Installation with parallel frequency converters

Characteristics (cont.)

The table opposite serves as an example for an installation comprising up to four frequency converters or four parallel UPSs with a centralised SSC.

◗for installations with redundant units, take into account only the units required to supply the load power (e.g. for an installation made up of 3 parallel-connected rectifier-inverter cubicles, one being redundant, only 2 rectifier-inverter cubicles are used to determine Mains 2 and load currents and cable cross-sections);

◗this table has been drawn up for rated phase-to-phase Mains 2 and load voltages of 415V and full rated load with a power factor of 0.8. For voltages of 380 or 400V, multiply the indicated currents by 1.09 and 1.04 respectively, then modify the cable cross-sections accordingly if necessary.

The cable cross-sections in this table are for the parts illustrated in bold on the following block diagrams (installation examples, figures 1 and 2).

Parameters for Mains 2 and load cables for an installation comprising frequency converters or parallel UPSs with a centralised SSC.

rated inverter	number of	total UPS	Mains 2 or load	cable cross-section (1)
output	parallel-connected	rated output	line current	in mm2
in kVA	inverters	in kVA	in Amps	Copper	Aluminium
250	2	500	722	2 x 185	2 x 300
	3	750	1082	3 x 300	4 x 240
	4	1000	1444	4 x 240	4 x 400
300	2	600	866	2 x 240	4 x 185
	3	900	1299	4 x 240	4 x 400
	4	1200	1732	Please consult us*
400	2	800	1298	4 x 185	4 x 300
	3	1200	1947	Please consult us*
	4	1600	2596	Please consult us*

450	2	900	1154	4 x 240	4 x 400
	3	1350	1731	Please consult us*
	4	1800	2308	Please consult us*

500	2	1000	1444	4 x 240	4 x 400
	3	1500	2164	Please consult us*
	4	2000	2888	Please consult us*
600	2	1200	1731	Please consult us*
	3	1800	2598	Please consult us*
	4	2400	3462	Please consult us*

(1) cable cross-sections are given for copper	maximum length of 100 m. For greater lengths,
conductors of the U1000 R02V type. They are	the cross-sections should be chosen to limit
calculated according to permissible temperature	voltage drops to 3%.
rise and allow for line voltage drops over a

NF C 15-100 authorizes a maximum of 4 cables per phase.