OMNI 4000 Flow Computer (Compact 4-Slot Chassis)

Overview

The OMNI 4000 is the compact member of the current OMNI 4000/7000 flow computer platform from OMNI Flow Computers, Inc. of Sugar Land, Texas. It runs the same firmware, the same configuration software and the same front panel as the larger OMNI 7000, but it is built around a smaller chassis with four I/O module slots instead of ten. That makes it the natural choice for single-run and small multi-run metering skids, LACT units, truck and rail loading points, gas sales meters and allocation stations where a full ten-slot unit would carry hardware that is never used.

Seven Star LLC supplies the OMNI 4000 to metering contractors, pipeline operators and package builders in the Sultanate of Oman and across the GCC, with engineering support in Muscat. Many of our customers already run OMNI 3000 or OMNI 6000 units, and the OMNI 4000 gives them a modern, smaller replacement that keeps the familiar OMNI way of working.

Operating Principle

A flow computer reads the primary signals from a metering run and converts them into corrected, auditable quantities. In the OMNI 4000, pulse inputs from turbine, positive displacement or other pulse-output meters arrive at the back panel together with 4–20 mA or 1–5 V signals from pressure, temperature and differential pressure transmitters, four-wire 100 Ω RTDs and, where fitted, densitometer frequency signals. These inputs pass from the back panel terminal blocks into plug-in process I/O combo modules, are digitized and handed to the 32-bit CPU. According to the manufacturer, all time-critical measurement functions are performed every 500 milliseconds or less, while the digital multiplexer, pulse density and double chronometry functions run every 10 milliseconds.

The firmware contains liquid and gas calculations in both US and metric units. The installation guide lists API MPMS Chapter 11.1 volume correction for crude oil, refined products and lubricating oils, GPA TP-27 tables for LPG and NGL, mass calculation, AGA-3 and ISO 5167 for differential pressure meters, AGA-7 for pulse meters, AGA-8 and SGERG density methods, heating value per GPA 2172, AGA-5 and ISO 6976, and AGA-10 speed of sound. The result is a single device that totalizes, batches, proves and archives several meter runs at once, which is exactly what a custody transfer contract requires.

Engineering Design of the OMNI 4000

The OMNI 4000 motherboard has four I/O module slots, each tied to one terminal block on the back panel. In the standard factory order TB-1 carries the Digital I/O Multiplexer (DM) module, TB-2 a communication module and TB-3 and TB-4 process I/O modules. The DM module provides ten independent digital channels that can each be configured as an input or an output, the first four of which can be used for prover detector switches. The Dual Ethernet module adds two RJ-45 ports at 100 Mbps, and up to three external Digital Terminal boards with sixteen points each can extend discrete I/O for valves, samplers and injection pumps.

On the front of the OMNI 4000 sits a 4.3-inch color LCD with 800 × 480 resolution, a 25-key keypad with tactile and audio feedback, a dual-color alarm LED, a USB Mini-B port for configuration and a USB-A host port for firmware updates from a memory stick. Behind it, the CPU has 16 MB flash, 128 MB DDR2 SDRAM, 4 MB of non-volatile RAM that needs no battery, and an SD card with 8 GB available for historical records. Configuration and the 35 most recent daily and batch records are kept in that non-volatile memory, and older reports move to the SD card.

Key Features

The main features of this compact unit documented in the manufacturer’s installation guide are:

• Four I/O module slots in a compact chassis, using the same plug-in DM, Dual Ethernet, Serial and process I/O modules as the OMNI 7000.
• Support for up to six meter runs, each configurable for liquid or gas measurement independently, with two sets of detector switches for dual prover volumes.
• Plug-in combo modules of types A, B, E and E/D for analog, RTD, flow pulse and densitometer inputs, plus HART modules where smart transmitters are used.
• Pulse fidelity checking on the E module, so complete failure of one channel does not affect totalizing and simultaneous noise pulses are rejected.
• Daily, batch and prove historical reports, a detailed daily report for gas, alarm reports and separate system and measurement audit trails.
• One administrator and sixteen users with separate permissions, eight port passwords, software sealing and SSL encryption on Ethernet connections.
• Configurable but not programmable firmware, which protects WELMEC-approved code and the certifications that depend on it.
• Universal power input of 90 to 264 VAC or 22 to 26 VDC with 24 VDC transducer power available from the back panel.

Industrial Applications

In Oman the OMNI 4000 fits the many smaller custody and allocation points that sit around the large export systems: crude and condensate LACT skids at production stations, product loading bays at depots and terminals, LPG and NGL transfers at gas processing plants, and gas sales points feeding power and desalination plants. Its compact depth suits analyzer shelters and metering cabinets where panel space is limited, while the same firmware and configuration files as the OMNI 7000 keep training and spares simple for operators who run both models.

Seven Star LLC supplies this flow computer for new metering packages and for the replacement of older flow computers in Muscat, Sohar, Duqm and Salalah, as well as on projects in the wider GCC. Customers comparing models often look at the OMNI 7000 Flow Computer with Display for high-run-count stations and at the OMNI 6000 Flow Computer with Operator Display on existing sites, and the OMNI 4000/7000 Series page gives an overview of the platform.

Technical Specifications

The following data for the OMNI 4000 is taken from the OMNI 4000/7000 Installation Guide attached on this page.

How to Order

For a quotation on the OMNI 4000, send Seven Star LLC your metering philosophy or I/O list: number of runs, meter types, transmitters, prover arrangement and communication needs. Our Muscat team will propose the module set, share the attached installation guide and support delivery to sites in Oman and across the GCC.