Kohler PowerWAVE 6000 User Manual page 16

2: General Description
Load on bypass
In the load 'on bypass' mode the
UPS output supply is connected to
the unprocessed static bypass line
via the static switch.
This mode is invoked automatically
if there is an inverter problem, or
overload, which prevents the
inverter from producing its correct
output. It is also the normal mode of
operation when the UPS is used in
its 'ECO' mode.
Depending on circuit conditions,
when operating in this mode the
rectifier and charger sections can
be turned off entirely or remain
running and continue to provide battery charging. Similarly, the inverter can also remain operating on standby ready to be
brought back into use.
Inverter/Bypass load transfer
As illustrated in the above diagrams, the UPS output supply can be connected to the inverter by means of the output
contactor or to the static bypass line by means of the static switch. If both these devices are closed simultaneously it would
feed the bypass mains supply back into the inverter output and inevitably result in UPS damage. Therefore the operation
of the output contactor and static bypass is electronically controlled by the UPS load transfer mechanism such that their
closure is mutually exclusive and the load is transferred between them as quickly as possible to avoid any significant load
supply break.
Load on maintenance bypass
In this mode of operation the
manually closed maintenance
bypass switch (IA1) connects the
UPS output directly to the bypass
mains supply.
This mode is generally only used to
keep the load supplied (albeit
without any power protection) whilst
allowing the remainder of the UPS
to be shut down for service repair.
Note that when operating in the
maintenance bypass mode live
voltages are still present on the
UPS input and output power
terminals and power switches.
As with the static bypass line describe above, it is important that to avoid inverter damage the maintenance bypass and
inverter output are never connected in parallel. The UPS control system includes an interlock which prevents this from
occurring; however, when transferring from the 'load on inverter' to the 'load on maintenance bypass' mode it is important
that the load is first transferred to the static bypass ('load on bypass') before the maintenance bypass switch is closed.
CAUTION: Always follow the operating instructions in Chapter 5 of this manual when starting or shutting down
the UPS.
8
Maintenance Bypass Line
Bypass
Mains
Static Bypass Line
IA3
RECTIFIER
IA4
Input
Mains
Figure 2.5 Load on bypass
Maintenance Bypass Line
Bypass
Mains
Static Bypass Line
IA3
RECTIFIER
IA4
Input
Mains
Figure 2.6 Load on maintenance bypass
TS_610_01 PowerWAVE 6000 S3 (60-120kVA) User Manual 21/10/19
STATIC
SWITCH
INVERTER
Output
Contactor
CHARGER
BOOSTER
Batt. Fuse
STATIC
SWITCH
INVERTER
Output
Contactor
CHARGER
BOOSTER
Batt. Fuse
IA1
Output
Supply
IA2
Battery String
IA1
Output
Supply
IA2
Battery String