Samlexpower Evolution EVO-2212 Owner's Manual - page 64
64 | SAMLEX AMERICA INC.
K2
DPDT Transfer Relay (70A) for Grid, Line
•
Two 35A each poles are paralleled for 70A capacity
K3
DPDT Transfer Relay (70A) for Generator, Line
•
Two 35A each poles are paralleled for 70A capacity
K4
DPDT Transfer Relay (70A) for Neutral to Ground Bond Switching
•
Two 35A each poles are paralleled for 70A capacity
7,1 and 9,3
Normally Closed Contacts
7,4 and 9,6
Normally Open Contacts
QD
Quick Disconnect (13, Fig 3.9) for disconnecting Output Neutral to Chassis Ground
bond in Inverting Mode (Default - connected)
NOTE:
Relays are de-energized in Invertering Mode and are energized in Charging Mode
Fig 4.1(b) Operation of Transfer Relay and Neutral to Ground Bond Switching in EVO-3015 and EVO-4024
4.5.4 Synchronized Transfer of Power
Direct AC input from Grid and Generator can be fed simultaneously to separate AC Input
Circuits. Only one AC source is selected at one time. When both Grid and Generator are
available simultaneously, Grid has priority. To facilitate synchronization, transfer of power
from Grid to Generator or from Generator to Grid is always routed through the inverter.
4.5.5 Transfer From Inverter to Grid / Generator
When Grid / Generator becomes available, its voltage and frequency are checked if these are
within the programmed limits. If yes, the output voltage of the Inverter Section is synchro-
nized with Grid / Generator through Phase Locked Loop” (PLL). This synchronization process
takes few seconds. Once synchronization is completed, the load is transferred instantly (with-
in 1 ms) to Grid / Generator at Zero Crossing of the voltage waveform for seamless transfer
and for better protection of Transfer Relay contacts. The unit now operates in “Charging
SECTION 4 |
General Description & Principles of Operations
NEUTRAL
BI-DIRECTIONAL
TRANSFORMER
LINE
K4
1
OUTPUT
NEUTRAL
GRID
LINE
GRID
GND
GRID
NEUTRAL
GEN
LINE
GEN
GND
GEN
NEUTRAL
AC OUTPUT
LINE
OUTPUT
GND
9
4
6
3
7
K2
1
9
4
6
3
7
K3
1
9
4
6
3
7
INVERTING
CHARGING
METAL CHASSIS
GROUND OF THE UNIT
QD