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Rockwell Automation Publication 440R-UM014D-EN-P - December 2019
Chapter 2
Installation
Removal
To remove the MSR55P safety relay, use a screwdriver to pry the DIN rail latch
downwards until it is in the unlatched position. Then, swing the module up.
Spacing
MSR55P safety relays can be mounted directly next to other MSR and GSR
safety relays.
Maintain a space of 50.8 mm (2 in.) above, below, and in front of the relay for
adequate ventilation.
Removable Terminals
MSR55P safety relays have removable terminals to ease wiring and
replacement.
Figure 4 - Removable Terminals
1. Insert the tip of a small screwdriver into the slot near the terminal
screws.
2. To unlock the terminal block, rotate the screwdriver.
The terminal block can then be removed from the housing.
Spring Clamp Terminals
As an accessory, you can purchase removable terminals with spring clamps. The
spring clamp terminals can directly replace the screw clamp terminals. See
for the differences in wire size.
Enclosure Considerations
Most applications require installation in an industrial enclosure to reduce the
effects of electrical interference and environmental exposure. Pollution
Degree
2 is an environment where normally only non-conductive pollution
occurs except that occasionally temporary conductivity from condensation can
be expected. Overvoltage Category II is the load level section of the electrical
distribution system. At this level, transient voltages are controlled and do not
exceed the impulse voltage capability of the product insulation.
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