Page 295 - Electronic Mechanic - TP - Volume - 2

ELECTRONICS MECHANIC - CITS

DC voltage and/or current output of the rectifier. Periodic inspections should be made to assure desired
operation and prevent any overloading. Voltage adjustments should be made as required. A permanent record
of the current and voltage readings should be maintained. Any pronounced change that is not attributable to
current adjustment should be investigated.
8 Trouble shooting hints
A wiring diagram for use by experienced personnel is provided. Only experienced electrical personnel should
attempt location and repair of electrical difficulties, should they occur. Some symptoms of elementary trouble
and the possible remedy are as follows:

• No dc current or dc voltage output on just one zone. Check: fuse on auto board
• No dc current or dc voltage output on any zone.
• Check: ac overload protection for blown fuses (located behind main panel) or tripped circuit breaker. Check
ac power supply.

• Dc voltage but no dc current reading.
• Check: dc ammeter. Check dc connections and external dc circuit for electrical continuity.
• Dc current reading but no dc voltage reading. Check: check dc voltmeter
• Maximum rated dc voltage cannot be attained.

• Check: check ac line voltage. Check current adjustment settings for maximum. Check accuracy of dc
voltmeter.
• Maximum rated dc current cannot be obtained at maximum dc voltage.

• Check: check load resistance of external dc circuit. Check accuracy of dc ammeter.
• Check voltage across each thyristor , if faulty change the respective thyristor,
Result: Thus the demonstration on replacement of faulty components in the of faulty rectifiers have been done
successfully.

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CITS : E & H - Electronics Mechanic - Exercise 202&203