Pilz PSS SB TESTER D - Manual (Page 22)

Tests/Measurements
5-4 Operating Manual: PSS SB TESTER
Separate test: Resistance between CAN_H and CAN_L
Abbreviation for this separate test in the “Results” window:
R CAN_H/CAN_L
Measurement of the resistance between CAN_H and CAN_L. You can use
this measurement to detect whether the terminating resistors are present
and whether they are the correct size (120
Ω
each).
In the upper section of the detailed display of results from this separate
test, four pieces of information are displayed: the lower limit, the upper
limit, the measured value and the result.
As the parallel connection of two 120
Ω
ferrule resistors should have a
resistance value of 60
Ω
, a lower limit of 50
Ω
and an upper limit of 85
Ω
is
pre-assigned. If the value measured on the resistor lies between the upper
and lower limit, the resistor will be assessed as “OK”.
Example: lower limit value: 50
Ω
upper limit value: 85
Ω
measured value 119.3
Ω
result: not OK
If you scroll down in the detailed display you will be able to see whether
the circuit between CAN_H and CAN_L is open, i.e. whether or not there is
a terminating resistor.
Three pieces of information are displayed: the limit value, the measured
value and the result.
The limit value of 250 000
Ω
is pre-assigned. If the value measured on the
resistor is greater than or equal to the limit value, the circuit is assessed as
open.
Example: limit value 250 000
Ω
measured value 119.3
Ω
result: No open circuit