CHAPTER 3: INSTALLATION
MDU Solutions
®
– UCrypt
®
IP to Analog 2
nd
Generation – Installation & Operation Manual
3-9
3.10 Equipment Safety Grounding
Reliable earthing of rack-mounted equipment should be maintained. Particular attention should be given to supply connections
other than direct connections to the branch circuit (e.g. use of power strips). The following guidelines are provided to clarify
the requirements for the installation to meet UL, CUL and CB standards. The use of the words “Ground” and “Earth” as well as
“Grounding” and “Earthing” may be used interchangeably and in this context, have the same meaning.
WARNING:
To comply with standards it is imperative that the chassis be connected to a
permanent building ground before connecting any power supply conductors due to high leakage
currents present in redundant power supply configurations. A warning label, shown in Figure 3-10,
is attached to all affected products.
The Device housing and power supplies must be connected to a permanent building ground in a manner that will ensure that
the exposed metal parts are constantly connected to ground through independent means even when the power supply cord
or wires may be disconnected temporarily. A ground connection screw terminal is provided on the rear panel to conveniently
effect such a connection.
3.10.1 Ground Connection
The supplementary equipment grounding conductor is to be installed between the rear panel ground screw and earth, that
is, in addition to the equipment ground conductor in the power supply cord or wires. The screw terminals provided for this
connection are located on the rear panel as illustrated in Figure 3-8 and Figure 3-9.
3.10.2 Ground Conductor Size
The supplementary equipment grounding conductor may not be smaller in size than the branch-circuit supply conductors
or a minimum #14 AWG. The supplementary equipment grounding conductor is to be connected at the rear panel terminal
provided, and connected to earth in a manner that will retain the earth connection when the power supply cord is unplugged.
The connection to earth of the supplementary grounding conductor shall be in compliance with the appropriate rules for
Rack Ground Buss
To building electrical ground system
Safety Ground Lug
Figure 3-8: 1RU Safety Ground Connection
Rack Ground Buss
To building electrical ground system
Safety Ground Lug
Figure 3-9: 2RU Safety Ground Connection
Figure 3-10: Leakage Current Warning Label
