer to the Figure D-1. When the open button is pushed, the open button pushes up the open lever, and then the open lever pushes up the latch head.The latch heads are moved upward and released from latch hook. Now the door will open. Latch heads monitor switch contacts. CAUTION: BEFORE REPLACING A BLOWN MONITOR FUSE TEST THE STOP SWITCH, PRIMARY INTERLOCK switch, SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH FOR PROPER OPERATION. (REFER TO CHAPTER "TEST PROCEDURE"). NOTE: MONITOR FUSE AND SWITCH ARE REPLACED AS AN ASSEMBLY Latch hook THERMAL CUT-OUT (HOOD ) Stop switch This thermal cut-out located on the right base plate. It Door Primary interlock switch is designed to automatically turn on the hood fan motor whenever the hot air rising from the conventional range below causes the temperature at the thermal cut-out to rise to 140oF (60oC) or higher, thus removing this hot air from Monitor switch around microwave oven. When the temperature around the thermal cut-out drops to 113oF (45oC) or lower, the thermal Secondary interlock switch cut-out shuts off the hood fan motor. Open lever THERMAL CUT-OUT (OVEN ) Figure D-1. Door Open Mechanism STOP, PRIMARY INTERLOCK AND SECONDARY INTERLOCK SWITCHES The secondary interlock switch is mounted in the lower position of the latch hook and the stop switch is mounted in the upper position of the latch hook. The primary interlock switch is also 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 interlock switches. 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 switch 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 switch 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 the stop switch contacts close, and then the primary interlock 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 switch and secondary interlock switch contacts fail to open, the monitor fuse blows simultaneously with closing of the This thermal cut-out is located on the top of the oven cavity. It is designed to prevent damage to the oven unit if the food in the oven catches fire due to overheating produced by improper setting of cooking time or failure of control unit. Under normal operation, the thermal cut-out remains closed. However, the thermal cut-out will open at 293oF (145oC) causing the oven to shut down. 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 two-speed, single-phase, double pole induction type, requiring a hood fan capacitor. It is located outside the upper rear part of the oven cavity, is to remove, from around the oven, hot air rising from the conventional electric or gas range over which it is installed. This air is then expelled either vertically or horizontally through the customer supplied duct system, or discharged back into the kitchen. STIRRER MOTOR The stirrer motors drive the stirrer fans to stir the microwave radiation from the waveguide. HOOD LAMP The hood lamps are mounted at the hood lamp angle. The hood lamps can be turned off and on by touching the Light Options pad. And also the brightness can be varied to high or low by touching the Light Options pad. 12