參數(shù)表節(jié)選：的技術參數(shù) LVL-A7-BG4B-E5PU-CG-EMS
| General specifications | ||
|---|---|---|
| Measuring method | The tuning fork is brought to its resonance frequency by means of a piezoelectric drive. If the tuning fork is covered by liquid, this frequency changes. The electronics monitor the resonance frequency and indicate whether the tuning fork is freely vibrating or is covered by liquid. | |
| Construction type | device with short tube | |
| Operating mode | MAX = maximum safety: The device keeps the electronic switch closed as long as the liquid level is below the fork. example application: overspill protection MIN = minimum safety: The device keeps the electronic switch closed as long as the fork is immersed in liquid. example application: dry running protection of pumps The electronic switch opens if the limit is reached, if a fault occurs or in the event of a power fails (quiescent current principle) | |
| Supply | ||
| Connection | This device may be used with any sequential circuit, as long as the circuit can support the electrical circuit values of the switching elements. | |
| Rated voltage | 10 ... 35 V DC | |
| Fusing | external 500 mA slow | |
| Current consumption | < 15 mA | |
| Power consumption | 975 mW | |
| Residual ripple | 5 V ss at 0 ... 400 Hz | |
| Input | ||
| Measured variable | density | |
| Measurement range | min. 0.7 g/cm3 | |
| Output | ||
| Output type | switch output | |
| Switching current | max. 250 mA | |
| Directive conformity | ||
| Electromagnetic compatibility | ||
| Directive 2014/30/EU | EN 61326-1:2006 , EN 61326-2-3:2006 | |
| Directive 2004/108/EC | EN 61326-1:2006 , EN 61326-2-3:2006 | |
| Conformity | ||
| Electromagnetic compatibility | NE 21 | |
| Degree of protection | IEC 60529 | |
| Shock resistance | EN 60068-2-27 | |
| Vibration resistance | EN 60068-2-64 | |
| Climate class | DIN EN 60068-2-38/IEC 68-2-38 | |
| Measurement accuracy | ||
| Reference operating conditions | - ambient temperature: 25 °C (+77 °F) - process pressure: 1 bar (14.5 psi) - fluid: water (density: approx. 1 g/cm3, viscosity: 1 mm2/s) - medium temperature: 25 °C (+77 °F) - density setting: > 0.7 g/cm3 - switching time delay: standard (0,5 s, 1 s) | |
| Measured value resolution | < 0.5 mm | |
| Measuring frequency | approx. 1100 Hz in air | |
| Switching point | 13 mm ± 1 mm | |
| Non-repeatability | ± 1 mm acc. to DIN 61298-2 | |
| Hysteresis | max. 3 mm | |
| Influence of ambient temperature | negligible | |
| Influence of medium temperature | -25 μm/°C | |
| Influence of medium pressure | -20 μm/bar | |
| Switching time | - 0.5 s when tuning fork is covered - 1.0 s when tuning fork is uncovered | |
| Switch-on delay | max. 3 s | |
| Operating conditions | ||
| Installation conditions | ||
| Installation position | see technical information (TI) | |
| Ambient conditions | ||
| Ambient temperature | -40 ... 70 °C (-40 ... 158 °F) | |
| Storage temperature | -40 ... 85 °C (-40 ... 185 °F) | |
| Shock resistance | a = 300 m/s2 = 30 g, 3 planes x 2 directions x 3 shocks x 18 ms, as per test Ea | |
| Vibration resistance | a(RMS) = 50 m/s2, ASD = 1.25 (m/s2)2/Hz, f = 5 to 2000 Hz, t = 3 x 2 h | |
