Parallel Units Wiring - Delta Modulon DPH series User Manual

Main AC Source
Bypass AC Source
Bypass AC Source
Loads
7 Follow Figure 5-16 to ground the UPS, external battery cabinet(s), Delta or non-
Delta external maintenance bypass cabinet and connected critical loads.

5.5.4 Parallel Units Wiring

1. Only authorized Delta engineers or service personnel can perform installation,
wiring, panel & cover removal, maintenance and operation. If you want to
execute any action mentioned above by yourself, the action must be under the
supervision of authorized Delta engineers or service personnel.
2. Up to eight UPS units can be paralleled for redundancy and capacity expansion.
Only UPSs with the same capacity, voltage and frequency can be paralleled.
Please only use the provided parallel cable to parallel the UPS units. Otherwise,
parallel functions will fail.
3. When UPSs are paralleled, the length of each unit's bypass input cables plus
output cables must be the same. This ensures that the parallel UPSs can equally
share the critical loads in bypass mode.
4. The UPS rating voltage is 220/ 380Vac, 230/ 400Vac or 240/ 415Vac.
5. The external battery cabinet's rating voltage is ±240Vdc.
6. Before wiring, please read 5.5 Wiring thoroughly.
Delta or non-Delta External
Maintenance Bypass Cabinet
Input Breaker
or Switch (Q1)
Bypass Breaker
or Switch (Q2)
Manual Bypass
Breaker or
Switch (Q3)
Output Breaker or
Switch (Q4)
(Figure 5-17: Single Unit Dual Input Wiring Diagram)
The UPS will not work normally if the main AC source's neutral (N)
is not firmly connected or not connected to the Delta or non-Delta External
Maintenance Bypass Cabinet's AC Input neutral (N) terminal.
5-21
5 Installation and Wiring
Rear of
the UPS
AC Input Terminals
(R/ S/ T/ N)
Bypass Input Terminals
(R/ S/ T/ N)
UPS Output Terminals
(R/ S/ T/ N)
Battery Input Terminals
(+/ -/ N)
External Battery Cabinet