Справочник Пользователя для Emerson UPS Systems

The Maintenance Bypass Cabinet requires both power and control cabling once it has been mechani-

cally installed. All control cables must be separate from the power cables. Run control cables in metal 

conduits or metal ducts that are electrically bonded to the cabinets they are connected to.
The cable design must comply with the voltages and currents provided in Tables 7 and 8, follow local 

wiring practices and take into consideration the environmental conditions (temperature and physical 

support media).
For cable entry terminal, refer to Figure 9.

The following are guidelines only and superseded by local regulations and codes of practice where 

applicable:

• Take special care when determining the size of the neutral cable (grounded conductor), because 

current circulating on the neutral cable may be greater than nominal current in the case of non-

linear loads. Refer to Tables 7 and  8.

• The grounding conductor should be sized according to the fault rating, cable lengths, type of pro-

tection, etc. The grounding cable connecting the UPS to the main ground system must follow the 

most direct route possible.

• Consider using smaller, paralleled cables for heavy currents as a way of easing installation.

Before cabling up the cabinet, ensure that you are aware of the location and operation of the 

external isolators that connect the input/bypass supply.
Check that these supplies are electrically isolated, and post any necessary warning signs to 

prevent their inadvertent operation.

Note: If a maintenance bypass 
cabinet is used, it must be 
installed on the right side of 
the Liebert NXL UPS