Hitachi RAC-25WSE, Service Manual

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WORKING STANDARDS FOR PREVENTING BREAKAGE OF SEMICONDUCTORS
1. Scope
The standards provide for items to be generally observed in carrying and handling semiconductors in
relative manufactures during maintenance and handling thereof. (They apply the same to handling of
abnormal goods such as rejected goods being returned.)
2. Object parts
(1) Microcomputer
(2) Integrated circuits (I.C.)
(3) Field effective transistor (F.E.T.)
(4) P.C. boards or the like to which the parts mentioned in (1) and (2) of this paragraph are equipped.
3. Items to be observed in handling
(1) Use a conductive container for carrying and storing of parts. (Even rejected goods should be handled in
the same way.)
(2) When any part is handled uncovered (in counting, packing and the like), the handling person must
always use himself as a body earth. (Make yourself a body earth by passing one M ohm earth
resistance through a ring or bracelet.)
(3) Be careful not to touch the parts with your clothing when you hold a part even if a body earth is
being taken.
(4) Be sure to place a part on a metal plate with grounding.
(5) Be careful not to fail to turn off power when you repair the printed circuit board. At the same time,
try to repair the printed circuit board on a grounded metal plate.
HIT
ACH
I IC40
1TH
1 ,188
UV
Fig. 1 Conductive container
A conductive polyvinyl bag
IC
IC
Conductive sponge
Fig. 2 Body earth
Body earth (Elimik conductive band)
Clip for connection with
a grounding wire
1M
Ω
3