Mitsubishi Electric Q81BD-J61BT11 User Manual page 119

5 PROCEDURE BEFORE STARTING THE DATA LINK
CAUTION
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 Be sure to shut off all phases of the external power supply used by the system
before installing or removing the board and wiring. Not doing so may cause
damage to the product.
 When turning on the power and operating the module after installation and wiring,
always attach the computer's main cover. Failure to do so may cause an electric
shock.
 Always ground the SLD terminal of the board and the personal computer to the
protective ground conductor. Not doing so can cause a malfunction.
 Prevent foreign matter such as swarf or wire chips from being attached onto the
board. Failure to do so may cause fires, failure or malfunction.
 Be sure to fix the wires or cables connected to the board by placing them in a duct
or clamping them. If not fixed, cables may be dangled and accidentally pulled,
causing damage to the board and cables and malfunction due to bad cable
contacts.
 Do not install the control lines together with the communication cables, or bring
them close to each other. Doing so may cause malfunctions due to noise.
 When removing the communication cable or power supply cables from the board,
do not pull the cable. First loosen the screws where the cable is connected to the
board and then remove the cable. Pulling the cable that is connected to the board
may cause damage to the board and cable or malfunction due to bad cable
contacts.
 Always make sure to power off the system in advance when removing the
terminating resistor to charge the system. If the terminating resistor is removed
and mounted while the system is energized, normal data transmission will not be
guaranteed.
(1) As a countermeasure to power surge due to lightening, connect a
surge absorber for lightening as shown below.
AC
E1
POINT
(1) Separate the ground of the surge absorber for lightening (E1) from that of the
personal computer (E2).
(2) Select a surge absorber for lightening whose power supply voltage does no
exceed the maximum allowable circuit voltage even at the time of maximum
power supply voltage elevation.
Personal
computer
E2
Surge absorber for lightening
MELSEC
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