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Hot-plug components
8.4Hot-plug power supply units
The BX400 S1 system unit has 4 bays for
All bays for power supply units are fitted with flaps which close automatically. This ensures sufficient cooling of the system components when you replace a power supply unit or fan module during operation.
The PSU bays must be fitted according to their numbering. Unoccupied PSU bays must be fitted with fan modules to ensure that the system components are properly cooled, see
PSU 1 | PSU 2 | PSU 3 | PSU 4 |
Figure 42: Numbering of the power supply unit bays
In the minimum configuration, the BX400 S1 system unit contains one hot swap power supply unit (PSU1). This enables a fully populated BX400 S1 system unit to run in low power mode. Full power mode requires at least two PSUs in 200 V environments or three PSUs in 100 V environments.
To provide a redundant power supply, a third or fourth power supply unit can be installed (PSU3 and PSU4) in 200 V environments. In 100 V environments a fourth power supply unit (PSU4) is required to provide a redundant power supply. If one of the four power supply units fails, the other two/three units will ensure the system unit continues to operate normally. The defective power supply unit can be replaced while the system unit is still running (hot swap).
BX400 S1 | Operating Manual | 119 |