Input Dark Test Function - Mitsubishi Electric NZ2GFSS2 32D S1 User Manual

Input dark test function

This function outputs test pulses to turn off the external input signals (X) that are on and diagnoses contacts including
external devices for failure. Failures including circuit fixing and short-circuit faults can be detected. The OFF time for test
pulses and the number of pulse outputs used in one diagnostic can be set depending on the usage environment.
The input dark test detects a short-circuit fault that occurs between Xn (n: even number) and Xn+1. The Xn is
an input terminal to be connected to T0, and the Xn+1 is an input terminal to be connected to T1. Note that a
short-circuit fault between Xn and Xn or between Xn+1 and Xn+1 cannot be detected. Thus, do not use the
input dark test for a system where a short-circuit fault may occur between Xn and Xn or between Xn+1 and
Xn+1.
Test pulse
T0 T1
Safety remote I/O module
To use the input dark test function, use the test pulse output terminals (T) and connect input devices.
To use the input dark test function, use the input terminals and test pulse output terminals (T) of the safety remote I/O
module in the following combinations. An incorrect combination is regarded as a disconnection, and an error (input dark test
error) occurs.
• NZ2GFSS2-32D-S1
Test pulse output terminal
T0
T1
T2
T3
• NZ2GFSS2-8D-S1, NZ2GFSS2-16DTE-S1
Test pulse output terminal
T0
T1
When the input dark test is not executed, input devices can be connected with a combination of input
terminals and COM+ terminals.
NC
Test pulse
NC
X0 X1
Input terminal
X0, X2, X4, X6, X8, XA, XC, XE
X1, X3, X5, X7, X9, XB, XD, XF
X10, X12, X14, X16, X18, X1A, X1C, X1E
X11, X13, X15, X17, X19, X1B, X1D, X1F
Input terminal
X0, X2, X4, X6
X1, X3, X5, X7
8 FUNCTIONS
8.3 Input Diagnostic Function
8
101