IDEC FS1A Controller - Manual (Page 126)

5-85
Error detection function
Input monitoring
When an error is detected between the dual channel inputs, the SafetyOne changes to the
Protection state and displays "1" on the error LED display. The condition to be detected as an
input error is shown below.
(2) When there is an independent condition change of 1 of the inputs
The input LEDs blink and the monitoring output (Y
m
) outputs pulses (1 Hz), to notify the operator
of the corresponding input. See Fig. 5-4.
Note: The dependency of the 2 inputs is monitored with the dual channel dependent input
function, but the dependent time is infinite.
Short circuit and grounding detection
When an input error, such as a short circuit or circuit failure, is detected, the SafetyOne changes
to the Stop state and displays "2" on the error LED display.
Noise detection filter
When the SafetyOne is used in an environment with severe noise, the SafetyOne changes to the
Stop state and displays "9" on the error LED display.
Warning
Safety check signals (pulses signals) are supplied from the drive circuits (T
n
) to diagnose
connected safety devices and input circuits. Safety check signals can not be used as power for
connected devices.