APC 9000 installation manual Installation with parallel frequency converters

Characteristics

The table below 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 415 V and full rated load with a power factor of 0.9. For voltages of 380 or 400 V, 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	number of	total UPS	Mains 2 or load	cable
inverter	parallel-connected	rated output	line current	cross-section (1)
output	inverters	in kVA	in Amps	in mm²
in kVA
800	2	1600	2310	Please consult us*
	3	2400	3465	Please consult us*
	4	3200	4620	Please consult us*
900	2	1800	2598	Please consult us*
	3	2700	3897	Please consult us*
	4	3600	5196	Please consult us*

(1) cable cross-sections are given for copper conductors of the U1000 R02V type (increase by 30 % for aluminium conductors). They are calculated according to permissible temperature rise and allow for line voltage drops over a maximum length of 100 m. For greater lengths, the cross-sections should be chosen to limit voltage drops to 3 %.

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

Installation with parallel frequency converters I

mains 1

inverter 1

mains 1

inverter 2

load

mains 1

inverter 3

Fig. 1

Installation with parallel UPSs with a centralised SSC

mains 2

mains 1

mains 1

inverter 1

inverter 2

static switch cubicle

load

mains 1

inverter 3

Fig. 2

34006451EN/AC - Page 8