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Rockwell Automation Publication 440R-UM014D-EN-P - December 2019
Chapter 8
Troubleshooting
ERR Indicator Flashes 5 Times
(Step 5)
The MSR55P safety relay checks for simultaneity of the signals at L2 and L3. If
the signals are different for at least 2.5 s (one channel >V
m
and the other <V
m
),
a simultaneity failure is detected. The ERR semiconductor output turns on,
the ERR status indicator flashes failure code 5, and the OUT status indicator
turns off.
With power removed from the motor, measure the motor-winding resistance
as shown in
. If the resistance is different between L2 and L3, check
the wiring and measure the motor resistance at the motor.
If the motor resistance is the same on L2 and L3, then an internal fault exists
and the MSR55P safety relay must be replaced.
When the fault is corrected, the motor must be rotated above V
m
and then
stopped to reset the MSR55P safety relay. The fault reset does not depend on
the status of the X3/X2 connection; the reset occurs automatically.
Figure 23 - Simultaneous Error
ERR Flashes 6 or 7 Times
(Step 6)
Internally, the V
m
and t
s
adjustments rotate two potentiometers. When the two
potentiometers are not set to the same level, the ERR flashes and the ERR
semiconductor output turns ON.
To correct this situation, try to rotate the switch to a new position and then
back to the desired position. If the fault is not corrected, then replace the
MSR55P safety relay.
L1 L2 L3
Ohms
DMM
K4
K3
K2
K1
K2
K3
K4
A2
X1 X2
L3
L2
L1
X3
34 44
A1
A3
33
23
11
24
12
ON ERR A4
54
43 53
M
3~
Ch1=Ch2
First, remove power to
L1, L2, and L3
