Recommended Cable Sizes for IEC
DANGER 

hazard of electric shock, explosion, or arc flash
Failure to follow these instructions will result in death or serious injury.

The maximum number of cable connections per busbar:

4 on input/output/bypass busbars

4 x 240 mm^{2} on input/output/bypass busbars

4 x 240 mm^{2} or 8 x 150 mm^{2} on DC+/DC busbars

8 on N busbar

16 on PE busbar
Cable sizes in this manual are based on the minimum requirements in table B.52.3 and table B.52.5 of IEC 60364552 with the following assertions*:

90 °C conductors

An ambient temperature of 30 °C

Use of copper or aluminum conductors

Installation method F

Single layer on a perforated cable tray
PE cable size is based on table 54.2 of IEC 60364454.
If the ambient temperature is greater than 30 °C, larger conductors are to be selected in accordance with the correction factors of the IEC.
Copper
Copper
UPS rating  400 kW  450 kW  500 kW  

Voltage (V)  380  400  415  440  380  400  415  440  380  400  415  440 
Input phases (mm^{2})  2 x 150  2 x 150  2 x 150  2 x 150  2 x 240  2 x 240  2 x 185  2 x 150  2 x 240  2 x 240  2 x 240  2 x 240 
Input PE (mm^{2})  1 x 150  1 x 150  1 x 150  1 x 150  1 x 240  1 x 240  1 x 185  1 x 150  1 x 240  1 x 240  1 x 240  1 x 240 
Bypass/output phases (mm^{2})  2 x 120  1 x 240  1 x 240  1 x 240  2 x 150  2 x 150  2 x 120  1 x 240  2 x 185  2 x 150  2 x 150  2 x 150 
Bypass PE/output PE (mm^{2})  1 x 120  1 x 120  1 x 120  1 x 120  1 x 150  1 x 150  1 x 120  1 x 120  1 x 185  1 x 150  1 x 150  1 x 150 
Neutral (mm^{2})  2 x 120  1 x 240  1 x 240  1 x 240  2 x 150  2 x 150  2 x 120  1 x 240  2 x 185  2 x 150  2 x 150  2 x 150 
DC+/DC (mm^{2})  2 x 240  3 x 150  3 x 185  
DC PE (mm^{2})  1 x 240  2 x 120  2 x 150  
Inverter midpoint cable for 3wire parallel (mm^{2})  2 x 150  2 x 150  2 x 150  2 x 150  2 x 240  2 x 240  2 x 185  2 x 150  2 x 240  2 x 240  2 x 240  2 x 240 
Aluminum
UPS rating  200 kW  250 kW  300 kW  350 kW  

Voltage (V)  380  400  415  440  380  400  415  440  380  400  415  440  380  400  415  440 
Input phases (mm^{2})  1 x 185  1 x 185  1 x 185  1 x 185  2 x 120  2 x 120  1 x 240  1 x 240  2 x 150  2 x 150  2 x 150  2 x 120  2 x 185  2 x 185  2 x 185  2 x 150 
Input PE (mm^{2})  1 x 95  1 x 95  1 x 95  1 x 95  1 x 120  1 x 120  1 x 120  1 x 120  1 x 150  1 x 150  1 x 150  1 x 120  1 x 185  1 x 185  1 x 185  1 x 150 
Bypass/output phases (mm^{2})  1 x 150  1 x 150  1 x 150  1 x 120  1 x 185  1 x 185  1 x 185  1 x 185  2 x 120  1 x 240  1 x 240  1 x 240  2 x 150  2 x 150  2 x 120  2 x 120 
Bypass PE/output PE (mm^{2})  1 x 95  1 x 95  1 x 95  1 x 70  1 x 95  1 x 95  1 x 95  1 x 95  1 x 120  1 x 120  1 x 120  1 x 120  1 x 150  1 x 150  1 x 120  1 x 120 
Neutral (mm^{2})  1 x 150  1 x 150  1 x 150  1 x 120  1 x 185  1 x 185  1 x 185  1 x 185  2 x 120  1 x 240  1 x 240  1 x 240  2 x 150  2 x 150  2 x 120  2 x 120 
DC+/DC (mm^{2})  2 x 120  2 x 150  2 x 240  3 x 150  
DC PE (mm^{2})  1 x 120  1 x 150  1 x 240  2 x 120  
Inverter midpoint cable for 3wire parallel (mm^{2})  1 x 185  1 x 185  1 x 185  1 x 185  2 x 120  2 x 120  1 x 240  1 x 240  2 x 150  2 x 150  2 x 150  2 x 120  2 x 185  2 x 185  2 x 185  2 x 150 
Aluminum
UPS rating  400 kW  450 kW  500 kW  

Voltage (V)  380  400  415  440  380  400  415  440  380  400  415  440 
Input phases (mm^{2})  2 x 240  2 x 240  2 x 240  2 x 240  (3 x 185)*  (3 x 185)*  2 x 240  2 x 240  (3 x 185)*  (3 x 185)*  (3 x 185)*  (3 x 185)* 
Input PE (mm^{2})  1 x 240  1 x 240  1 x 240  1 x 240  2 x 150  2 x 150  1 x 240  1 x 240  2 x 150  2 x 150  2 x 150  2 x 150 
Bypass/output phases (mm^{2})  2 x 185  2 x 150  2 x 150  2 x 150  2 x 240  2 x 240  2 x 185  2 x 150  2 x 240  2 x 240  2 x 240  2 x 240 
Bypass PE/output PE (mm^{2})  1 x 185  1 x 150  1 x 150  1 x 150  1 x 240  1 x 240  1 x 185  1 x 150  1 x 240  1 x 240  1 x 240  1 x 240 
Neutral (mm^{2})  2 x 185  2 x 150  2 x 150  2 x 150  2 x 240  2 x 240  2 x 185  2 x 150  2 x 240  2 x 240  2 x 240  2 x 240 
DC+/DC (mm^{2})  3 x 185  3 x 240  4 x 185  
DC PE (mm^{2})  2 x 150  2 x 185  2 x 185  
Inverter midpoint cable for 3wire parallel (mm^{2})  2 x 240  2 x 240  2 x 240  2 x 240  3 x 185  3 x 185  2 x 240  2 x 240  3 x 185  3 x 185  3 x 185  3 x 185 
Guidance for Organizing Input, Bypass, And Output Cables
The input, bypass, and output cables must be grouped in circuits. On raceways, use one of the two shown cable formations.
Load Sharing in Bypass Operation in a Parallel System
The impedance of the bypass paths need to be controlled in a parallel UPS system. When operating in bypass mode, the parallel load sharing is determined by the total impedance of the bypass path comprising cables, switchgear, static bypass switch, and cable formation.
NOTICE 

Risk of equipment damage
To ensure correct load sharing in bypass operation in a parallel system, the following
recommendations apply:
Failure to follow these instructions can result in equipment damage.

ECOnversion Limits for Parallel UPS Systems
ECOnversion requires a minimum load percentage on the UPS for parallel UPS systems. The minimum required load percentages depend on the power cable sizes.
Standard ECOnversion Limits Based on Recommended Cable Sizes
UPS rating  Minimum load % 

200 kW  34% 
250 kW  27% 
300 kW  23% 
350 kW  19% 
400 kW  17% 
450 kW  15% 
500 kW  14% 
The other prerequisites to use this table include:

The values are calculated based on the use of recommended cable sizes.

Installations with maximum two cables on each phase are supported.

The bypass and output cables must have equal length for all UPSs.
Standard ECOnversion Limits Based on Nonrecommended Cable Sizes
UPS rating  Minimum load % 

200 kW  50% 
250 kW  40% 
300 kW  34% 
350 kW  29% 
400 kW  25% 
450 kW  22% 
500 kW  20% 
The other prerequisites to use this table include:

The values are calculated based on the scenario of using nonrecommended cable sizes.

Installations with three or four cables on each phase are supported.

The bypass and output cables must have equal length for all UPSs.
For 3Wire Parallel Systems Only
In a parallel installation installed as a 3wire AC configuration, the inverter midpoint of each UPS must be interconnected by cable in a daisy chain configuration. The inverter midpoint cable size can be found in the recommended cable sizes table.
When the inverter midpoint of the parallel UPSs is permanently connected, there is still potentially dangerous voltage present on the neutral busbar inside the UPS even after the UPS has been isolated from the parallel system for maintenance and has been completely shut down. Due to the dangerous voltages on the neutral busbar, all service activities that need access inside the I/O section by opening the inner door require full shutdown of the entire parallel system and transfer to maintenance bypass.
DANGER 

Hazard of electric shock, explosion, or arc flash
Failure to follow these instructions will result in death or serious injury.
