54 | SAMLEX AMERICA INC.
APPENDIX A
i. First, the frequency of the Inverter Section is
NOT tracked at 0.1Hz per cycle as in Option “0= Fine”
[See Section 4.5.2.8(a) above]
but is made equal to the Generator frequency at zero crossing of the
Inverter voltage.
ii. Then, the phase of the Inverter voltage relative to the phase of the Generator voltage is tracked by 1º
per cycle. When the phase of the Inverter Section is within ± 10.5º of the Generator input voltage
waveform, the Transfer Relay is activated to transfer the AC load from the Generator to the Inverter
Section at zero crossing of the voltage waveform.
4.5.2.8.1 Programming Steps for Parameter "SYNC GRID"
Enter Key Up Key Enter Key Up Key x 7 times Enter Key
A N Y O P E R A T I N G
M O D E S C R E E N
ð
S E L E C T G R O U P
C H A R G E C U R V E
ð
S E L E C T G R O U P
I N P U T S E T T I N G
ð
D E F A U L T F R E Q
0 = 6 0 H z
ð
S Y N C G R I D
0 = F i n e
ð
K E Y I N P A S S WO R D
0 0 0 0
Password 8052
See Section 4.3.1
ð
S Y N C G R I D
0 = F i n e
4.5.2.9 SYNC GEN
(Table 4.4, Parameter Setup Screen No.9)
In EVO™, the frequency and phase of the Inverter Section are always kept synchronized with the AC input source
connected to terminals marked “GEN”
(7,8,9 in Fig 2.3)
. This facilitates faster and safer transfer of power between the
Inverter Section and the AC input source.
For supplementary details on synchronized transfer of AC power, please refer
to Sections 4.5.4 to 4.5.7 of the Owner’s Manual for EVO-2212/3012/2224/4024
.
Parameter “SYNC GEN” is used to program the desired
sensitivity
of frequency and phase synchronization of the Inverter
Section with the AC input voltage fed at the AC Input Terminals marked “GEN”
(7,8,9 in Fig 2.3)
. 2 programming
options are available for this parameter: (i) Option “1= Coarse” (Default option) – see Section 4.5.2.9(a) below and (ii)
“Option 0= Fine” – see Section 4.5.2.9(b) below
When EVO™ is operating in Inverting Mode
(there is no AC input)
, its output frequency will be equal to the frequency
that has been selected by the programming parameter “DEFAULT FREQ” i.e. 60Hz (Default) or 50Hz
(See TABLE 4.4
and Section 4.5.2.1)
. When AC input is made available at AC Input Terminals marked “GEN”
(7, 8, 9 in Fig 2.3)
, it is
first monitored for 2 sec. If it is within the programmed values of (i) frequency limits
(TABLE 4.4)
, (ii) low voltage limits
(TABLE 4.5)
and (iii) high voltage limits
(TABLE 4.6)
, synchronization process is initiated to synchronize the frequency and
phase of the Inverter Section with the incoming AC input voltage. Details are given below:
a) Parameter SYNC GEN set at Option 1= Coarse (Default)
This is the “
Default Setting
”. This setting is applicable when a Generator is connected to AC Input Terminals
marked “GEN”
(7,8,9 in Fig 2.3)
. As compared to very stable frequency of Grid /
Inverter Generator,
the
frequency of a Generator may vary considerably depending upon the performance of its Speed Governor that
compensates for the drop in RPM / frequency when electrical load is switched on / increased or, rise in RPM
/ frequency when electrical load is decreased / switched off. Hence, if synchronization sensitivity is set at “0=
Fine” as in Section 4.5.2.9 (b) below, it may take very long for the Inverter Section to synchronize with the
Generator or, may not synchronize at all. Under this option, the frequency and phase of the Inverter Section
are synchronized with the Generator
differently
as follows:
i. First, the frequency of the Inverter Section is
NOT tracked at 0.1Hz per cycle as in Option “0= Fine”
[See Section 4.5.2.9(b) below]
but is made equal to the Generator frequency at zero crossing of the
Inverter voltage.
SECTION 4 |
Parameter Setup