YOKOGAWA vigilantplant DM8, User Manual

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<1. GENERAL>
1-1
IM 12T03A01-02E
1. GENERAL
Density is one of the fundamental physical quantities required when the property or composition
of a liquid sample is being determined in industrial processes. Especially, density measurement
of a sample liquid is indispensable in many industries such as electric manufactures, chemical
industries, oil refineries and food-related applications.
The Model DM8 Vibration Type Density Meter is a higher reliable meter full of operation and
maintenance functions. The meter consists of a detector and a converter. The detector has a
vibrator and an RTD (resistance temperature detector), and outputs detected density signal
(frequency) and temperature signal (voltage) to the converter. The converter is equipped with a
microprocessor to convert the frequency signals from the detector into density values and display
them. It also calculates the density at the reference temperature according to these signals and
digitally displays them. Moreover, the converter outputs digital transmission signals besides
analog transmission signals and is further provided with a variety of functions such as one-touch
calibration, self-diagnosis.
1.1 Standard Specifications
1.1.1 General Specifications
Measurement object: Liquid density
Measurement principle: Vibration density measurement
Measurement range:
Density: 0.5 to 2.0 g/cm 3
Temperature: -10 to 100°C
Distance between Detector and Converter: Up to 2 km
Power supply: 90 to 132 V AC or 180 to 264 V AC, 50/60 Hz
Power consumption: 20 VA
n
Characteristics
(overall characteristics after combing the detector and the converter)
Repeatability: 5 x10 -4 g/cm 3 (for digital output)
1 % of span (for analog output)
Linearity: ±0.5 % of span (when span is 0.2 g/cm 3 or less)
±1 % of span (when span is more than 0.2 g/cm 3 )
Temperature characteristics: ±0.5 % of span/±10°C (Compensating error for changes in the
measuring liquid temperature and detector temperature)
Flow characteristics: ±0.1% of span in the 0 to 5 L/min range
Pressure characteristics: ±0.0005 g/cm 3 /±98 kPa change
Viscosity error: ±0.1% of span in the 0 to 1500 cP range
1.1.2 Detector
(1) General Purpose Detector Model VD6D
Detector construction: Non-explosion protection, rain-proof construction
Case material: Cast Aluminum alloy
Case coating: Epoxy resin, baked finish
Case color:
Jade green (equivalent to Munsell 7.5BG4/1.5)
5th Edition : Dec. 11, 2015-00