Positron Teleline 751960/13CU5, Description And Installation Manual

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Teleline HVI Single 5-card Shelf Cabinet, model 751960/13CU5
3.9 Ground Wire
This cabinet must be connected to the substation grid ground. Provisions have
been made for connecting the cabinet to ground via the provided ground bar
located in the lower right hand area of the cabinet. See drawing 751960/13. The
lightning arrestor, 751112 shelf, and the secondary protector block are connected
to this same ground bar. The bar should be connected to the grid with a minimum
gauge #6 ground wire.
The length of the ground wire used to accomplish this task should be as short as
possible. The length should be 1.8 m (6 feet) or less external to the cabinet. After
the connection to the grid conductor is made, cut off all excess ground wire.
The connection to the grid conductor should be made with a clamp, sized for the
grid conductor and the cabinet grounding conductor. The use of a non oxidation
compounded is recommended. Exothermic welding of this connection would be
acceptable.
3.9.1 Grounding Connections For The NIU Shelf
The NIU shelf has two ground terminal positions that must be connected to
ground. The first is a Frame Ground and the second is a circuit ground. These
connections have been accomplished with the NIU on the following terminal
positions.
Table 12: NIU Terminal Positions
NIU Terminal Marked HVI Ground Bar
Ground Lug GND Symbol Outside the shelf, a ground
lug is installed Terminal #2
TB9 CKT GND Circuit Ground Terminal #3
3.9.2 Secondary Protector Modules
The station cable terminating block serves a dual purpose. One purpose is that of
a terminating block for the Teleline module output pairs and the station service
cable pairs. It is also a secondary protector block. The protector modules inserted
into the 5 pin receptacle are a balanced solid state PTC equipped module. These
modules must be plugged into the protector block field for the circuit to function