ASI133-H00/ATSA3S

The Yokogawa ASI133-H00/ATSA3S is an 8-channel analog input module with a built-in barrier, designed to acquire isolated 4-20 mA field signals. It supports HART communication and is supplied with the ATSA3S pressure-clamp terminal block. The module combines analog signal acquisition with transmitter communication for integration into Yokogawa field control I/O systems.

Functional Description

The ASI133-H00 receives 4-20 mA signals from connected field transmitters and converts the measured current into input data for the control system. Its eight input channels support simultaneous acquisition of process variables such as pressure, flow and temperature when the connected transmitters provide compatible current outputs.

The built-in barrier provides electrical isolation between the field interface and the system side. This arrangement is intended for field signal interfacing where barrier protection is required. The module is specified for ISA Standard G3 compatibility and an extended operating temperature option.

HART Communication

The -H suffix identifies the HART communication version. In addition to the conventional 4-20 mA process signal, HART communication allows compatible field-device information to be exchanged over the analog loop. This provides access to supported transmitter data without treating the module as a conventional analog-only input.

Input Characteristics and Performance

Each channel accepts a 4-20 mA current signal, with an allowable input current of 22.5 mA. The specified measurement accuracy is +/-16 uA, while the 100 ms step response time defines the module's response to changes in the input signal. The 10 ms data update period determines how frequently updated input data is made available to the control system.

The module supports both 2-wire and 4-wire transmitter connections. For 2-wire transmitters, it provides a transmitter supply of at least 16 VDC, with an output current limit of 20 mA. The maximum normal-mode input voltage applied by a 4-wire transmitter is 25 V.

Terminal Block and Signal Connections

The ATSA3S is the single-configuration pressure-clamp terminal block specified for the ASI133. It provides field wiring connections for the module's eight input channels.

For reference, Yokogawa identifies ATSA3D as the corresponding dual-redundant terminal block. ATSA3S and ATSA3D therefore represent different connection configurations and should not be treated as interchangeable ordering codes.

Isolation and Environmental Conditions

The built-in barrier provides galvanic isolation between the field interface and the system side. However, the module does not provide channel-to-channel isolation. This distinction is important when evaluating grounding arrangements and field wiring, particularly when multiple channels connect to different field circuits.

The module specification includes ISA S71.04 Class G3 compliance and an ambient operating temperature range of -20 to 70 deg C. Its intrinsic safety installation requirements depend on the applicable approval certificate, associated equipment and installation conditions.

Technical Specifications

Parameter	Specification
Model	ASI133-H00/ATSA3S
Brand	Yokogawa
Product Type	Analog Input Module with Built-In Barrier
Input Channels	8
Input Signal	4-20 mA
Allowable Input Current	22.5 mA
Input Accuracy	+/-16 uA
Input Resistance (2-wire, Power ON)	400 ohm at 20 mA to 750 ohm at 4 mA
Input Resistance (4-wire, Power ON)	485 ohm at 20 mA to 925 ohm at 4 mA
Input Resistance (Power OFF)	1 Mohm or larger
Withstanding Voltage	1500 VAC
Step Response Time	100 ms
Data Update Period	10 ms
Transmitter Power Supply	16 VDC or higher
Transmitter Supply Current Limit	20 mA
Maximum Normal-Mode Input Voltage (4-wire)	25 V
Temperature Drift	+/-16 uA/10 deg C
Maximum Current Consumption	150 mA (5 VDC), 450 mA (24 VDC)
HART Communication	Available
Barrier Type	Isolated Interface
Terminal Block	ATSA3S, Pressure Clamp Terminal
Operating Temperature	-20 to 70 deg C
Environmental Compliance	ISA S71.04 Class G3
Weight	0.3 kg

Frequently Asked Questions

Q: Does the ASI133-H00/ATSA3S support HART communication?

A: Yes. The -H suffix identifies the HART communication version. It supports communication with compatible HART field devices alongside the conventional 4-20 mA process signal. For installation on an ER bus node with HART functionality, Yokogawa specifies EB401 firmware revision 2 or later.

Q: Does the module provide isolation between all eight input channels?

A: No. The module provides galvanic isolation between the field interface and the system side, but not between individual channels. This distinction should be considered when checking field grounding and wiring arrangements.

Q: Can ATSA3S be used for a dual-redundant configuration?

A: ATSA3S is the single-configuration terminal block. Yokogawa specifies ATSA3D for dual-redundant connections involving two adjacent I/O modules. The terminal block must match the intended system configuration. 

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