FDT-25-Flow-Meter

Supported Applications

The Omega FDT-25 Series is a handheld ultrasonic flowmeter designed for non-contact, clamp-on measurement of liquid flow velocity in closed conduits. The system measures flow by transmitting and receiving ultrasonic pulses between two transducers mounted on the pipe exterior, calculating velocity based on the difference in transit time (Tup - Tdown). It supports multiple mounting methods: V, W, Z, and N.

Documented compatible media include most liquids such as clean water, sea water, waste water, chemical liquids, oil, crude oil, alcohol, beer, and more. The instrument is designed to operate with pipes constructed of all metals, most plastics, and fiberglass (liner allowed).

Operating Conditions & Performance

The FDT-25 operates within an ambient temperature range of -20 to 60°C (-8 to 140°F) and supports a humidity rating up to 85% RH. The device features IP65 enclosure protection.

• Measurement Range: Pipe sizes from DN15~DN6000mm (with optional transducers); Velocity range of ±32 m/s.
• Process Temperature Limits: 0 to 90°C (32 to 194°F) for Standard Transducers; 0 to 160°C (32 to 320°F) for High Temp Transducers.
• Accuracy: ±1% of reading at rates >0.2m/s (0.6 ft/s).
• Repeatability: 0.2%.
• Resolution: 100 Pico-second resolution of time measurement.

The built-in rechargeable NiMH battery can work continuously for more than 12 hours without recharge (spec sheet notes over 10 hrs). The device includes a user-configurable response time from 0 to 999 seconds and features advanced signal processing for operation near power frequency transverters.

Configuration Options

The series supports various configurations through interchangeable clamp-on transducers, cables, gels, and accessories. The standard kit includes the flow meter unit, a Small Standard Transducer (STD-HS), transducer cables, chain, clamp, ruler, RS232 cable (1 meter), universal AC power adapter/battery charger, and acoustic gel for standard transducers.

Available transducer options cover specific pipe size ranges:

• Standard Transducers (0 to 90°C):
• STD-HS: Small, Pipe Size DN15~DN100 (3/4" to 4")
• STD-HM: Medium, Pipe Size DN50~DN700 (2" to 28")
• STD-HL: Large, Pipe Size DN300~DN6000 (12" to 240")
• High Temperature Transducers (0 to 160°C):
• HT-HS: Small, Pipe Size DN15~DN100 (3/4" to 4")
• HT-HM: Medium, Pipe Size DN50~DN700 (2" to 28")
• HT-HL: Large, Pipe Size DN300~DN6000 (12" to 240")

The unit features a built-in data logger that stores over 2000 lines of data and includes four flow totalizers with a 7-digit display for net, positive, and negative flow. Output capabilities include RS232C serial interface (baud rate from 75 to 115,200 bps), Frequency Output, Totalizer Pulse Output, and OCT output.

Key Product Differences

The primary variation within the FDT-25 series is defined by transducer selection based on pipe diameter and fluid temperature requirements. Standard Transducers (STD) are rated for 0 to 90°C, while High Temperature Transducers (HT) extend this capability to 160°C.

Transducer sizes are categorized as Small (S), Medium (M), or Large (L), each covering distinct pipe diameter ranges from DN15 up to DN6000. The device housing is ABS plastic with an aluminum alloy protective carrying case, and the unit weighs 514 g (1.2 lb). Additional accessories include acoustic gel specific to standard (STDGEL) or high-temperature (HTGEL) transducers and replacement transducer cables (TCH).