Open Stream Current Velocity Meter

• Efficient propeller-driven Photo-Fiber-Optic sensor coupled with precision quartz crystal controlled electronics provide accurate repeatable data in all flow conditions.
• The Model 2100 Indicator reads data in feet and meters per second. A toggle switch in the battery compartment changes from one to the other.
• Powered by a single 9 volt transistor battery and there is a spare in the battery compartment too.
• Three user selectable velocity averaging times in each mode. From 5 to 90 seconds in feet per second and from 1.5 to 30 seconds in meters mode.
• Sensor components (propeller, rotor, and rotor shaft) easily and inexpensively replaceable. Carry spares into remote locations and you'll never have to return early because of a bent bucketwheel, lost sensor magnet or bent shaft.
• Wide choice of sensor carriers or "wands" to accommodate virtually any open stream velocity measuring requirement.
• Lightweight, portable system is easy to work with all day in the field. Indicator weighs a little over a pound and a half.
• A simple and accurate method of user-accomplished calibration is provided with the Model 2100. No other current meter provides the user a method of checking and changing calibrations while in the field. Calibration settings for the feet and meters selection are easily checked and changed any time.

THE SWOFFER OPTICAL-ELECTRONIC SENSOR

The basic principle of the Swoffer 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 Model 2100 propeller rotor requires very little energy to activate, works in nearly all water conditions and produces consistent, strong output pulses even at low velocities. The calibration curve for the rotors is linear and consistent in all naturally occurring open channel velocities. Propellers used with the Model 2100 are specifically designed for water so they do not require a shroud to protect them from the effects of turbulence. Because no shroud is used the propellers are easily able to shed the debris normally found in sewers and natural streams.

The electronic half of the sensor contains state of the art opto-electronics and is epoxy encapsulated in a ½” (12.7mm) diameter acetal resin housing for protection from chemicals and the elements. The sensor uses a two-wire signal system requiring as little as 3 volts DC for operation and generates an output signal through as much as 1000 feet of cable. Because the sensor consumes such a small amount of power, the field life of the Model 2100 battery (a standard 9 volt size) is long. The sensor emits four pulses per revolution so the resolution of the instrument is much higher than other sensors on the market. It is extremely accurate especially at very low velocities. It is also the most rugged and is extremely sturdy and reliable.

The standard version of the propeller rotor assembly (2100-A21) uses a very low friction fiberoptic rotor, a polished and hardened stainless steel shaft, and a 2” glass-filled nylon propeller. All rotor parts are easily replaceable in the field and a spare rotor assembly is provided with every new instrument.

SPECIFICATIONS

CAT. NO.	DESCRIPTION
2100-TSR-Kit	Current Velocity meter adapts to your USGS Top-Set wading rod
2100-STDX	Current Velocity meter and 2.5 ft. - 9.5 ft. Telescoping Wand
2100-LX	Current Velocity meter and 4.5 ft. - 19.5 ft. Telescoping Wand
2100-12	Current Velocity meter and 2.7 ft. Top Set wading Rod
2100-13	Current Velocity meter and 3.7 ft. Top Set wading Rod
2100-14	Current Velocity meter and 4.7 ft. Top Set wading Rod
2100-C80	Current Velocity meter and 80cm Top Set wading Rod
2100-C140	Current Velocity meter and 140cm Top Set wading Rod
2100-1514	Current Velocity meter and 12 ft. Combination Wading Rod
2100-1518	Current Velocity meter and 4 meter Combination Wading Rod
Carrying Cases
P-1450	Pelican 1450® waterproof polypropylene carrying case
P-1200	Pelican 1200® waterproof polypropylene carrying case
Digital Indicator only (Available separately as replacements, repairs or upgrades)
2100-Indicator	Current Velocity Indicator with neck strap
Sensor Replacement Parts
2100-A21	Complete Rotor Assembly; 2" prop, optics rotor, shaft & thrust bearing nut
2100-A22	Sensor w/o Rotor Assembly, up to 25' cable w/ connector
2100-A23	Thrust Bearing Nut
2100-PROP	Glass Filled Nylon Replacement Prop 2" Dia.(standard)
2100-PROP3	Glass Filled Nylon Replacement Prop 3" Dia.
2100-PROP1	Glass Filled Nylon Replacement Prop 1 3/8" Dia.
2100-A25	Replacement retainer snap ring for rotor shaft 2100-A26 Stainless Steel Rotor Shaft (also includes a retainer snap ring)
2100-A27	Fiber Optics Rotor
6-32 Set	Screw Sensor and Rotor retaining screw
1ž2" Cap Plug	1ž2" Cap Plug (Protects sensor when not in use)
Extension Cable	Sensor Extension Cable, any length, twist lock connector at both ends