Emerson 40-200KVA Mode D'Emploi

The rectifier input, bypass and output are easily accessible from the front of the unit for installation. 

All require lug type terminations. They are connected to busbars on the front side of the Liebert

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 NX

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and below the circuit breaker, as shown in Figure 3. These busbars are accessible when the front 

side panel is removed. Busbars to connect external batteries are accessible from the front of the UPS.

The safety ground busbar is located below the Maintenance Bypass circuit breaker or to the right of 

the UPS Output breaker for 160-200KVA models as shown in Figure 3. The safety ground cable must 

be connected to the ground busbar and bonded to each cabinet in the system.
All cabinets and cable conduit should be grounded in accordance with local regulations.

For safety, it is necessary to install circuit breakers in the input AC supply and external battery 

battery cabinets, external to the UPS system. Given that every installation has its own 

characteristics, this section provides guidelines for qualified installation engineers with knowledge of 

operating practices, regulatory standards and the equipment to be installed.

• Protection from excessive overcurrents and short circuits in power supply input

External overcurrent protection for the AC output circuit is to be provided. See 6.4 - UPS 

Electrical Characteristics and Table 9 for overload capacity.
When an external battery supply not made by Liebert is used, the customer must provide 

overcurrent protection for the battery circuit.

When wiring the UPS with dual inputs, the Rectifier input and the Bypass input must be 

protected separately. Size the breakers according to the input currents shown in Table 8.

Risk of electrical shock from ground fault. Can cause injury and death.
Failure to follow proper grounding procedures can result in electric shock hazard to personnel 

or the risk of fire, should a ground fault occur.