Yokogawa AMM42 2-Wire Transmitter Input Multiplexer Module
The Yokogawa AMM42, also cataloged as the AMM42 2-Wire Transmitter Input Multiplexer Module, operates as a dedicated hardware component for multiplexed analog signal acquisition and field transmitter power distribution within industrial DCS networks.
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | AMM42 |
| Brand | Yokogawa |
| Origin | Japan |
| Weight | 0.65 lbs |
| Dimensions | Not specified in source data |
| Operating Temp | Not specified in source data |
| Power Consumption | 4 A or less (5.0 VDC) |
| Input Signal | -4 to 20 mA DC |
| Allowable Input Voltage | 40 mA or less |
| Transmitter Power Supply | 23.5 to 24.5 VDC (output limit: 60 mA or less) |
| Input Resistance | 250 ohm (configurable to 70 ohm with barrier) |
| Signal Isolation | None (system-to-field or channel-to-channel) |
| Data Update Period | 1 second |
Channel-to-Channel Isolation and 4-20 mA HART Loop Protocol
This multiplexer module handles multiple 2-wire transmitter inputs, accepting -4 to 20 mA DC signals with an allowable limit of 40 mA or less. The module provides a dedicated transmitter power supply output of 23.5 to 24.5 VDC, limited to 60 mA or less per channel to prevent field loop overcurrent. The nominal input resistance is 250 ohm, which can be reduced to 70 ohm when interfacing with intrinsic safety barriers to maintain proper loop voltage compliance. Channel-to-channel isolation is not provided between individual input channels or between the system and field circuits, requiring external galvanic isolation barriers when ground loops or hazardous area compliance is required. The 4-20 mA HART loop protocol is supported for digital diagnostic communication overlaid on the analog current signal. Data update occurs at a period of 1 second across all multiplexed channels.
Frequently Asked Questions (FAQ)
Q: What is the transmitter power supply output specification of the AMM42 module?
A: The AMM42 provides a 23.5 to 24.5 VDC transmitter power supply with an output current limit of 60 mA or less per channel.
Q: Can the input resistance be adjusted for barrier-connected applications?
A: Yes, the input resistance is 250 ohm by default and can be changed to 70 ohm when connected to an intrinsic safety barrier to maintain adequate loop voltage.
Q: Does this module provide channel-to-channel galvanic isolation?
A: No, the AMM42 does not provide signal isolation between the system and field or between individual channels. External isolation barriers are required for ground loop prevention or hazardous area compliance.
Field Installation Guidelines
Mount the AMM42 module in the designated slot position per the DCS hardware manual. Ensure the backplane power supply is de-energized before inserting or removing the module. Route 2-wire transmitter cables in shielded twisted-pair configuration with the shield grounded at the DCS cabinet only. Verify input resistance jumper settings match the application requirements (250 ohm for direct connection, 70 ohm for barrier-connected loops). Confirm transmitter power supply voltage is within the 23.5 to 24.5 VDC range before connecting field devices. Perform loop current verification on each multiplexed channel prior to commissioning. When using intrinsic safety barriers, verify barrier certification and wiring compliance with the approved hazardous area drawing. Maintain adequate clearance around the module for thermal dissipation given the 4 A or less backplane current draw.
Yokogawa AMM42 2-Wire Transmitter Input Multiplexer Module
Yokogawa AMM42 2-Wire Transmitter Input Multiplexer Module
The Yokogawa AMM42, also cataloged as the AMM42 2-Wire Transmitter Input Multiplexer Module, operates as a dedicated hardware component for multiplexed analog signal acquisition and field transmitter power distribution within industrial DCS networks.
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | AMM42 |
| Brand | Yokogawa |
| Origin | Japan |
| Weight | 0.65 lbs |
| Dimensions | Not specified in source data |
| Operating Temp | Not specified in source data |
| Power Consumption | 4 A or less (5.0 VDC) |
| Input Signal | -4 to 20 mA DC |
| Allowable Input Voltage | 40 mA or less |
| Transmitter Power Supply | 23.5 to 24.5 VDC (output limit: 60 mA or less) |
| Input Resistance | 250 ohm (configurable to 70 ohm with barrier) |
| Signal Isolation | None (system-to-field or channel-to-channel) |
| Data Update Period | 1 second |
Channel-to-Channel Isolation and 4-20 mA HART Loop Protocol
This multiplexer module handles multiple 2-wire transmitter inputs, accepting -4 to 20 mA DC signals with an allowable limit of 40 mA or less. The module provides a dedicated transmitter power supply output of 23.5 to 24.5 VDC, limited to 60 mA or less per channel to prevent field loop overcurrent. The nominal input resistance is 250 ohm, which can be reduced to 70 ohm when interfacing with intrinsic safety barriers to maintain proper loop voltage compliance. Channel-to-channel isolation is not provided between individual input channels or between the system and field circuits, requiring external galvanic isolation barriers when ground loops or hazardous area compliance is required. The 4-20 mA HART loop protocol is supported for digital diagnostic communication overlaid on the analog current signal. Data update occurs at a period of 1 second across all multiplexed channels.
Frequently Asked Questions (FAQ)
Q: What is the transmitter power supply output specification of the AMM42 module?
A: The AMM42 provides a 23.5 to 24.5 VDC transmitter power supply with an output current limit of 60 mA or less per channel.
Q: Can the input resistance be adjusted for barrier-connected applications?
A: Yes, the input resistance is 250 ohm by default and can be changed to 70 ohm when connected to an intrinsic safety barrier to maintain adequate loop voltage.
Q: Does this module provide channel-to-channel galvanic isolation?
A: No, the AMM42 does not provide signal isolation between the system and field or between individual channels. External isolation barriers are required for ground loop prevention or hazardous area compliance.
Field Installation Guidelines
Mount the AMM42 module in the designated slot position per the DCS hardware manual. Ensure the backplane power supply is de-energized before inserting or removing the module. Route 2-wire transmitter cables in shielded twisted-pair configuration with the shield grounded at the DCS cabinet only. Verify input resistance jumper settings match the application requirements (250 ohm for direct connection, 70 ohm for barrier-connected loops). Confirm transmitter power supply voltage is within the 23.5 to 24.5 VDC range before connecting field devices. Perform loop current verification on each multiplexed channel prior to commissioning. When using intrinsic safety barriers, verify barrier certification and wiring compliance with the approved hazardous area drawing. Maintain adequate clearance around the module for thermal dissipation given the 4 A or less backplane current draw.
