Honeywell RMA801 User Manual page 6

Symbol Definition
Earth Ground: Functional earth connection. NOTE: This
connection shall be bonded to Protective Earth at the source of
supply in accordance with national and local electrical code
requirements.
Chassis Ground: Identifies a connection to the chassis or frame of
the equipment shall be bonded to Protective Earth at the source of
supply in accordance with national and local electrical code
requirements.
v RMA803 Remote Indicator User's Guide Revision 2