Model 612 Seawater Flow Monitor

buy now
Buy Factory Direct: $299 (unit only)

Product Summary

No Moving Parts! Rugged and Reliable! Will not foul or corrode

The Model 612 Seawater Flow Monitor protects main and auxiliary engines by warning of a partial or complete loss of seawater cooling capacity. A sensor probe, mounted in a tee in the intake line, senses water velocity without moving parts. This data is interpreted and displayed in bar graph form by an electronic module in the engine room.

Optionally, this same information can be displayed remotely in the wheelhouse, bridge or control room up to 250 feet away.

The 10-segment remote bar graph display is ultra blue in color and automatically adjusts its brightness for optimum viewing in all lighting conditions. Remote displays are available in single or dual versions for easy comparison of flow rates. Special stainless steel tees accommodate hoses of 1 to 3 inches inside diameter. Adjustments are provided to optimize the response of the flow monitor for large variable-speed main engines as well as small constant-speed auxiliary engines.

Event, alarm and analog outputs may be used for an optional annunciator and/or a data collection system. A fault in the sensor or its cable is automatically detected and causes the display to flash.

Model 612 Sensor and installation options


Note: The 612 is designed for use with a SF5200 316 medical grade stainless steel differential flow sensor(right) made by IFM in Germany or its equivalent. The IFM unit is not cheap but it's very good. There are lower cost differential resistance sensors with adaptors and harnesses already included that will work – Google lists quite a few. See specs for sensor input requirements. Our tech support will be glad to assist if you want to use a different sensor or have an application not requiring a tee.

You may be able to purchase an IFM equivalent or an original at a better price, plus have a different application or installation not requiring a tee or adaptors, which is why it we list each as sold separately. If required, a good assortment of Tees are available in sizes to fit pipes from I" ID to 3" ID with varying prices – call or email for sizes & price. A stainless steel tee to fit 2 ¼" ID pipe is listed for reference.

Model 612 Sensor and Accessories

  • 57-6120-11 IFM sensor $224.75
  • 57-6120-14 16' (5m) sensor interconnecting cable $24
  • 57-6120-01 2 ¼" pipe ID Stainless tee for IFM sensor $42.90 (call for other sizes)
  • 57-6120-10 threaded tee adaptor for IFM sensor $24

The complete package price with the sensor and components is $599 with a 2 ¼ inch tee. Specify the operating voltage and tee size when ordering the package.

Model 612 Accessories:

  • 57-A612-50 single channel remote display $140 (2ch available - call for details)
  • Model 1550 Engine Cost Saver – monitors and records seawater flow and the rest of the engine's performance $585
sea water flow monitor


  • Suitable for main or auxiliary engines
  • 12v or 24v operation
  • For hoses from 1 to 3 inch I.D.
  • Wetted parts are 304 stainless steel
  • Removable anti-fouling sensor probe
  • Built-in bar graph display
  • Remote single (5 1/4" x 2 1/2") or dual (5 1/4" x 3 1/2") bar graph displays require only 1 1/2" mounting depth
  • Sensor/harness assembly 16' / 5 meters
  • Auto-dimming for all lighting conditions
  • Programmable alarm and event outputs
  • Analog output for data collection
  • Self testing with failure warning
  • Easy installation and adjustment

Manuals and Downloads

Flight Systems' manufactured products are made in the USA