Starting at $3,945.00
  • Usually ships in 2-3 weeks



  • Recommended for clean liquids with less than 2% solids or gas bubbles
  • Flow range: 0.65 to 40 ft/sec (0.2 to 12 m/sec)
  • Accuracy: ±2% of reading in most applications, ±0.5% repeatability
  • Pipe size:
    • ‘A’ Transducers - 0.51" to 4.5" Outside Diameter (13 mm to 115 mm)
    • ‘B’ Transducers - 2” to 39.37” Outside Diameter (50 mm to 1000 mm)
  • Pipe wall thickness: 0.039 - 2.95”
  • Output: 0/4-20mA, 5V pulse
  • Works with any sonic conducting material including carbon steel, stainless steel, PVC,
  • PVDF, fiberglass, galvanized steel, mild steel, glass, copper, brass and pipes
  • with bonded liners including epoxy, rubber and Teflon
  • Portable, ABS IP54 rated enclosure
  • Built-in 16-key programming with user-friendly calibration menu
  • Internal battery and/or AC powered

What's in the Box

  • Pair of Type 'A' transducers for 0.5" to 4.5" diameter pipes
  • Pair of 6 ft. coaxial transducer cables with connectors
  • Transducer mounting kit with guiderail and stainless hardware
  • Ultrasonic acoustic couplant
  • Carrying case
  • External battery charger 100-240VAC 50/60Hz
  • Installation and operation manual


The Greyline Instruments PT400 ultrasonic flow meter is a portable unit that relies on transit time technology to measure the flow of clean fluids like water, glycol, oil and most chemicals. The PT400 is recommended for clean liquids with less than 2% solids or gas bubbles. Since the transducers of the P400 are mounted on the outside of the pipe, there is no obstruction or pressure drop and they can be mounted without shutting down flow.

Calibrating the PT400 is easy with the onscreen menu system. Enter the pipe diameter, wall thickness and pipe material, and the unit calculates the optimum mounting method and separation distance for the sensors. The ease with which the PT400 is set up makes it ideal where a permanent flowmeter is not required or to temporarily replace installed flow transmitters. Use it for spot checks or for extended operation as a 4-20mA flow transmitter

The Greyline PT400 is available with one of two transducer pairs: 'A' transducers are for pipes with an outside diameter of between 0.51" and 4.5" while 'B' transducers are for pipes between 2" and 39.37". The ultrasonic signal travels through all common metal and plastic pipe materials. Flow rate and totalizer are displayed continuously along with battery status, signal strength. Press one key to instantly change the units of flow measurement (e.g. from gallons to liters). Real time flow can be displayed in large numeric values or as a graph.