Check that exposed parts are acceptably insulated from the supply circuit before returning the repaired instrument to the customer.
INSTRUMENT (Exposed part)
� Checking method
Measure the resistance value between the both poles of attachment cup (Power supply plug) and the exposed parts (Parts such as Knob, Cover, etc. where the customer is easy to touch.) and check that the resistance value is 500 kohms or more.
Insulation tester (DC 500V)
SAFETY PRECAUTIONS
The following precautions should be observed when servicing. 1. Since many parts in the unit have special safety-related characteristics, always use genuine Hitachi�s replacement parts. Especially critical parts in the power circuit block should not be replaced with other makers. Critical parts are marked with _ in the circuit diagram and printed wiring board. 2. Before returning a repaired unit to the customer, the service technician must thoroughly test the unit to ascertain that it is completely safe to operate without danger of electrical shock.
