Siemens SIMATIC 6ES7134-4FB01-0AB0

The Siemens SIMATIC ET 200S 2AI U ST analog electronic module (6ES7134-4FB01-0AB0) is a distributed I/O component designed for acquiring continuously variable analog signals, such as those from temperature or resistance measurements, and converting them into digital values for further processing within an automation system. This manual, dated April 2007, provides comprehensive information for commissioning and operating the module, supplementing the general ET 200S Distributed I/O System Operating Instructions.

Function Description

The 2AI U ST analog electronic module features two inputs for measuring voltage. It supports several input ranges: ±10 V, ±5 V, and 1 V to 5 V, all with a resolution of 13 bits plus sign. The module is electrically isolated from the load voltage L+, and also between its channels and the backplane bus, as well as between the channels and the load voltage L+. However, there is no electrical isolation directly between the channels themselves. The permissible common mode voltage (UCM) between the inputs and MANA is 2 VACSS, and between MANA and the central grounding point (UISO) is 75 VDC / 60 VAC. The module is designed for an extended temperature range from 0 to 50°C when installed vertically.

Analog values are represented in two's complement, with the sign (S) always in bit number 15. The module offers digital filtering for smoothing measured values, adjustable in four steps: None, Weak, Medium, and Strong. The smoothing factor (k) multiplied by the module's cycle time determines the time constant of the filter. A higher smoothing factor results in a greater time constant.

The module supports various diagnostic functions. A red "SF" LED indicates group errors, which can include parameter assignment errors, internal errors, or issues with the load voltage. Specific diagnostic messages are readable, covering conditions like overflow/underflow, wire breaks (for the 1 to 5 V measuring range), upper limit exceeded, lower limit value undershot, and open circuits.

Important Technical Specifications

Dimensions and Weight:
- Width: 15 mm
- Weight: Approx. 40 g
Inputs:
- Number of inputs: 2
- Input ranges: ±10 V, ±5 V, 1 V to 5 V
- Resolution: 13 bits + sign for all ranges
- Input resistance: 100 kΩ for all voltage ranges
- Permitted input voltage (destruction limit): 35 V continuous, 75 V at max. duration of 1 ms (sampling ratio 1:20)
Electrical Isolation:
- Between channels and backplane bus: Yes
- Between channels and load voltage L+: Yes
- Between channels: No
Permissible Potential Difference:
- Between inputs and MANA (UCM): 2 VACSS
- Between MANA and central grounding point (UISO): 75 VDC / 60 VAC
Power Supply:
- Rated load voltage L+ (from power module): 24 VDC
- Reverse polarity protection: Yes
- Current consumption from load voltage L+: Max. 30 mA
- Power dissipation: Typically 0.6 W
Analog Value Generation:
- Measuring principle: Integrative
- Integration time: Parameterizable (60 Hz / 16.7 ms or 50 Hz / 20 ms)
- Conversion time: 55 ms (60 Hz) / 65 ms (50 Hz)
- Cycle time: Number of active channels per module x conversion time
Interference Suppression and Error Limits:
- Common-mode interference suppression (Uss): Min. 90 dB
- Series-mode interference suppression: Min. 70 dB
- Crosstalk between inputs: Min. -50 dB
- Operational limit: ±0.6% (over entire temperature range)
- Basic error limit (at 25°C): ±0.4%
- Temperature error: ±0.01%/K
- Linearity error: ±0.01%
- Repeatability (steady state at 25°C): ±0.05%
Cable Length: Max. 200 m (shielded)

Usage Features

The module is designed for ease of integration into the ET 200S distributed I/O system. It requires basic knowledge of automation engineering for setup and operation. Commissioning and operation should only be performed by qualified personnel.

Terminal Assignment: The manual provides a detailed terminal assignment for connecting measuring sensors. Terminals include M0+, M0-, M1+, M1- for input signals, MANA for module ground, and AUX1 for protective-conductor or potential bus connections.
Terminal Modules: The module is compatible with various terminal modules (e.g., TM-E15C26-A1, TM-E15S26-A1, TM-E15N26-A1) which offer different connection types such as spring, screw-type, or Fast Connect terminals.
Wiring: Shielded and twisted-pair cables are recommended for analog signals to minimize interference. Shields should be grounded at both ends, or at one end if potential differences between cable ends cause equipotential bonding currents that interfere with signals.
Connecting Measuring Encoders:
- Isolated Measuring Encoders: These are potential-free and not connected to local ground. For the 2AI U analog input module, M- should be connected to MANA to ensure the permitted UCM value is not exceeded, especially in environments with strong EMC interference.
- Non-isolated Measuring Encoders: These are connected to local ground potential. MANA must be connected to the ground potential. If the permitted UCM value is exceeded, equipotential bonding conductors must be used between measuring points.
Unused Channels: Unused input channels should be "deactivated" in the parameter assignment. A deactivated channel returns the value 7FFFH. Deactivating channels halves the module cycle time. Jumpers must be wired on the terminal module for unused channels to adhere to permissible potential differences (UCM).
Parameterization: Parameters such as group diagnostics (enable/disable), overflow/underflow diagnostics (enable/disable), wire break diagnostics (enable/disable, for 1 to 5 V range only), smoothing (None, Weak, Medium, Strong), and type/range of measurement (Deactivated, ±5 V, ±10 V, 1 to 5 V) can be configured.
Analog Value Representation: The manual includes tables detailing the binary, decimal, and hexadecimal representation of analog values for different measuring ranges (±5 V, ±10 V, 1 to 5 V), including overshoot and underrange values.
Operating State Effects: The input values depend on the supply voltage L+ and the operating state of the PLC (CPU of the DP master). For instance, during "POWER ON RUN" with L+ present, process values are read, but if L+ is missing, 7FFFH is returned.

Maintenance Features

Diagnostics: The "SF" LED provides a visual indication of group errors. If the LED is on, it suggests issues like incorrect configuration, an improperly plugged-in module, missing load voltage, or a diagnostic message. The remedy involves checking parameter assignment, load voltage, and evaluating specific diagnostic messages.
Error Types: The manual lists various error types with their meanings and suggested remedies. These include:
- Parameter assignment error (10000): Module cannot use the parameter for the channel (e.g., inserted module mismatch, incorrect parameter assignment). Remedy: Correct configuration or parameter assignment.
- Internal module error (01001): Remedy: Replace the module.
- Upper limit exceeded (00111): Value is above the overshoot range. Remedy: Correct module/final controlling element tuning.
- Lower limit value undershot (01000): Value is below the underrange. Remedy: Correct module/final controlling element tuning.
- Open circuit (00110): Line to the encoder interrupted. Remedy: Correct the process wiring.
Recycling and Disposal: The ET 200S module is recyclable due to its low contaminant content. For environmentally compliant recycling and disposal of electronic waste, users should contact a certified company.