Pressure difference transducers VEGA-DD (hereinafter – transducer VEGA-DD) are for converting the pressure difference of gaseous media, including natural gas, with physical and chemical indicators as per GOST 5542-87, to an electric output signal, displaying current readings on an indicator, and their archiving.
Transducers VEGA-DD measure the pressure difference for the following gases:
- natural gas, with physical and chemical indicators as per GOST 5542;
- nitrogen, with physical and chemical indicators as per GOST 9293;
- air, with physical and chemical indicators as per GOST 17433;
- carbon dioxide, with physical and chemical indicators as per GOST 8050;
- argon, with physical and chemical indicators as per GOST 10157.
Transducers VEGA-DD are intended for functioning in systems for monitoring, regulating and controlling industrial process parameters. They can also be used for commercial metering in gas metering units.
Transducers VEGA-DD are used for controlling pressure differences (pressure differentials) in gas supply systems, in industries, and housing and public utilities.
Transducers VEGA-DD provide continuous measurement, archiving and indication of the pressure difference of media.
Transducers VEGA-DD archive and store calculation and measurement results, information about emergencies and tampering with transducer operation, and transmit measured, calculated and archived information to a personal computer (PC) or the information transfer device UPI-1М.
Transducers VEGA-DD have the “Zeroing” function available both through an external interface and directly in the device.
Metrological and basic technical specifications of VEGA-DD transducers
- Measurement ranges of transducers VEGA-DD:
- Admissible basic error limits: ±0.1 % or ±0.2 %;
- Linear conversion of the output signal;
- The maximum deviation of the real conversion characteristic from the rated static one shall not exceed 0.16;
- Additional error caused by the magnetic field effect: ±0.2 %;
- Additional error caused by working pressure change: ±0.02 % per 1 MPa;
- In working conditions, the graphic OLED display indicates the pressure difference value and the pre-set measurement units. In the adjustment mode, it indicates the required data;
- As to climatic exposure resistance, the transducers meet the requirements of design group С4 as per GOST 12997, and are made to climatic version UKhL with location category 2 as per GOST 15150, though for operation at an ambient air temperature and measured environment temperature within -30 to +50 °С;
- transducers VEGA-DD are designed to operate at an atmospheric pressure of 84.0 to 106.7 kPa, and correspond to design group Р1 as per GOST 52931;
- as to resistance to sinusoidal vibrations, they correspond to group L3 as per GOST Р 52931;
- working pressure of measured medium, up to 1.6 MPa;
- transducers VEGA-DD operating mode – prolonged, continuous;
- transducers VEGA-DD is powered from a built-in lithium 3.6 V battery, with an electric capacity of minimum 4 A/hr;
- the battery capacity ensures transducers VEGA-DD operation without replacement for 8 years provided the transducer archives are read no more than once daily;
- transducers VEGA-DD ensures storage information with battery power backup, in the event of an external power supply failure (constant parameters and calculated values are entered earlier), for minimum 10 years;
- power consumption – max. 0.08 W;
- transducers VEGA-DD are designed in the explosion-proof version “intrinsically safe electric circuit і” according to the requirements of DSTU 7113, GOST 22782.5-78, GOST 12.2.007.0‑75;
- the protection degree as per GOST 14254-96 (IEC 529-89) for transducers VEGA-DD is IP65;
- Mass, max. 2.0 kg.
Transducers VEGA-DD is designed as a single monoblock instrument. VEGA-DD’s design provides for sealing. Removing the transducer cover leaves visible damages of stamps in the sealing places.
The electronic unit housing has control buttons.
The graphic OLED display is mounted on the housing cover. It displays information (indication of measured values, and others).
The electronic unit housing mounts the «I/O», connector for connecting the cable with a galvanic decoupler (length 15 m) or the information transfer device UPI-1М.
The valves unit includes the following devices: equalising valve, high-pressure valve and low-pressure valve.
The pipe unions of the high and low-pressure chambers are located on the valve unit housing and marked “+” and “-“, respectively.
|1 – valve unit housing;;
2 – high-pressure chamber pipe union;
3 – low-pressure chamber pipe union;
4 – high-pressure valve;
5 – low-pressure valve;
6 – equalising valve;
7 – electronic unit housing;
8 – OLED display;
9 – l.h button “↵”;
10 – r.h. button «▼/х »;
11 – connector «I/O».