Description
Engineered for high-density voltage acquisition within the Honeywell MasterLogic PLC platform, the Honeywell 2MLF-AV8A analog input module provides robust signal processing for industrial automation environments. This module interfaces seamlessly with field-level voltage instrumentation, converting analog signals into highly precise digital registers for the controller. With its high-speed conversions and dense channel packaging, it is ideal for systems demanding fast response times and compact panel space.
Features
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8 Voltage Input Channels: High-density processing in a single module footprint to minimize rack space.
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Fast Conversion Speed: Achieves a digital conversion rate of 250 microseconds per channel.
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Electrical Protection: Photo-coupler isolation between input terminals and PLC power supply protects sensitive control logic.
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Flexible Addressing: Supports both fixed I/O mapping (64 points) and variable mapping (16 points) to optimize backplane data exchange.
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Secure Field Wiring: Equipped with an 18-point detachable terminal block for straightforward field maintenance.
Applications
- Power plant auxiliary process monitoring
- Water and wastewater flow and pressure telemetry
- Factory automation assembly and testing lines
- Oil and gas storage tank level monitoring
Technical Specifications
| Parameter |
Specification Value |
| Manufacturer |
Honeywell |
| Model Code |
2MLF-AV8A |
| Module Type |
Analog Input Module (Voltage) |
| Number of Channels |
8 Channels |
| Maximum Conversion Speed |
250 us / channel |
| Absolute Maximum Input |
+/-15V |
| Isolation Method |
Photo-coupler isolation (Terminals to PLC internal power); No isolation between channels |
| Terminal Interface |
18-point terminal block |
| I/O Addresses Assigned |
Fixed type: 64 points / Variable type: 16 points |
| Internal Current Consumption |
420 mA at 5VDC |
| Net Weight |
0.14 kg |
| Shipping Weight (Calculated) |
2.00 kg |
Empirical Engineering Insights
Alternative Models & Compatibility
The 2MLF-AV8A is specifically designed for voltage signals. If your field loops utilize 4-20mA or 0-20mA current signals, you must use the 2MLF-AC8A current input module instead. Using inline shunt resistors on the 2MLF-AV8A to measure current signals is not recommended as it bypasses the design specifications and degrades overall loop accuracy.
Application Pitfalls & Engineering Notes
Note that while there is strong photo-coupler isolation between the field terminals and the PLC backplane, there is no isolation between individual channels. If your analog inputs come from different physical locations with different ground potentials, you will experience ground loops. These loops will corrupt your measurement data and potentially damage the module. Use external signal isolators for loops with distinct ground potentials.
Commissioning & Wiring Tips
To minimize high-frequency noise from nearby variable frequency drives (VFDs) or motor contactors, always run analog input cables inside dedicated, grounded metal conduits separated from high-voltage AC cables. Connect the cable shield to the cabinet’s single-point ground system on the PLC end only, leaving the field end ungrounded to prevent circulating shield currents.
Installation Guidelines
CRITICAL WARNING
Disconnect all power sources to the PLC rack and field wiring terminals before installing, removing, or servicing this module. Hot-swapping the 2MLF-AV8A may cause backplane communications faults, damage internal components, or disrupt active processes.
1
Ensure the MasterLogic PLC backplane is completely de-energized.
2
Align the module guides with the targeted slot on the backplane, slide the module firmly into place, and engage the locking mechanisms.
3
Wire the analog voltage inputs to the 18-point terminal block according to your system wiring diagram, ensuring correct polarity.
4
Attach the pre-wired terminal block to the front of the module and tighten the retaining screws to prevent vibration displacement.