SHARP R-753(W)M
Manual de Servicio

SERVICING
WARNING TO SERVICE PERSONNEL
Microwave ovens contain circuitry capable of producing very high voltage and current. Contact with the following parts will result in electrocution. High voltage capacitor, High voltage transformer, Magnetron, High voltage rectifier assembly, High voltage harness. REMEMBER TO CHECK 3D 1) Disconnect the supply. 2) Door opened, and wedged open. 3) Discharge high voltage capacitor. WARNING AGAINST THE CHARGE OF THE HIGH-VOLTAGE CAPACITOR The high-voltage capacitor remains charged about 60 seconds after the oven has been switched off. Wait for 60 seconds and then short-circuit the connection of the high-voltage capacitor (that is, of the connecting lead of the high-voltage rectifier) against the chassis with the use of an insulated screwdriver. Sharp recommend that wherever possible fault-finding is carried out with the supply disconnected. It may in, some cases, be necessary to connect the supply after the outer case has been removed, in this event carry out 3D checks and then disconnect the leads to the primary of the power transformer. Ensure that these leads remain isolated from other components and the oven chassis. (Use insulation tape if necessary.) When the testing is completed carry out 3D checks and reconnect the leads to the primary of the power transformer. REMEMBER TO CHECK 4R 1) Reconnect all leads removed from components during testing. 2) Replace the outer case (cabinet). 3) Reconnect the supply. 4) Run the oven. Check all functions. Microwave ovens should not be run empty. To test for the presence of microwave energy within a cavity, place a cup of cold water on the oven turntable, close the door and set the power to HIGH and set the microwave timer for two (2) minutes. When the two minutes has elapsed (timer at zero) carefully check that the water is now hot. If the water remains cold carry out 3D checks and reexamine the connections to the component being tested.

When all service work is completed, and the oven is fully assembled, the microwave power output should be checked and a microwave leakage test carried out.

CAUTION/WARNING
CAUTION MICROWAVE RADIATION Service engineers should not be exposed to the microwave energy which may radiate from the magnetron or other microwave generating devices if it is improperly used or connected. All input and output microwave connections, waveguides, flanges and gaskets must be secured. Never operate the device without a microwave energy absorbing load attached. Never look into an open waveguide or antenna while the device is energized. Whilst the maximum leakage permitted in BS EN 60335-2-25 is 50Wm2 (equivalent to 5mW/cm2, it is not normal to detect any significant leakage, and therefore any detected leakage should be investigated. WARNING Servicing and repair work must be carried out only by trained service engineers. All the parts marked "*" on parts list are used at voltages more than 250V. Removal of the outer wrap gives access to potentials above 250V. All the parts marked "�" on parts list may cause undue microwave exposure, by themselves, or when they are damaged, loosened or removed.

WARNING
THIS APPLIANCE MUST BE EARTHED. THE WIRES IN THIS MAINS LEAD ARE COLOURED IN
ACCORDANCE WITH THE FOLLOWING CODE: GREEN-AND-YELLOW : EARTH BLUE : NEUTRAL BROWN : LIVE

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