Electrical Connections And Wiring; Identification; System Block Diagram - GE LPS-O Instruction Manual

3 HARDWARE DESCRIPTION 3.1 CASE ASSEMBLY

3.1.2 ELECTRICAL CONNECTIONS AND WIRING

Electrical connections are made to the case through four terminal blocks (A, B, C, D) mounted on the rear
cover plate. Terminal blocks A, B and C contain 32 terminal points, each consisting of a #6 screw threaded into
a flat contact plate. Terminal D contains 14 terminal points, each consisting of a #6 screw threaded into a flat
contact plate.
The top and bottom printed circuit boards connect directly to terminal blocks A, B and C via edge connectors
along the rear of the boards. The magnetics module is wired directly to terminal block D.
The middle printed circuit board is connected to the top and bottom circuit boards via the Bus Card connected
on the front side of the circuit boards. The magnetics module is connected via a card edge connector to the
bottom circuit board (input board). The current block contacts are rated to handle current transformer (CT) sec-
ondary currents.
3

3.1.3 IDENTIFICATION

The LPS-O system model number label is located on the front cover.
The terminal blocks located on the rear cover plate are uniquely identified by a label that is found along the
side of each terminal block Each terminal is also identified.
Four connectors, PL1, PL2 (A & B), and PL3 are used for serial communication between the LPS-O and a PC
or modem. All three communications ports work independently.

3.1.4 SYSTEM BLOCK DIAGRAM

Figure 3–5 is the LPS-O system block diagram, illustrating the external connections and the interconnections
between the system modules.
GE Power Management LPS-O Line Protection System 3-
5