SAI143-S53/A4S00

The Yokogawa SAI143-S53/A4S00 is a 16-channel analog input module designed to receive 4-20 mA current signals from field transmitters. It provides module isolation, individual channel selection for 2-wire or 4-wire transmitter connections, and configurable transmitter power supply control. This version uses a pressure clamp terminal block and has ISA Standard G3 environmental specifications.

Functional Description

The SAI143-S53/A4S00 converts field current signals into input data for the control system. Its 16 input channels support a rated range of 4-20 mA, with a permissible input range of 0-25 mA. Module isolation separates the input signal circuits from the system side, with a specified withstand voltage of 1.5 kV AC for one minute.

The module has a data update frequency of 40 ms. This determines how frequently updated input values are made available to the control system and should be considered when evaluating process signal response requirements.

Transmitter Connection and Power Supply

Each channel can be configured individually for 2-wire or 4-wire transmitter operation through setting pins. For 2-wire transmitters, the module provides loop power, with a minimum supply voltage of 16.15 V at 20 mA and a maximum of 26.4 V at 0 mA. The output current limit is 25 mA.

The transmitter power supply ON/OFF function is available in 2-wire mode. It operates across all 16 channels simultaneously rather than providing independent power switching for each channel. This distinction is relevant when planning transmitter power isolation and maintenance procedures.

Input Accuracy and Electrical Characteristics

For the standard SAI143-S version, the rated accuracy is +/-16 uA over an input range of 1-23 mA. Temperature drift is specified as +/-16 uA per 10 deg C. The accuracy range should be distinguished from the module's wider permissible input range of 0-25 mA.

During power-on, the input impedance is specified as 250 ohms plus the voltage drop in the module's internal input protection circuit. During power-off, the input impedance is at least 500 kohms. These characteristics affect the electrical loading seen by connected field transmitters.

Model Configuration and Terminal Block

The ordering code identifies the hardware configuration:

Code	Description
SAI143	4-20 mA, 16-channel isolated analog input module
-S	Standard type
5	Pressure clamp terminal block or MIL cable configuration, without explosion protection
3	ISA Standard G3 and operating temperature range of -20 to 70 deg C
/A4S00	Pressure clamp terminal block for analog signals, model STA4S-00

The complete order code SAI143-S53/A4S00 therefore identifies the standard, non-explosion-protected module with ISA G3 environmental specifications and a pressure clamp terminal block. The terminal block option is STA4S-00.

Technical Specifications

Parameter	Specification
Model	SAI143-S53/A4S00
Brand	Yokogawa
Product Type	Analog Input Module
Number of Input Channels	16
Input Type	4-20 mA
Rated Input Range	4-20 mA
Permissible Input Range	0-25 mA
Input Isolation	Module isolation
Rated Accuracy	+/-16 uA (1-23 mA input range)
Data Update Frequency	40 ms
Temperature Drift	+/-16 uA/10 deg C
Input Impedance (Power-ON)	250 ohms + voltage drop in internal input protection circuit
Input Impedance (Power-OFF)	500 kohms minimum
Transmitter Power Supply	16.15 V minimum at 20 mA; 26.4 V maximum at 0 mA
Transmitter Supply Current Limit	25 mA
Transmitter Configuration	Individually selectable 2-wire or 4-wire
Transmitter Power ON/OFF	Available in 2-wire mode; all 16 channels switched simultaneously
Withstand Voltage	1.5 kV AC between input signal and system for 1 minute
Maximum Current Consumption	320 mA (5 V system); 550 mA (24 V system)
External Connection	Pressure clamp terminal block
Terminal Block Model	STA4S-00
Environmental Specification	ISA Standard G3
Operating Temperature	-20 to 70 deg C
Weight	0.34 kg

Frequently Asked Questions

Q: Does the SAI143-S53/A4S00 support HART communication?

A: No. The -S designation identifies the standard version. HART communication is associated with the SAI143-H version and should not be assumed for this model.

Q: Can the module support both 2-wire and 4-wire transmitters?

A: Yes. Each input channel can be configured individually for 2-wire or 4-wire operation using setting pins. However, the transmitter power supply ON/OFF function is available only in 2-wire mode and switches all 16 channels simultaneously.

Q: Is the STA4S-00 terminal block included in this configuration?

A: Yes. The /A4S00 option specifies the analog pressure clamp terminal block STA4S-00. This ordering configuration should be distinguished from versions supplied for MIL cable connections or signal cable interface adapters.

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