Siemens simatic et200sp User Manual

Wiring
3.3 Current transformer selection data
Analog input module AI Energy Meter 480VAC ST (6ES7134-6PA20-0BD0)
Manual, 12/2015, A5E36061895-AA
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3.3
Current transformer selection data
Introduction
Connection via a current transformer is always required for the current measurement. Use
toroids with an accuracy class of 0.5, 1 or 3.
Dimensioning of the current transformer
The correct dimensioning of the current transformer is important for the following reasons:
● You achieve correct results from the measurements and
● You do not overload or damage the current transformers.
Selecting a current transformer
Use current transformers with a burden capacity 1.5 to 2 times greater than the power
dissipation in the terminal circuit (consisting of resistance of the connection cables and
burden of energy meter). 1.5 times the power loss is required in order to prevent the
transformer from overloading. 2 times the power dissipation is important to ensure the
current limiting in case of a short-circuit.

Siemens simatic et200sp Specifications

General

Category	I/O Systems
Power Supply	24 V DC
Protection Rating	IP20
Number of Modules	Up to 64 modules
Mounting	DIN Rail
Communication Protocols	PROFINET, PROFIBUS
Storage Temperature	-40 °C to +70 °C
Digital Inputs	Yes (depending on module)
Digital Outputs	Yes (depending on module)
Analog Inputs	Yes (depending on module)
Analog Outputs	Yes (depending on module)
Modularity	Modular
Relative Humidity	5 to 95% (non-condensing)
Weight	Varies by configuration
System Type	Distributed I/O