Four-Path Ultrasonic Flow Meter (4-Channel)

Four transducer pairs sit on four offset planes of the pipe cross-section. Each pair fires acoustic pulses upstream and downstream and times the transit difference, giving a path-average velocity. The firmware applies Gaussian-quadrature path weights to combine the four path velocities into an estimate of the cross-section mean velocity. Four planes sample more of the profile than 1 or 2 paths, so asymmetry from upstream elbows, reducers, or partial valves averages out across the four paths.

Same headline accuracy (±0.5 % at 0.5-5 m/s) but two physical advantages. First, sampling density. Four paths cover roughly 80 % of the cross-section profile via Gaussian quadrature, where 2 paths cover about 60 %. On very-large-bore lines (DN1000+) where the profile is harder to under-sample, the gap matters. Second, redundancy. Four independent path readings provide a self-consistency check the firmware can flag if one drifts. Useful for fiscal sub-measurement audit trails. Cost is roughly 70-80 % above the 2-path meter.

Double elbow out-of-plane, half-open valve immediately upstream, sudden pipe expansion; these defeat 1- and 2-path meters because profile asymmetry exceeds what a 2-path average can correct. Four paths on different planes bracket the asymmetric profile symmetrically, and the path-weighted average holds where meters with fewer paths cannot. Severe disturbance still degrades accuracy below ±0.5 %, but the degradation is much smaller than what a 2-path or single-path meter shows.

Yes, with the optional PT100 supply + return pair. The transmitter accepts two PT100 inputs and runs the BTU calorimetry firmware that solves E = ∫(ṃ × Cp × ΔT) dt. Output is selectable between kWh, MJ, and BTU on the display and on the 4-20 mA energy-rate channel. Suits district-heat substation primary, large-bore HVAC, and fiscal-billing applications where the 4-path self-consistency check provides audit-trail redundancy. Specify with-BTU at order.

The package ships with the flow body (C8) or transducer set (W8), the transmitter, signal cable (length factory-set per order), the calibration record (serial number, tested flow range), and a pre-configured Modbus register map and slave address. Optional PT100 BTU pair adds two temperature sensors plus coupling paste and stainless straps. Lead time is 5 to 7 business days from the factory. Notified-body custody-transfer certificates are buyer-arranged with the local metrology authority.