Electronic Volume Corrector

Electronic Volume Corrector is a measuring device that converts the gas volume measured under working conditions into the gas volume under basic conditions.
The working state gas volume (Vm) information is scanned through the pulse output of the flow meter or the data output of the encoder, and the sensor measures the gas temperature (T) and pressure (P). According to the set flow meter coefficient, the instrument is usually calculated according to the common (PTZ) method or the fixed compression factor (PT, Z=1) algorithm to calculate the gas volume (Vb) and flow (Qb) under basic conditions.
For PTZ calculation, the K value calculation can be based on SGERG-88, AGA8-92, AGA NX-19, and can be selected through settings.
It also has multiple output interfaces: RS485, binary output, multiple pulse output, 4-20mA current output (optional)

Environment temperature:-25℃~+65℃
Medium temperature:-30℃~+60℃
Atmospheric pressure:70kPa~106kPa
Relative humidity:5%~95%

The device is encased in a durable plastic casing with an IP66 rating. It is furnished with either a (LED) display, which could be a graphic display or a segment display, along with a 6-key keyboard to simplify device operation and show both actual and archived values (in the case of the graphic display option).
The device accommodates several power supply modes. By default, it operates on batteries, yet it can also be powered by an external power source. In the specified working mode, the battery lifespan exceeds 5 years. For gas pressure measurement, a digital pressure sensor is installed at the bottom of the device housing. The temperature sensor on the cable is utilized to measure the gas temperature.
It features a large-capacity flash memory that can store measurement and calculation data for many years for internal archiving. To store these values, the device utilizes several types of internal archives for service and metering purposes.
The device is equipped with an RS485 serial interface for communication with a host computer. The diverse communication protocols installed in the device enable easier connection to SCADA systems. It is also feasible to work with standard telephones, radios, GSM and GPRS modems via RS485 lines.
Moreover, the device is outfitted with an infrared light interface for communication with a host computer, which facilitates the setting of parameters and the reading of historical data via a PC. Additionally, it has an IoT module serial interface design, allowing it to be equipped with 2G/NB/4G IoT modules. It can automatically communicate with the server and initiate networking in the event of an alarm.
The latest technology is employed to ensure the device's high performance, as well as its high durability and operability.

Accuracy Level:0.5
Comprehensive indication error ≤±0.5% Temperature indication error ≤±0.5℃ Pressure indication error ≤0.2% (≥20%Pmax, within -15℃~+65℃)

Pressure Sensors
Maximum working pressure Pmax: upper limit of sensor range: 0.5, 1.0, 1.6, 2.0, 2.5, 4.0, 6.0 (MPa absolute pressure).

Input Signal
A.Flow pulse signal: high frequency signal (0.2kHz, Vcc=3V), low frequency signal (0.01m³/0.1m³/1m³/10m³, Vcc=3V). B.Digital temperature signal: I2C digital communication interface. C.Digital pressure signal: I2C digital communication interface.

Output Signal
A.Mechanical pulse signal: amplified and shaped by the preamplifier, the flow pulse signal is output (for flow meter calibration). B.Quantitative pulse signal: 0.1³, 1³ or 10³ corresponds to a pulse 0C gate output. C.Battery undervoltage alarm signal: high level at ordinary times, low level when the battery undervoltage alarm occurs, 0C gate output. D.Flow/pressure alarm signal: low level is output when the instantaneous flow/pressure is lower or higher than the set value, high level at ordinary times, used to monitor abnormal data. E.Current output: The current analog quantity corresponds to the working flow, standard flow, pressure or temperature of the corrector, 4mA corresponds to the lower limit setting value, 20mA corresponds to the upper limit setting value, and supports two-wire and three-wire output.

Data Storage
A.FLASH data storage count, hour count number 4320, day count number 1095, month count number 120. B.Data includes temperature, pressure, instantaneous flow, cumulative amount, time, various abnormal alarms and other information. C.The recording time interval can be set to facilitate historical data query; when the power is off unexpectedly, the data is automatically saved. D.The upper computer software can query historical daily records, important coefficient modification records and fault alarm records through the infrared interface/485 interface.

RS485 Communication
A.Adopt photoelectric isolation RS485 interface (communication rate: 4800bps, 9600bps, 19200bps; communication mode: half-duplex, 8 data bits, 1 stop bit, no parity check). B.ModBus-RTU protocol.

Electrical Protection
A.Double isolation of internal power supply: DC24V power supply is isolated from the housing and internal processing circuit, and can withstand DC500V/minute impact. B.DC24V power supply is resistant to ±500V, 10ms strong interference impact. RS485 communication is isolated from DC24V power supply and housing, and can withstand DC500V one minute impact. C.DC3.6V power supply has anti-reverse connection protection. D.RS-485 communication port has transient voltage suppression function, lightning protection, and anti-static discharge impact. E. Adopting photoelectric isolation and two-wire current loop, it can resist 500V, 10ms strong interference impact. F. Add 3D anti-disassembly function, and the meter can actively report to the platform after moving and tilting.

Detection Alarm Function
A. After magnetic interference occurs on site, an alarm is displayed and the event and time are stored, and the event and time are reported actively. B. Real-time detection of the open and closed status of the corrector, dynamic password is required to change parameters, and the event and time are stored. C. 3D anti-disassembly function, when the total working condition is greater than 2 times the maximum flow rate, the 3D anti-disassembly function is enabled, and when the tilt angle of the meter end detection corrector is greater than 35 degrees (adjustable), the event and time are recorded and stored.