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Installation 4. Wiring Diagram
Note for Input
Note
1
．
The voltage input terminals for 3-phase 3-wire are different from those for others.
2
．
If the polarity for VT and CT are wrong, the measurement cannot be executed correctly.
3
．
Do not connect wires to the NC terminals.
4
．
In the case of low voltage, there is no need for grounding of the secondary sides of VT
and CT.
5
．
Always earth the terminal to the protective earth conductor. Earth the terminal with less
than 100 ohm of earth resistance. Otherwise there will be a false operation.
Note for Output
Note
1
．
Do not bunch pulse outputs, alarm outputs and digital inputs/outputs signal cables with
the main circuit or power cables, or install them close to each other. Keep the distance
between the inputs/outputs signal cables and the main circuit or power cables and high
voltage lines shown below, when they run parallel to each other.
Conditions
Distance
Below 600V and less than 600A
power lines
30cm or more
Other power lines
60cm or more
2
．
Analog outputs signal cables should keep the distance from the other power cables and
input signal (VT, CT and auxiliary power) cables, and should not be bunched. And use the
shielded cables or twisted pair cables so that it is not affected the noise, serge, and
induction. Also, the wiring cables should be as short as possible.
3
．
MODBUS
®
RTU interface and analog outputs of ME-4210-SS96 do not have the insulation
between them.
Note for MODBUS
®
RTU
Note
1
．
Use the shielded twisted pair cable. (Recommended cables: Refer to page 82.)
2
．
To the units at both ends of the MODBUS
®
RTU link, the 120-ohm resistance has to be
attached. This instrument can perform a 120-ohm termination by short-circuiting the
terminal of T/R- and Ter.
3
．
The earthing has to be connected to earth by a thick wire of low impedance.
4
．
Keep the distance between MODBUS
®
RTU link to power lines.
5
．
Connect to earth the SLD terminal at one end.
Note for CC-Link
Note
1. As for CC-link cable, use the designated cable. (Refer to page 82.) Ver.1.10-compatible
CC-Link dedicated cables, CC-Link dedicated cables (Ver.1.00) and CC-Link dedicated
high-performance cables cannot be used together. If used together, correct data
transmission will not be guaranteed. Also attach the terminating resister which matches
the kind of the cable.
2. Connect the shielded wire of the CC-Link dedicated cable to “SLD” of each module, and
ground both ends of the shielded wire using grounding via “FG”. The SLD and FG are
connected within the module.
3. Because the CC-Link transmission line is a small signal circuit, it should be separated
from any strong-current circuit by 10cm
�
or more. However, if it is laid parallel for a long
distance, it must be laid at least 30cm away. The terminal must be grounded before using.
4. The CC-Link transmission line should use an exclusive line that meets the requirements
for total wiring length, distance between stations, and termination resistance values
according to the communication speed. If you do not use an exclusive line or observe the
wiring requirements, communication may fail. (Refer to the “CC-Link Cable Wiring Manual”
about the exclusive line and wiring requirements.)
5. Connect the supplied “terminal resister” to each module at both ends of the CC-Link
system. Connect the terminal resistors between “DA” and “DB”.
