Explanation of the criteria for classification and numbering of components     C71.3.14
(JUN 00)
Explanation of the dates on the component's description



1.   Purpose and objectives

     A water level sensor developed for use in observation stations with telemeters and drainage pump stations. It can be connected directly with wireless equipment and data processors. It further allows simultaneous measurement and digital recording/printing.

2.   Description

     Reed switches at 1 cm intervals are turned on and off by a magnet in a float. This provides a series of electrical signals for the output. This 1 cm accuracy can be guaranteed irrespective of the total measurement range.

     This water level meter can function fully automatically as a system for water level measurement and recording.

3.   Input


4.   Output

     Output signal is water level BCD signals delivered to telemeter equipment etc. Digital recording and printing allows recording and printing at a given time step. In case a pre-set alarm water level is exceeded, data is recorded at a shorter time interval, and an asterisk is printed in front of the corresponding values.

5.   Operational requirements and restrictions

     Except for civil engineering works necessary for the construction of the facilities to install this unit, the number of professional level personnel for its installation, operation and maintenance is of at least 

     In case of recording the data measured at the site, it is necessary to replace the paper tape periodically (about every 6 months: paper tape is required for 6 months use with max. one hour printing per day). When battery is used as the only power source, it is also necessary to replace it for a charged battery periodically.

     Ambient temperature is -10 to +50 C for the sensor, but a heater should be applied to prevent freezing. It is -10 to +40 C for the coder, with humidity below 90 %, though no condensing is allowed.

     There are 6 different ranges (per water level meter) of water level measurable: 0 to 1 m, 0 to 1.5 m, 0 to 2.0 m, 0 to 2.5 m, 0 to 3.0 m and 0 to 3.5 m. Subject to measurement range, combination use is done. 

6.   Form of presentation

     A catalogue and specifications of the instrument and home page are available at

7.   Operational experience

     Japanese users in more than 2500 places may answer for the reliability of this water level meter, which has been in use since 1967. Several units have been exported to Philippines and Indonesia.

8.   Originator and technical support

     Takuwa Corporation.

9.   Availability

     From the HOMS National Reference Centre for Japan.

10.  Conditions on use

     The hardware is for sale.


(First entered: 1 FEB 93

Last updated: 21 APR 00)