Cable Connection Description
Precautions
- Before connecting the DC input power cable, ensure that the DC voltage is within the safe range (lower than 60 V DC) and that the three DC switches on the solar inverter are set to OFF. Failing to do so may result in electric shocks.
- If you turn a DC SWITCH to ON by mistake when connecting or disconnecting DC input power cables, do not remove or insert DC input terminals. If you need to remove or insert a DC input terminal, perform the operations provided in Power-Off for Troubleshooting.
- When the solar inverter operates in grid-tied mode, do not perform maintenance or operations on the DC circuit, such as connecting or disconnecting a PV string or a PV module in the PV string. Failing to do so may cause electric shocks or arcing, which may also cause fire.
- The open-circuit voltage of each PV string must be 1100 V DC or lower under any circumstances.
- The polarities of electric connections are correct on the DC input side. The positive and negative terminals of a PV module connect to corresponding positive and negative DC input terminals of the solar inverter.
- Ensure that the PV module output is well insulated to ground.
- The PV strings connecting to the same MPPT circuit should contain the same number of identical PV modules.
- The solar inverter does not support full parallel connection for PV strings (full parallel connection: PV strings connect to one another in parallel outside the solar inverter and then connect to the solar inverter separately).
- During the installation of PV strings and the solar inverter, the positive or negative terminals of PV strings may be short-circuited to ground if the power cable is not properly installed or routed. In this case, an AC or DC short circuit may occur and damage the solar inverter. The caused device damage is not covered under any warranty.
Terminal Description
The solar inverter has 20 DC input terminals. DC SWITCH 1 controls PV1–PV8 (MPPT1–MPPT4), DC SWITCH 2 controls PV9–PV14 (MPPT5–MPPT7), and DC SWITCH 3 controls PV15–PV20 (MPPT8–MPPT10).
When the DC input is not fully configured, the DC input terminals must meet the following requirements:
- Evenly distribute the DC input power cables on the DC input terminals controlled by the three DC switches. DC SWITCH 1 is preferred.
- Maximize the number of connected MPPT circuits.
For example, if the number of input routes is 1–19, the DC input terminals are selected as follows.
Number of PV Strings |
Terminal Selection |
Number of PV Strings |
Terminal Selection |
|---|---|---|---|
1 |
Any even-numbered route |
2 |
PV2 and PV10 |
3 |
PV2, PV10, and PV18 |
4 |
PV2, PV6, PV10, and PV18 |
5 |
PV2, PV6, PV10, PV14, and PV18 |
6 |
PV2, PV4, PV6, PV10, PV14, and PV18 |
7 |
PV2, PV4, PV6, PV10, PV14, PV18, and PV20 |
8 |
PV2, PV4, PV6, PV8, PV10, PV14, PV18, and PV20 |
9 |
PV2, PV4, PV6, PV8, PV10, PV14, PV16, PV18, and PV20 |
10 |
PV2, PV4, PV6, PV8, PV10, PV12, PV14, PV16, PV18, and PV20 |
11 |
PV1, PV2, PV4, PV6, PV8, PV10, PV12, PV14, PV16, PV18, and PV20 |
12 |
PV1, PV2, PV4, PV6, PV8, PV10, PV12, PV14, PV16, and PV18–PV20 |
13 |
PV1–PV4, PV6, PV8, PV10, PV12, PV14, PV16, and PV18–PV20 |
14 |
PV1–PV4, PV6, PV8, PV10, PV12, PV14, and PV16–PV20 |
15 |
PV1–PV6, PV8, PV10, PV12, PV14, and PV16–PV20 |
16 |
PV1–PV6, PV8, PV10, PV12, and PV14–PV20 |
17 |
PV1–PV8, PV10, PV12, and PV14–PV20 |
18 |
PV1–PV8, PV10, and PV12–PV20 |
19 |
PV1–PV10 and PV12–PV20 |
N/A |
N/A |