Basler Electric BE1-87T - Manual (Page 67)

9171300990 Rev V BE1-87T Installation 4-25
CAUTION
Assigning 30° Phase Shift Compensation requires disassembly of the relay,
and must be done when the relay has been taken out of service. Access to the
30° Phase Shift jumpers requires the removal of the Analog #2 Board, shown
in Figure 4-27. To avoid personal injury or equipment damage, do NOT
proceed unless thoroughly familiar with the instructions in the sections on
Relay Operating Precautions and Relay Disassembly: Precautions.
The position of a set of movable jumpers on Analog Board #2 determines the state of the internal
compensation. To gain access to these jumpers, it is necessary to remove Analog Board #2. Refer to the
topic RELAY DISASSEMBLY for instructions on gaining access to the circuit board then adjust the
jumpers shown in Figure 4-27 as follows:
30° Phase Shift Compensation Adjustment Procedure
• In cases where no phase shift is wanted, all three jumpers ( φ A, φ B, and φ C) shown in Figure 4-
27 are in the WYE-WYE position. (Relays are shipped with all jumpers in this position.)
• If one of the inputs requires a shift in phase, the jumpers for all three phases are moved as
follows:
1. The ∆ 2 position develops A-B, B-C, C-A.
2. The ∆ 1 position develops A-C, B-A, C-B.
NOTE
The result of each of these vector differences has a magnitude of the square
root of three times each component.
The internal phase shift compensation is performed electronically as shown in the chart of Figure 4-27.
The internal compensation can apply to any power transformer with any combination of wye, delta, or
autotransformer winding connections.
A procedure to check the differential balance is described later in this section, Checking the Relay
Settings and System Inputs.