Float & Tape Tank Level Indicator

As float on the liquid surface, displaces certain volume of liquid resulting therefore in apparent loss of weight. The apparent weight of the float is balanced by the pointer weight attached to the measuring wire. Change in in level of liquid, results in the float being raised or lowered by the balancing action of the weight and thus follows the liquid level. The mechanical chain/belt wheel moves accordingly indicating the level for reliable and accurate monitoring. This system can connect with a transmitter which can have an 4-20 mA output, or Hart and RS 485/Modbus

Working Principle and Structure

LiquiLevel LLFT series Float and steel strip level indicator is designed subject to the principle of force balance. Its principle and structure and working status are shown below. The Float (1) floats on the liquid to be monitored and measured is under actions from gravity (W) Buoyancy (F) and constant pulling force (P) of balancing spring (5) When the vector sum of three forces equals zero, the float is under a balanced status. When the change of liquid level occurs, the float will produce a displacement accordingly, which results in transmitting the steel strip (2) to drive the chain/belt wheel (4) through the high precission punched hole connected to the float to convert the change of liquid level into angular displacement signal, then the signal is output via the drive pin (7) for the coupling with the transmitter to show liquid level value through the counter (3) sharing the same axis with the chain/belt wheel. The instrument is mainly made up of liquid-checking unit (float), high precission displacement transmission system. (transmission steel-strip and chain wheel) constant force unit (Component of spring) display (counter), support of guide pipe conduit, 90 degree elbows, steel wire strainer, bottom anchor base etc. The drive pin on the gauge is used to connect to the required transmitter.

Technical Parameters (mechanical)

• Normal Working conditions;.- (D2 grade ground) Temperature: -40°- 85° (°C) Relative humidity (%) 5 - 100 including moist and direct wet) Atmospheric pressure (kPa) 86 - 108.
• Measuring Range: (metres) 0-6 mtr, 0-12 mtr, 0-18 mtr and 0-20 mtr.
• Measuring tolerance: (mm) +/- 4.5 
• Sensitivity: (mm) 1.5
• Working pressure. (MPa) 0-40.
• Medium temperature: (°C) -40 - 200.
• Display method: Five digit capacity, i.e: Decameter, meter, decimeter, cetntimeter, millimetre, to be displayed by three digit counter and scale.

Transmitter part for output

• Measuring range: 0 - 2 metre.
• Accuracy: +/- 5%
• Error: +/- 1 mm
• Output: 4-20 mA/ 4-20mA ? HART/RS485/Modbus.
• Remote distance: upto 1000 metres.
• Explosion proof: Exd11BT4.
• Protection: IP 65.

For more information please contact our technical or sales team today.