Swoffer Instruments Inc.

Swoffer Instruments Inc.

Swoffer Instruments Inc.

Flow Instrumentation. Swoffer Instruments, Inc has been manufacturing water velocity related instruments since 1959. Beginning then with the first electronically operated sailboat speedometer and continuing to expand into open channel velocity measurement. The Model 2100 instrument was introduced in 1980 and has been one of the most reliable water current measuring instruments in the US.

Company details

1112 S. 344th St, Suite 302 , Federal Way , WA 98003 USA
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Business Type:
Industry Type:
Water Monitoring and Testing
Market Focus:
Internationally (various countries)
Year Founded:

The basic principle of the Swoffer fiber-optic sensor is simple and unique: Multiple bundles of fiber-optics, assembled into a propeller driven rotor, gate a beam of infrared light from a photo diode to a photo-sensitive transistor producing electronic pulses. These pulses, generated by the propeller rotor over a precisely measured amount of time, are directly proportional to water velocity.

The electronic half of the sensor is the latest opto-electronics and is epoxy encapsulated in a ½' (12.7mm) diameter acetal resin housing for protection from chemicals and the elements. It can be purchased separately and attached to and used with many in-water devices in addition to those offered by Swoffer. The sensor uses a two-wire signal system requiring only 3 volts for operation and can generate an output signal through over 1000 feet of cable.

The rotating portion of the sensor consists of a very low friction fiber-optics rotor rotating around a polished & hardened stainless steel shaft, all driven by a glass-reinforced nylon propeller. All rotor parts are easily replaceable in the field and spares are provided with every new instrument.