inform PDSP 33010, Инструкция по установке и эксплуатации

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Operation mode depends on the priority, inverter, rectifier and bypass preferences made by the
user and mains, separate by-pass mains and battery voltages.
Priority and inverter, rectifier and bypass preferences can be set by using the COMMANDS and
extra commands (EXTCMNDS) menus.
If operation in any of these modes is impossible, output voltage will not be present. In this case,
loads will not be fed, and “VSECFLR” message is shown on the LCD instead of operation mode.
5.1. Bypass Operation
Devices without separate bypass mains input, absorb energy from the mains. In devices with
separate bypass mains input, energy is drawn from the separate bypass mains.
Loads are fed via static bypass line.
Output voltage has the same amplitude, frequency and waveform as the input voltage.
Current drawn by the loads are only limited by the thermal/magnetic switches over the energy flow
path.
Voltage, frequency and waveform of the bypass supply shall be in their tolerance limits, and bypass
shall be enabled for the UPS to operate in this mode.
When the upper provisions are met, the UPS works in bypass mode in the following conditions:

During the start-up

If the bypass priority is selected

If the inverter is disabled or blocked

In case of a prolonged overload
You can save energy by selecting the bypass priority. Efficiency in bypass mode is higher than the
efficiency in normal mode. If the bypass priority is selected, the UPS will operate in bypass mode
whenever the frequency/waveform/rms value of bypass mains voltage is in their tolerance limits. If
the bypass voltage goes beyond these limits, the UPS switches into normal operation.
Mains Limits for Bypass Operation
Frequency, rms value and total harmonic distortion of the bypass mains input voltage has to be
between acceptable limits for the UPS to operate in bypass mode.
Different rms voltage upper and lower limits are present for the return from another operation
mode to bypass mode. This provides hysteresis and ensures that the device does not change
operation mode very often when the bypass mains rms voltage is close to one of the limits.
Bypass mains limits are software parameters. They can be changed upon request.
Bypass Operation mode does not provide perfect stability in frequency/waveform/rms value
of the output voltage like in Online Operation. Thus, the use of this mode should be carefully
executed according to the level of protection required by the application.
Bypass Operation mode does not provide electronic short circuit protection as provides in
Online Operation. If a short circuit occurs on the output during this operation, the
thermal/magnetic protection will act and all loads will be deenergized.
Prolonged overloads in Bypass Operation may cause the thermal/magnetic protection act. In
this case, all loads will be deenergized.