Huawei SUN2000-33KTL-JP, User Manual

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SUN2000-(33KTL, 40KTL)-JP
User Manual
6 Electrical Connections (12-pin Spot-Check Terminal)
Issue 07 (2019-06-30) Copyright © Huawei Technologies Co., Ltd. 76
 Before connecting DC input power cables, ensure that the DC voltage is within the safe
range (lower than 60 V DC) and that the two DC switches on the SUN2000 are OFF.
Otherwise, the high voltage may result in electric shocks.

When the SUN2000 is grid-tied, it is not allowed to maintain DC input power cables, such
as connect or disconnect a string or a module in a string. Otherwise, electric shocks may
occur.
Ensure that the following conditions are met. Otherwise, the SUN2000 will be damaged, or
even a fire disaster will be caused.

The open-circuit voltage of each PV string is always lower than or equal to 1100 V DC.

The positive and negative terminals of a PV module connect to the positive and negative
DC input terminals of the SUN2000 respectively.
 If the DC input power cable is reversely connected, do not operate the DC switches and
positive and negative connectors immediately. Wait until the solar irradiance declines at
night and the PV string current reduces to below 0.5 A. Then, turn off the two DC switches,
remove the positive and negative connectors, and rectify the connection of the DC input
power cable.

Ensure that the PV module output is well insulated to ground.

During the installation of PV strings and SUN2000, the positive or negative terminals of
PV strings may be grounded if power cables are not properly installed or routed. In this
case, an AC or DC short circuit may occur and damage the SUN2000. The caused
equipment damage is beyond the warranty scope.
The PV strings must meet the following requirements if they need to be grounded:

A three-phase isolation transformer is installed on the output side.
 One isolation transformer must be installed only for one SUN2000. Do not connect two or more
SUN2000s to the same isolation transformer. Otherwise, the SUN2000s may fail to work due to the
loop current generated between them.

Set Isolation to Input grounded, with TF on the SUN2000 app, SmartLogger, or NMS.
Context

DC terminal selection
Figure 6-12 shows the DC terminals at the bottom of the SUN2000. Table 6-2 shows the
requirements for selecting DC terminals.
The SUN2000 provides two DC switches, namely, DC SWITCH 1 and DC SWITCH 2. DC SWITCH 1
controls the first to the fourth routes of DC input terminals, while DC SWITCH 2 controls the fifth to
the eighth routes of DC input terminals.