1 - 1
Safety Precaution for Repair
1
1-1 Cautions
Many electrical and mechanical parts have special safety-related characteristics. These are often not
evident from visual inspection nor can the protection afforded by them necessarily be obtained by using
replacement components rated for a higher voltage, wattage, etc. Replacement parts which have these
special safety characteristics are identified in this Service Manual. Electrical components having such
features are identified by marking with a on the schematics and the parts list in this Service Manual.
The use of a substitute replacement component which does not have the same safety characteristics as
the HITACHI recommended replacement one, shown in the parts list in this Service Manual, may create
shock, fire, or other hazards. Product safety is continuously under review and new instructions are issued
from time to time. For the latest information, always consult the current HITACHI Service Manual. A
subscription to, or additional copies for, HITACHI Service Manual may be obtained at a nominal charge
from HITACHI SALES CORPORATION.
PRODUCT SAFETY NOTICE
1-2 Electrostatic Protection Measures
Semiconductor components can be damaged by static electricity charged on clothes, human body,
etc. Take great care when handling components to avoid electrostatic damage, and perform
servicing in an environment where grounding is complete.
(1) Grounding work bench (Fig. 1-2-1)
Lay out an antistatic mat on work bench, and then use the ground plate to ground the work bench.
(2) Grounding human body (Fig. 1-2-2)
Use an antistatic wrist strap to discharge any static electricity charged on the body. Also, use a
tester for wrist strap to make sure that the wrist strap is working normally. Note, however, that
static electricity charged on clothes will not be discharged by wrist strap: Therefore do not allow
your clothes to touch the semiconductor components.
Fig. 1-2-1 Grounding Work Bench
Fig. 1-2-2 Grounding Human Body
Antistatic mat
Ground
1M ohm
Antistatic wrist strap
