Pilz PSS Series Operating Manual page 44

Fault Diagnostics
Signal test
Problem
Device's signal level lies
outside the measurable
range
Error message "Problem
CAN_L" is displayed
Error message
"Measurement not OK" is
displayed
Device's transmission
rate is incorrect
Real-time mode
Problem
Failure rate (fr/s) > 0
7-2
Cause
Connection is faulty or device
is defective
Short circuit between CAN_L
and earth
Connection between PSS SB
TESTER and SafetyBUS p is
interrupted or SafetyBUS p is
inactive
Device is defective
Cause
The transmission rate set on
the PSS SB TESTER may not
match the actual transmission
rate on SafetyBUS p
Correcting the problem
Check the connection. If
nothing helps, change the
device
Check line from CAN_L
Check whether SafetyBUS p
is active (SafetyBUS p status
LED on the PSS and devices
must be lit), check the
connection
Change the device
Correcting the problem
Check the transmission rate
setting
Operating Manual: PSS SB TESTER