Standby; Normal Operation; Eboost Operation; On Bypass - GE On-line VH Series User Manual

4.4.1

Standby

The UPS output is off, but the batteries are charging, see 3.6.2 step 5
4.4.2

Normal operation

See 4.3.1.
4.4.3

eBoost operation

As long as the mains is suitable for the load, the UPS is able to operate in a "green", high efficiency operating mode: the UPS
supplies the load from bypass, while keeping ready for operation in double conversion. You can adjust the setting of the
eBoost function using the Configuration tool provided on CD.
The output voltage range is -10% ~ +5% of nominal, while the frequency range is +/-5% of nominal (the latter can be
configured to +/-1%). Both voltage and frequency have to be OK for 5 seconds before eBoost operation is accepted. To
protect the load from repetitive oscillations of an unstable grid, eBoost operation will be inhibited for 10 minutes if mains is
disturbed more than twice in 30 seconds.
4.4.4

On bypass

The UPS is equipped with an automatic bypass switch. This switch automatically transfers the load to the mains if the UPS is
unable to deliver the demanded output power due to overload or over temperature.
If all 4 load LEDs illuminate, bypass operation is caused by an overload. If only green load LEDs illuminate (the red load LED is
off), bypass operation is caused by over temperature. Take appropriate measures: reduce load and/or temperature.
The UPS will switch back to normal operation when the overload has been removed or the temperature has dropped below
alarm level.
If a power failure occurs during bypass operation, the UPS will switch to battery operation and eventually, when the
batteries are depleted, output power is lost.
The bypass function can be disabled - see 4.4.7 and 4.5 for further details.
Fail safe bypass operation: if the UPS becomes defective, the load may be switched to bypass (provided that the bypass
function was not disabled). As the status of the UPS is unknown in this situation the indications on the operating panel may
differ.
4.4.5

On battery

The UPS uses the energy stored in the batteries: see section 8 'Batteries - runtime'.
The runtime capacity LED bar will show the remaining runtime. The UPS will shut down:

after the batteries have been discharged (automatic restart), or

if keypad 'O' is pressed (restart via front panel required) or

if a 'UPS shutdown' command is given by the computer (automatic restart)
Automatic restart depends on the setting of the 'auto restart' function:
- if set 'on' the UPS will automatically restart when the mains returns
- if set 'off' a manual restart is required, as in 4.2.1.
As default the 'auto restart' function is 'enabled'. The setting can be changed using the UPS monitoring software. For
more information please refer to the manual that came with the software.
4.4.6

Battery low (end of runtime)

If during 'on battery' operation the 25% LED starts blinking, the batteries are nearly discharged: the remaining runtime is less
than 2 minutes (default setting, adjustable via the UPS monitoring software). Controlled shutdown of any computer
equipment is absolutely necessary at this point. If the UPS operates at 100% load, the shutdown procedure should be
completed within 2 minutes after the 'battery low' alarm started. If only part of the output capacity of the UPS is used this
period can be longer, with aged batteries this period can be shorter.
When the batteries are fully discharged, the UPS is no longer able to power the connected equipment.
4.4.7

Bypass out of limits

The mains voltage or mains frequency are outside bypass input tolerance but inside UPS input tolerance (see section 8).
Bypass operation is inhibited: if for whatever reason the UPS is not able to deliver the required output, output power is lost. If
the input frequency is often out of tolerance – during which bypass operation is inhibited and an alarm is generated – it may
be useful to disable the bypass function after which the unit operates as a UPS without automatic bypass switch. See 4.5.
Modifications reserved
GE_UPS_OPM_VHU_208_2K0_3K0_XUS_V010.docx
Critical Power
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Operating Manual VH2000-3000 208V UL