S&C BankGuard PLUS, Руководство по установке

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8
S&C Instruction Sheet 1011-510
Ungrounded Wye Banks
Table 2. Potential device ratings.
Step 3
Using the terminal strip illustrations, make the following connections:
A. The station ground to TB2-1.
B. The output terminals of the potential device, with a system voltage rating as
shown in Table 2, to TB1-11 and TB1-12.
C. The opening circuit of the bank switch operator, to TB2-4 and TB2-5.
D. The closing circuit of the bank switch operator, to TB2-2 and TB2-3.
E. The control device power source (48 - 250 Vdc, or 88 - 280 Vac, 48 - 62 Hz), to
TB2-9 (for dc negative, ac neutral) and TB2-10 (for dc positive, ac hot).
F. The “b” contact of the auxiliary switch on the bank switch operator to TB2-6.
Terminal TB2-10 may be used as the source for the wetting voltage. Set this
contact to open near the fully-closed position of the capacitor bank switching
device.
G. The space heater source, where applicable (120 Vac/60 Hz or 240 Vac/60 Hz).
H. Alarm circuit (optional).
I. If unbalance compensation is required, connect the output terminal(s) of the
one (three) S&C 30-Volt-Ampere Potential Device(s) to TB1-9, TB1-10, DB2-11,
and TB2-12 (phase voltage return).
Step 4
If necessary, connect the potential devices or voltage transformers used for
unbalance compensation.
If the BankGuard Plus Control uses the optional unbalance compensation feature,
you must also connect the output terminals of other voltage monitoring devices:
A. To detect and compensate for the inherent capacitor bank imbalance only, in
applications where the source is grounded
, connect to one of the following:
• A single S&C 30-Volt-Ampere Potential Device rated for full system voltage,
connected to any phase of the station bus from which the capacitor bank
is tapped.
• A single voltage transformer, connected to the station bus from which the
capacitor bank is tapped—either phase-to-phase across any two phases, or
phase-to-ground on any phase.
B. To detect and compensate for the inherent capacitor bank imbalance only, in
applications here the source is a delta-connected tertiary transformer wind-
ing,
you must connect to a 1:1 voltage transformer, which is then connected to
Nominal Source
Voltage (kV)
Potential Device System
Voltage Rating (kV, Nominal)
below 23 23
23 23
34.5 23
46 23
69 34.5
115 69
138 69
161 138
230 138