34001813EN/AE - Page 21
2. Installation
Parallel UPS with external bypass cabinet and separate Normal and Bypass AC network inputs (6 UPS in parallel for 4PN)The requirements for the different system earthing arrangements (SEA) are similar to those for single UPS
configurations. In the diagrams on page 18, simply replace the single UPS units between points A, B and C by the
following parallel configuration.
The UPS installation may be equipped with earth-leakage protection upstream on the condition that the protection
apply to:
- the normal and Bypass AC inputs
- all the parallel-connected UPSs.
The standard diagrams presented below may be adapted to your needs by qualified personnel.
Connection for the Bypass AC input and the output cables to the external bypass cabinet must use cables having the same
length and size to ensure correct balancing of the Bypass AC input currents.
Normal AC
15
Bypass AC
16 14
Normal AC
15
Bypass AC
16 14
Normal AC
15
Bypass AC
16 14
Normal AC
Bypass AC
16 14
Q4S
Q3BP
Q5N
15
A
B
B
B
B
C