Omron NX-SL3300 User Manual page 155

Safety Input Unit
Safety input
function
Safety input data
Self-diagnosis
Test Pulse Evaluation
A pulse is output at a specific
interval to detect failure of or
wiring errors in the externally
connected device. The test pulse
that is used depends on the
safety device.
Dual channel evaluation
When safety terminal inputs are
used as dual channels, the two
inputs are checked for
consistency.
Other Functions
Input filters
ON delays and OFF delays can be set to prevent malfunctions caused by noise or by chattering of
externally connected devices.
Test output terminal short detection
A function that detects ground faults of external wirings that are connected to the test output terminals
I/O power supply monitoring
This function monitors the voltage range of the I/O power supply to ensure the operation of the internal
circuits.
The following pages describe the details of the individual safety input functions.
Test Pulse Evaluation
A test pulse with a specific period is output on the 24-VDC power line from a test output terminal to
detect wiring errors and failure of the externally connected device. The following parameters are also
used.
• Test Pulse Diagnosis
• Test Source
• Test Pulse Mode
NX-series Safety Control Unit User's Manual (Z930)
Safety CPU Unit
Safety I/O
Safety program
communications execution
Without test pulse
Mechanical contacts
Single-beam safety sensors
Non-contact door switches
For safety mat/safety edge
Single channel
There is no redundancy.
Dual-channel equivalent input
Make sure that the two inputs have the same value.
Dual-channel complementary input
Make sure that the two inputs have different values.
For safety mat/safety edge
A two-input logic check is made for a safety mat.
ON delay
OFF delay
4 Safety Control Unit Operation
Safety Output Unit
Safety output
Safety I/O
function
communications
Safety output data
4
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