Specifications

3–5 System Installation Recommendations
Publication 1747-6.2
Special Grounding Considerations for DC Applications using
1746-P3
!
ATTENTION: Any voltage applied to the 1746-P3
DC NEUT terminal will be present at the SLC logic
ground and the processor DH-485 port. To prevent
unwanted potentials across the logic ground of the
controller and/or damage to the SLC chassis, the DC
NEUTRAL of the external DC power source must be
either isolated from the SLC chassis ground, or
connected to earth ground. See the figure below:
SLC 500 Chassis
1746-P3
Door
Processor
External DC Power Source
+24 VDC
DC Neut
+24 VDC
DC Neut
Chassis
Ground
Not Used
Not Used
DH-485
Port
SLC Logic Ground
Earth Ground
A jumper wire is recommended between
the DC NEUT and Chassis Ground of the
external power source.
•
Chassis
Ground
Earth Ground