Description
The GE Panametrics DigitalFlow XMT8681 (commonly designated as the XMT868i) is an explosion-proof, microprocessor-based ultrasonic flow transmitter engineered for continuous flow measurement of acoustically conductive liquids. Originally manufactured under the Panametrics brand and subsequently produced through GE Sensing and Baker Hughes, this transmitter uses patented Correlation Transit-Time digital signal processing. It handles clean liquids as well as fluids containing entrained gases or suspended solids across chemical, petrochemical, oil and gas, and water treatment utilities.
Product Specifications
| Parameter | Value |
| Manufacturer | GE Panametrics / Baker Hughes |
| Product Series | DigitalFlow XMT868i (XMT8681 variant) |
| Measurement Technique | Patented Correlation Transit-Time ultrasonic method |
| Fluid Types | Clean liquids, or liquids with up to 10% entrained solids or gas bubbles |
| Pipe Size Range | Clamp-on: 0.5 to 300 in (12.7 mm to 7.6 m); Wetted: 1 to 200 in (25.4 mm to 5 m) |
| Flow Accuracy (Velocity) | \pm 0.5\% of reading with process calibration; \pm 1\% to 2\% typical for clamp-on configurations |
| Repeatability | \pm 0.1\% to \pm 0.3\% of reading |
| Velocity Range | -40 to +40 ft/s (-12.2 to +12.2 m/s), bidirectional |
| Enclosure Rating | Epoxy-coated aluminum Type 4X / IP66; Explosion-proof / Flameproof Class I, Division 1 (Groups B, C, D) |
| Display & Interface | Optional 2-line x 16-character backlit LCD; built-in infrared 6-button glass-touch keypad |
| Power Supply | Standard: 90 to 260 V AC; Optional: 12 to 28 V DC (\pm 5\%) |
| Operating Temperature | -40 to +60 °C (–40 to +140 °F) electronics enclosure limits |
| Standard Outputs | Two isolated 0/4 to 20 mA analog outputs, RS-232 serial communication interface |
| Optional Communication | HART, Modbus RTU, Foundation Fieldbus, RTD inputs for thermal energy/temperature compensation |
Commercial & Logistics Information
- Condition: New Original Factory Sealed / Factory Surplus / Fully Tested Refurbished Options
- Availability: Stock levels fluctuate based on specific hardware configurations; standard units typically ready for quick dispatch
- Standard Lead Time: 1 to 3 business days for stock items; specialized transducer bundles or custom firmware options may require extended delivery timelines
- Warranty: 1-year standard vendor or manufacturer replacement warranty (verify terms with specific procurement agreements)
- Pricing Note: Listed price is indicative and subject to change based on market supply and configuration options (such as single-path vs. dual-channel firmware). Contact our engineering sales desk for a formal quotation.
Technical Application & Integration Notes
The XMT8681 enclosure features an infrared glass-touch keypad system, allowing instrument technicians to navigate menus, adjust parameters, and run diagnostics without opening the housing cover in hazardous environments. For advanced configuration and data logging, connect via the onboard RS-232 link to Panametrics PanaView PC software.
When deploying clamp-on transducers, ensure proper pipe surface preparation—including the complete removal of rust, scale, and loose paint—and apply the correct couplant compound to maintain ultrasonic signal strength above operational thresholds. For precise mass flow or energy measurement applications, pair the transmitter with dual-path wetted transducers and external RTD temperature inputs.
Frequently Asked Questions
Q: What is the difference between the XMT8681 designation and the standard XMT868i naming?
A: “XMT8681” is frequently used interchangeably or as a variant code in customer requisitions and legacy ERP systems for the standard Panametrics XMT868i explosion-proof ultrasonic transmitter line. Always verify the specific option card code suffix on the nameplate.
Q: Can this transmitter be used in dual-pipe applications?
A: Yes, with the optional dual-channel software configuration, a single XMT8681 unit can monitor two independent pipes simultaneously, or serve as a dual-path measurement point on a single pipe to minimize upstream flow disturbance errors.
Q: How do you perform parameter changes safely in a hazardous area?
A: The transmitter utilizes an internal infrared optical sensor board behind the glass cover window, enabling touch-free menu navigation via the six-button layout without breaking the flameproof seal.
