Emerson Liebert NX 50 and 60 Hz - Manual (Page 52)

Battery Installation
40
2.6 Battery Circuit Breaker Box
The box contains a battery isolating circuit breaker and the circuit breaker controller board as also
mounted in the battery cabinet.
A range of battery circuit breaker boxes is available for use in installations where the battery is not
installed in the battery cabinet, in which case the appropriate battery box is fitted as close as possible
to the battery and connected to the UPS equipment as illustrated in Figure 25.
The battery circuit breaker box, used with the circuit breaker controller board, is required to protect
the battery from deep discharging and overcurrents. It also provides electrical isolation between the
UPS and the battery, permitting technical service personnel to reduce the risks involved in mainte-
nance work to a minimum. Inside the box are connection bars for power cables arriving from the UPS
and from the battery.
The control signal cable is connected to the circuit breaker controller board through the terminal
board.
The cable shield must be earthed to prevent induced noise affecting the control operation, and a sepa-
rate safety earth must be connected between the UPS unit and circuit breaker box.
The configurations in Table 9 are available, depending on the UPS power rating.
The BCB box contains a battery isolating circuit breaker and a circuit breaker controller board and
offers the following features:
• Short-circuit and End Of Discharge protection—The circuit-breaker (or internal UPS battery con-
tactor when fitted) automatically opens when the EOD voltage is reached
• UPS Emergency Stop compatibility—The circuit-breaker (or internal UPS battery contactor when
fitted) opens when the emergency stop button is pressed on the UPS front panel.
NOTE
The control cables from the UPS unit to the controller board must be made using a 5-core
shielded cable located in a separate conduit to that containing the battery power cables.
Table 9 UPS-circuit breaker configurations
UPS
Dimensions
HxWxD, mm (in)
Weight
kg (lb) Circuit Breaker
30 to 40 kVA
558x378x180
(22x14.9x7)
21.5 (47.4)
125A 4p
60 to 80 kVA 200A 4p
100 to 120 kVA 25 (55) 400A 4p
140 to 160kVA 825x530x195
(32.4x21x7.7)
30 (66) 400A 4p
200kVA 32 (71) 500A 4p
Listed weights do not include packaging.
NOTE
30 to 40kVA UPS models fitted with internal battery and any UPS models fitted with a Battery
Start kit contain an internal UPS battery contactor for automatic connection and
disconnection of the batteries and the battery circuit breaker undervoltage coil is not used.
Refer to 2.5 - Battery Control for details