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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 102.)
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 102.) 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”.
6. CC-Link interface and MODBUS
®
RTU do not have the insulation between them.
