04-3598_ABB_PVA11_T_1-3kVA_EN_REV-B.doc
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Modifications reserved
4.2.2
Bypass mode
– Code 1
When the UPS is operating in "Bypass mode”, the efficiency of the system is higher. In the event of
mains failure the load will automatically be transferred from mains to inverter within 4 ms. The battery
charger remains active in the "Bypass-
Mode”. The "Bypass-Mode” is recommended only if the loads can
tolerate interruptions of 4ms (transfer time from Bypass Mode to Online Mode).
The LCD display of a UPS in bypass mode is shown in Figure 6. The information on the mains, battery,
UPS output and load will be displayed and the word “BYPASS” and the code “1” will indicate the working
mode of the UPS.
Figure 6
: LCD display for UPS in bypass mode
In bypass mode, the UPS acoustic alarm sounds once every 2 minutes in bypass mode.
Note that in
Bypass mode the UPS does not have the backup function. For this reason, if the mains fail, the
UPS will be shut down.
4.2.3
Online mode
– Code 2
The Online mode provides the highest degree of protection, especially in the event of a mains
disturbance or failure. This operating mode is always recommended if the critical loads (computer
systems) will not tolerate any interruption of the supply (not even the shortest). In the unlikely event of an
inverter fault or overload condition the UPS will transfer the load automatically and without interruption to
the static bypass-mains supply (transfer time = 0 msec).
The LCD display of a UPS in online mode is shown in Figure 7. The information on the mains, battery,
UPS output and load will be displayed and the word “LINE” and the code “2” will indicate the working
mode of the UPS.
Figure 7: LCD display for UPS in online mode
