Mitsubishi Electric NZ2GN2S1-32D User Manual page 148

An input signal does not turn off No.2
■Cause
By using two power supplies, a sneak path is configured.
E1 E2
E1 > E2
■Action
• Use one power supply.
• To prevent the sneak path, connect a diode as shown below.
E1 E2
A signal incorrectly inputs data
■Cause
Noise is taken as input data.
■Action
• To prevent excessive noise, avoid installing power cables together with I/O cables.
• Set a longer input response time. ( Page 102 Input Response Time Setting Function)
• Connect surge absorbers to noise-generating devices such as relays and conductors using the same power supply or take
other noise reduction measures.
• To prevent noise from being taken in, take measures to reduce noise for the I/O cable by using a part such as a ferrite core.
• To prevent radiation noise, take measures to reduce noise by using a shielded cable.
11 TROUBLESHOOTING
146
11.5 Examples of Troubles with the I/O Module
DC input
Input
module
DC input
Input
module