SMA PPM-10 - Connecting the Current Transformer

6 Electrical Connection
SMA Solar Technology AG
Installation Manual 39PPM-10-IA-en-16
6.4.3 Connecting the Current Transformer
DANGER
Danger to life due to electric shock when live components or cables are touched
High voltages are present in the conductive components or cables of the product. Touching live parts and cables
results in death or lethal injuries due to electric shock.
• Do not touch non-insulated parts or cables.
• Before performing any work or opening the product, short-circuit the secondary circuits of the current
transformers through an external short circuit device, externally disconnect the supply voltage and cables for
the current and voltage measurement.
• Observe all safety information on components associated with the product.
• Wear suitable personal protective equipment for all work on the product.
• Always perform all work in accordance with the locally applicable standards, directives and laws.
• Cover or isolate all live components.
NOTICE
Damage to the current transformers due to high voltage peaks
If current flows in the primary circuit of a current transformer and the secondary circuit of the current transformer is
opened at the same time, a high voltage peak can occur. This voltage peak can result in damage to the current
transformer.
• Prior to disconnecting the current measurement at the product, short-circuit the secondary circuit of each current
transformer via an external short circuit device.
NOTICE
Damage of the gensets due to undetected reverse feeding when using summation current
transformers
When using a summation current transformer for the monitoring of several gensets, only the total current of all
gensets is recorded. The currents of the individual gensets can not be monitored and possible reverse feeding
therefore not be detected. Gensets can be damaged due to reverse feeding of electrical power.
If summation current transformers are used for the monitoring of several gensets, observe the following
requirements:
• Only use gensets with reverse power protection function that fulfill the reverse power limits of the product (see
Section10, page63).
• Activate the reverse power protection function of the gensets before commissioning the product (see
documentation of the genset manufacturer).
• Ensure that the reverse power protection function of the gensets is always active during operation of the
product.