22 | SAMLEX AMERICA INC.
SECTION 5 |
Description & Principles of Operation
5.6.5.2 Synchronized Type of Transfer in On Line Mode: Under this condition, Inverter is the Primary Source
and the AC GRID input is the Backup Source. Please refer to information in Table 5.2 below related to this
condition:
TABLE 5.2 SYNCHRONIZED TYPE OF TRANSFER IN ON-LINE MODE
Condition of AC GRID input
Operation when Inverter is
operating normally
Operation when Inverter fails and
auto resets subsequently
Frequency of AC GRID
input voltage is within the
“Synchronizable Frequency
Window” determined by
the parameter “SyncFREQ”
(see Section 5.6.4)
Inverter will be the Primary AC
Source and AC GRID input will be
the Backup AC Source.
The load will be powered by the
Inverter.
The frequency and phase of
Inverter voltage will be kept
synchronized with the frequency
and phase of the AC GRID input
voltage.
LED marked “AC GRID"
Green
LED marked “INVERTER”
Green
LED marked “BYPASS”
Off
LED marked “ALARM”
Off
Inverter failure
If the Inverter fails, the load will be transferred
to the AC GRID input in synchronized manner.
LED marked “AC GRID"
Green
LED marked “INVERTER”
Red
LED marked “BYPASS”
Green
LED marked “ALARM”
Orange
Inverter reset
If and when the Inverter resets
automatically, the frequency and phase
of its voltage will be slowly synchronized
with the frequency and phase of the AC
GRID input voltage. When synchronization
is completed, the load will be transferred
back to the Inverter at zero crossing of the
voltage waveform within < 8 ms
Frequency of AC GRID input
voltage is NOT within the
“Synchronizable Frequency
Window” determined by
the parameter “SyncFREQ”
(see Section 5.6.4)
Inverter will be the Primary AC
Source and AC GRID input will be
the Backup AC Source.
The load will be supplied by the
Inverter at a frequency that is
closest to the AC GRID frequency
as described below.
The frequency of Inverter voltage
will be adjusted to a value NOT
equal to but closer to value =
(“Output FREQ” + “Sync FREQ or
“Output FREQ” - “Sync FREQ”). For
example, if “Output FREQ” of the
Inverter = 60Hz, “Sync FREQ”=5
Hz and AC GRID input frequency =
50Hz, then the Inverter frequency
will be 55 Hz (60Hz – 5 Hz = 55Hz).
LED marked “AC GRID"
Orange
LED marked “INVERTER” Green
LED marked “BYPASS”
Off
LED marked “ALARM”
Off
Inverter Failure
If Inverter fails, transfer to the AC GRID
input will NOT be carried out because
the AC GRID input is NOT within the
“Synchronizable Frequency Window”.
The load will lose AC power
LED marked “AC GRID" Orange
LED marked “INVERTER” Red
LED marked “BYPASS” Off
LED marked “ALARM” Orange
Inverter Reset
If and when the Inverter resets
automatically, the frequency of Inverter
voltage will be adjusted to a value NOT
equal to but closer to value = (“Output
FREQ” + “Sync FREQ or “Output FREQ”
- “Sync FREQ”). For example, if “Output
FREQ” of the Inverter = 60Hz, “Sync
FREQ”=5 Hz and AC GRID input frequency
= 50Hz, then the Inverter frequency will be
55 Hz (60Hz – 5 Hz = 55Hz).
After the Inverter frequency is brought
closest to the AC GRID frequency as
described above, the load will be
transferred back to the Inverter.