AAI143-H53/A4D00

The Yokogawa AAI143-H53/A4D00 is a 16-channel isolated analog input module for receiving 4-20 mA DC signals from field transmitters. It supports HART digital communication for instrument data access and combines the H53 module configuration with an A4D00 dual pressure clamp terminal block. The module also includes the ISA Standard G3 option and an extended operating temperature configuration.

Functional Description

The AAI143 receives analog current signals from 2-wire or 4-wire transmitters and converts them into digital input data for the control system. Its 16 input channels support process-variable acquisition, allowing multiple field instruments to connect through one I/O module.

The HART communication function allows supported smart transmitters to exchange digital instrument information over the 4-20 mA signal loop. This provides access to additional device information beyond the primary analog process value.

Input Configuration and Signal Characteristics

The module accepts standard 4-20 mA DC input signals, with an allowable input current of up to 24 mA. The input resistance varies with the signal current when the module is powered, affecting the voltage available to the connected transmitter.

Each channel can be configured for a 2-wire or 4-wire transmitter using the module setting pin. For 2-wire transmitters, the module provides a transmitter supply with a specified output current limit. External wiring voltage drop must be considered when checking the minimum operating voltage at the field instrument.

Isolation and Electrical Performance

The AAI143 provides isolation between the field input and the control system, with a withstand voltage of 1500 V AC for 1 minute under the specified pressure-clamp connection configuration. This isolation helps separate field-side electrical conditions from the system-side circuitry.

The 10 ms data update period supports regular acquisition of changing process signals. The specified accuracy is ±16 uA, while ambient-temperature-related drift is ±16 uA per 10 deg C. These values are relevant when evaluating measurement accuracy across the module's operating temperature range.

Model Suffix and Terminal Configuration

The ordering code identifies the following configuration:

• AAI143: 16-channel isolated analog input module for 4-20 mA signals.
• -H: HART digital communication support.
• 5: Configuration without explosion protection.
• 3: ISA Standard G3 option and extended temperature option (-20 to 70 deg C).
• /A4D00: Dual pressure clamp terminal block option, associated with terminal block model ATA4D-00.

The A4D00 option identifies the field termination arrangement. It should not be interpreted as proof of dual-redundant module operation. The terminal configuration and module redundancy are separate selection considerations.

Technical Specifications

Parameter	Specification
Model	AAI143-H53/A4D00
Brand	Yokogawa
Product Type	Analog Input Module
Input Signal	4-20 mA DC
Number of Input Channels	16
Channel Configuration	Isolated
HART Communication	Supported
Allowable Input Current	24 mA
Input Resistance (Power ON)	270-350 ohm
Input Resistance (Power OFF)	500 kohm or higher
Accuracy	±16 uA
Data Update Period	10 ms
Withstand Voltage	1500 V AC for 1 minute (input to system, pressure-clamp connection)
Transmitter Power Supply	19.0 V or higher at 20 mA; 25.5 V or lower at 0 mA
Transmitter Supply Current Limit	25 mA
Transmitter Configuration	2-wire or 4-wire, selectable per channel
Temperature Drift	±16 uA/10 deg C
Maximum Current Consumption	230 mA (5 V DC); 540 mA (24 V DC)
Terminal Configuration	Dual pressure clamp terminal block
Terminal Block Model	ATA4D-00
Environmental Option	ISA Standard G3
Operating Temperature Option	-20 to 70 deg C
Weight	0.3 kg

Frequently Asked Questions

Q: Does the AAI143-H53/A4D00 support HART communication?

A: Yes. The -H suffix identifies the HART communication configuration. It supports digital communication with compatible HART field instruments while acquiring their 4-20 mA analog signals.

Q: What is the function of the A4D00 option?

A: The /A4D00 option specifies a dual pressure clamp terminal block, identified as ATA4D-00. It defines the field wiring termination configuration rather than the module's input channel count or redundancy status.

Q: Can this module be used directly in an intrinsically safe application?

A: The H53 configuration specifies no explosion protection. Yokogawa's AAI143 specifications also state that a Zener barrier cannot be connected directly to this module. An appropriate isolation barrier is required when using it in an intrinsically safe application.

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