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LST400 Ultrasonic Level Transmitter
Brand: ABB GroupThe LST400 is an Ultrasonic Level Transmitter capable of measuring liquid level or solid applications up to 50 ft. / 15 meters or flow rates in all types of open channel flow applications.
The transmitter has a single 4-20 mADC analog output with HART 7 and five (5) relay outputs. A transducer is fitted to the top of a silo or tank, facing down towards the material being measured.
The transmitter’s microprocessor simultaneously fires an electronic pulse to the transducer and starts a timer. The transducer converts this electronic pulse to an acoustic pulse, which is directed toward the surface of the material being measured.
When the acoustic pulse contacts the surface of the material, energy is reflected back to the transducer, which converts this reflected energy back to an electronic pulse. This pulse is sent back to the microprocessor, which stops the timer and determines the “time of flight” of the signal.
By combining the speed of sound through air and the “time of flight” of the pulse, the microprocessor accurately determines the level of the product. Powerful software removes false echoes from the signal and electronic filters remove ambient noise.
Features- Range to 50 ft. / 15 m
- Isolated 4-20 mA Output with HART 7
- Graphic LCD Display
- Integrated Analytical Software
- 5 Configurable Relays / 8 Amp
- Configurable as Open Channel Flow Meter
- Pump Cycling and Pump Monitoring
- Remote Totalizer Count Outputs
- Automatic Variable Gain & Power for Difficult Applications
- Options
- Transducers for Liquids & Solids
- Cable length of 10 m, 20 m, 30 m, 40 m or 50 m
- Aiming Kit
Specifications
Brand
Communication
- HART
Output Signal
- 4-20 mA
Display
- LCD
Range
- 1.5 to 30 m (S30)
- 0.5 to 15 m (S15, C15, F15)
Accuracy
- 0.25 % Full Span with Temperature Compensation or 3 mm (0.11 in), whichever is greater
Repeatability
- 0.15 % Full Span
Temperature Compensation
- NTC 10 k Ω Thermistor: -40° to 80° C (-40° to 176° F)
Measurement Modes
- Open Channel Flow with Preconfigured Flow Curves for Most Common Channels
- Distance
- Level
- Linearized Level (21-Point Linearizer)
Rate of Cchange
- 0.01 to 20 m/minute
- 0.03 to 65 ft/minute
Resolution
- 0.1 % at 10 mA, 0.05 % at 20 mA
Environmental Protection
- IP65 / NEMA 4X
Power Supply
- 20-30 Vdc, 4 VA
- 110 VacC or 240 Vac ± 15 %, 50/60 Hz, 5 VA
Process Connection
- 1” NPT
Operating Temperature
- -20° to 65° C (-4° to 149° F)
Storage Temperature
- -25° to 75° C (-13° to 167° F)
Certifications & Approvals
- EMC
- CE
- Various Liquids Including Water Storage Tanks
- Moderate Range Solids Such as Loading & Bagging Hoppers
- Mineral Oil
- Open Channel Flow Measurement in the following configurations
- V-Notch
- Flumes
- Weirs
