Description
The VBW-108 is an 8-channel Interface Unit for Vibrating Wire Sensors. Each channel consists of 2 inputs for the sensor coil and 2 inputs for associated thermistor temperature sensors. The unit is compatible with sensors from most of the major manufacturers.
The VBW-108/A variant is a VW Interface Unit with Analog Outputs : Each VW input has a corresponding Analog Output which provides a 0-2.5Vdc value scaled to the input. This output can then be connected to a Data Acquisition/Data logging system. This may be easier to implement if other devices are planned to be used with the same host computer or spare channel capacity is available on an existing system. It also makes it simple to connect to our DataWeb Data Logger.
Features
- 8 x 4 Wire Vibrating Wire Sensor Inputs (4 wire)
- 8 x Analog Output - Frequency Sensors 0-2.5 V DC
- 8 x Analog Output - Temperature Sensors 0-2.5 V DC
- Resolves the VW signal to less than 0.001 Hz (industry standard 0.1 Hz)
- Gas Discharge Tube Sensor Protection
- Real-time Frequency Display - 5 digit
- Audible Output
- Auto Resonance VW Excitation
- RS-485 Network Support
- Automatic VW sensor configuration
- Digital communications to remove noise sources and errors.
- Simplified configuration and data logger support
- Output - Frequency - Hz, Digits, Temp Deg C
- Steinhart-Hart Thermistor Linearisation
- Terminal Port for Sensor Set-up
Specifications
Description
- Frequency Display: 5 Segment display Resolution 0.1 Hz
- Vibrating Wire Inputs: 8 x 4 Wire Inputs (User-Selectable)
- 8 Analogue Inputs: 0 - 2.5Vdc, 3.3K / 10 K Thermistor
- VW sensor coil resistance to 2 K Ohm (standard):- other ranges on request
- Frequency range: 400 - 6 KHz (standard) Other ranges on request
- Frequency Resolution/Accuracy: 32 bit resolution, 0.001 Hz
- Distance of VW sensor to interface: 0 .. 10 Km depending on cabling
- VW sensor units: Temperature sensor Hz, Digits ( Hz2 ), SI Units y = A + B.F + C.F2 + D.F3 Deg C, mV
- Temperature range: -50 to 70 Deg C
- Temperature resolution: 0.1 'C +/- 0.2 Deg
- Temperature accuracy: ± 0.2 'C / 0.2 'F RS-485
- Thermistor 10 K Ohm standard 3.3 K Ohm on request
- Thermistor measurement: A half bridge ratio-metric measurement . Value returned in mV. Is used for temperature compensation on VW measurements.
- Thermistor excitation: 2.5 V DC 50 ppm /Deg C
-
Input resistance: 10 K Ohm 0.1 % Completion resistor (Standard)
3.3 K Ohm on request - Scan Time: 2 - 24 Sec's 1 to 8 channels depending on sensor operation.
- Long term stability ± 0.05 % FS max. Per year
- Lightning Protection: Gas Discharge Tube
- VW Excitation Range: 400 - 6 K Hz
- VW Excitation Mode: Auto-resonance
- Operating Voltage: 10 - 16V DC
- Ceramic Loudspeaker: VW sensor - Selector switch
Power Consumption
- Scanning mode: 10 mA Duration 24 Sec ( 3 Sec / Chan)
- Display mode: 460 mA Continuous
- RS-485 mode: 2.2 mA Continuous while waiting for commands
- Measuring time warm up response 500 ms 3 seconds per channel depending on the VW sensor being used (Typical)
Software
- VW sensor linearisation: Quadratic Y = A + B.F + C.F2
- Temperature sensor linearisation: Steinhart-Hart, User-selectable via terminal port
- Length of data lines RS-485 0 .. 1000 m
- RS-485 Address mode Supports enhanced addressing 0 .. 9 A .. Z
General Data
- Dimensions (mm): L =260 W = 128.5 D = 38
- Material: Powder coated aluminium
- Digital Port: RS-485, 1200 Baud, 7 bit, N stop bit, Even Parity - other speeds on request
- CE Conformity: CE conformity according to EN 61000-6
- Terminal Port: 9 Way Male - 9600 Baud 8 data, Even Parity, N stop , DTE
- Weight: 400 g