CPS SCA25KTL-DO/US-208 - Schematic Diagram and Circuit Design

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2.6 Schematic Diagram and Circuit Design
The basic electrical schematic diagram of the CPS SCA 25KTL-DO/US-208
3-Phase String Inverters are shown in Error! Reference source not
found.. The input from PV source circuits passes through surge protection
circuitry, DC EMI wave filters, and independent DC-DC boost circuitry to
achieve maximum power point tracking and boost the voltages to a common
DC bus. The inverter uses line voltage and frequency measurements to
synchronize to the grid and converts the available PV energy to AC power
by injecting balanced 3-phase AC current into the electric utility grid. Any
high frequency AC component is removed by passing through a two-stage
relay and EMI wave filter to produce high quality AC power.
WIRE BOX INVERTER POWER HEAD
L1
L2
L3
N
PV1+
PV1+
PV1-
PV1-
MPPT1
MPPT2
AC
Output
PV Input
PV2+
PV2+
PV2-
PV2-
AC
Switch
Fuses
MPPT3
PV3+
PV3+
PV3-
PV3-
DC SPD
PV1+
DC Switch
Three
level
inverter
AFD
PV2+
PV3+
PV-
PE
Type Ⅲ MOV
Transmitter
Vin
GND
AC/DC Power
Supply
Figure 2-3 CPS SCA25KTL-DO/US-208 Inverter Schematic, RSD Wire-box
The Rapid Shutdown wirebox has been designed specifically for
2017/2020 NEC Rapid Shutdown applications. This wirebox includes a
powerline communications transmitter for use with APS RSD-S-PLC/RSD-D
products. The integrated PLC transmitter is powered by AC at the inverter
output. This PLC transmitter sends a “keep alive” signal to the MLPE devices