|WORLD METEOROLOGICAL ORGANIZATION||
|Explanation of the criteria for classification and numbering of components||
|Explanation of the dates on the component's description|
SENSA ELECTROMAGNETIC OPEN CHANNEL FLOW METERS
1. Purpose and objectives
water velocities in rivers, streams, sewers and other
open channels. Exceptionally high sensitivity down to 1mm/sec
permits measurement in very shallow and sluggish flows, and is
invaluable for hydraulic modelling.
The instruments measure the velocity of water or other aqueous fluid flowing over a sensing probe. The measurement method uses the Faraday Principle of Electromagnetic Induction, where a conductor moving in a magnetic field has induced in it a voltage proportional to the speed of movement. In this case the water is the moving conductor, and the induced voltage is sensed by two electrodes on the probe.
The probes have no moving parts, and the initial calibration remains valid for life. They are also unaffected by debris and suspended solids in the flow, making them ideal for sewer flow measurement and other difficult applications.
Several versions of the instrument are available, all using the same probes and measuring principles. Probe cables may be up to 60m as standard.
SENSA- RC2 is a battery powered portable system for measurement of flow velocity over the range 0 to 4 metres/sec, with resolution down to 1mm/sec. LCD display of instantaneous or averaged readings, with RS232 output as standard.
SENSA-RC3 is a
battery-operated system for portable or
semi-permanent applications. Fully bi-directional measurement
from -8.00 to +8.00 m/sec, with 1mm/sec resolution. Selectable
averaging and built-in data logging facilities with programmable
sampling and time/date recording. LCD display
SENSA-RMX is a multi-channel version of the Sensa-RC3 that can operate with up to 6 velocity probes simultaneously. All the measurement and data-logging functions are available for the selected probes.
All instruments can display instantaneous velocity, or the velocity averaged over the range 2 to 60 seconds. Longer averaging periods may be supplied on request. Operating temperature is - 5 to + 50 °C. The control boxes are rated to IP67, and are designed to float if dropped in the river.
Wading Rod Kit allows measurement at specified depths,
in accordance with standard gauging procedures.
along the axis of a submerged probe.
in metres/second of the velocity, displayed on the internal LCD
display and also transmitted as an ASCII string from the
RS232 output. Together with depth information provided by the
Wading Rods, manual or computer calculations can be performed to
calculate stream flow.
5. Operational requirements and restrictions
The instruments are designed for use by a single unskilled operator. Operation is extremely easy, and little training is required for basic measurements. Higher skill levels and training are suggested for gauging larger rivers.
All the instruments are battery powered, using commonly available batteries. Rechargeable batteries are available as an option.
specifications of the instruments are available.
7. Operational experience
instruments are used by Water Authorities, Universities
and Environmental Agencies worldwide. Over 1000 have been
supplied since 1990.
8. Originator and technical support
Services Ltd. England.
From Aqua Data
10. Conditions of use
Instruments are for sale direct from manufacturer or from agents.
|(First entered: 1 DEC 00||
Last updated: 1 DEC 00)