MVI56-LTQ PROSOFT

Model: MVI56-LTQ
Brand: ProSoft Technology
Series: ControlLogix Platform (MVI56)
Core Function: Specialized flow computer for liquid turbine meters and pulse transmitters
Type: 8-Channel High-Speed Flow Interface
Key Specs: 8 Pulse Inputs, 5,000-word Database, Backplane Powered
Condition: New Original (New Surplus), not refurbished

Product Introduction

The ProSoft MVI56-LTQ is a specialized flow computer designed to reside directly within a Rockwell Automation ControlLogix chassis. Unlike standard high-speed counter cards, the LTQ (Liquid Turbine Quality) module is purpose-built to calculate compensated flow rates from turbine meters and pulse transmitters, adhering to strict custody transfer and process monitoring standards.

In my experience with oil and gas or chemical processing skids, the MVI56-LTQ is selected specifically to offload the heavy mathematical lifting of flow compensation from the main Logix CPU. It provides eight independent channels, each capable of processing high-frequency pulse data to generate instantaneous flow rates and accumulated totals directly into the processor’s tag database.

Key Selling Points & Differentiators

Hardware-Based Flow Computing: Performs complex liquid flow calculations internally, ensuring accuracy that isn’t dependent on PLC scan time or task priority.
8-Channel Density: Manages up to eight separate flow streams from a single slot, significantly reducing rack footprint compared to discrete counter/math combinations.
Custody Transfer Grade: Built-in support for API/AGA calculation methods, making it suitable for high-accuracy fiscal measurement applications.
Not Recommended For: Gas-phase ultrasonic or orifice plate measurements without verifying the specific MVI56-GSC or MVI56-AFC requirements; the LTQ is optimized for liquid pulse inputs.
Direct Backplane Integration: Passes data as native I/O to the ControlLogix processor, eliminating the latency and failure points of external flow computers.

Quality Transparency Strategy (QC SOP)

Incoming Inspection: We verify the revision of the pulse-processing daughterboard and inspect the 1756 backplane connector for any pin misalignment or environmental corrosion.
Live Functional Test: Modules are mounted in a 1756-A10 chassis. We use a precision function generator to inject 10 kHz pulse signals into each of the 8 channels to verify counter accuracy.
Logic Validation: Using the ProSoft Configuration Builder (PCB) and a test PLC, we confirm that the internal database correctly maps pulse counts to flow rate floating-point tags.
Electrical Parameter Tests: We verify the 800 mA current draw at 5.1 V DC to ensure the module’s internal DC-DC converters are operating within specification.
Firmware Verification: We record the specific firmware version (e.g., v1.08). Because flow calculations are version-sensitive, we can provide the specific “G-File” or AOI required for your revision.
Final QC + Packaging: Each unit is sealed in an ESD-safe moisture barrier bag and packed in reinforced cushioning to protect the sensitive pulse-input electronics.