Chapter 6 Installation And Wiring; Wiring; Wiring Precautions - Mitsubishi Electric MELSEC iQ-R Series User Manual

6
INSTALLATION AND WIRING
This chapter describes the installation and wiring of the pulse input module.
6.1

Wiring

This section describes the procedure to connect a pulse generator to the pulse input module.

Wiring precautions

To configure a highly reliable system and to make full use of functions of the pulse input module, the external wiring must be
insusceptible to noise.
The following shows precautions for connecting the pulse generator.
Wiring
• Use different cables for the AC control circuit and the external input signal of the pulse input module so that the pulse input
module is not affected by surge or induction on the AC side.
• Do not place or tie the cables together with the main circuit line, high voltage line, or load cable from the device other than
the programmable controller. Leave sufficient space from the high voltage line or the circuit that involves high frequency
such as the load main circuit of the inverter. Failure to do so may cause the module to be affected by noise, surge, and
induction.
• Check the rated voltage and terminal layout before wiring to the pulse input module, and connect the cables correctly. Input
of voltage beyond the rating or incorrect wiring may cause fire or failure.
• Do not apply a voltage to the input terminal that is higher than that specified in "Input voltage selection" of "Module
parameter". Doing so may cause fire or failure of the module. For details on the module parameter, refer to MELSEC iQ-R
Channel Isolated Pulse Input Module User's Manual (Application).
Measures to reduce noise
The pulse input module may malfunction if a pulsing noise is input. Take the following measures to reduce noise.
• Use a shielded twisted pair cable.
• Do not place the shielded twisted pair cable in parallel with a noisy power cable or I/O cable. Leave a space of at least
150mm from those cables. Connect modules at the shortest distance possible.
• Ground the shield wire with a ground resistance of 100 ohms or less.
• Ground the FG terminal of the pulse input module and the power supply module.
6 INSTALLATION AND WIRING
6.1 Wiring
6
23