PDF《Compact Gas Volume Corrector》

emergency battery for corrector Volume pulses: reed, NAMUR or Wiegand Internal modem

24 V or

230 V power pack COMPACT GAS VOLUME CORRECTOR SYSTEM EC

900 3 Features, archives and logbooks Archives and logbooks The compact gas volume corrector has archives where measured data and events are recorded in compliance with the DSfG standard. These archives can be read out through one of the interfaces via Modbus or DSfG-B. There are the following archives: - Periodic archive 4,442 entries If the measuring period is

1 hour (preset), the memory depth is su?cient for

6 months. The measuring period may be any value from

1 to

600 minutes. - Disturbance archive

600 entries As the periodic archive, but it is ?lled only during the duration of a fault. - Daily archive

731 entries An entry is made at the end of a gas day (adjustable). - Monthly archive

24 entries - Event logbook

600 entries The event numbers are stored. - Event archive

600 entries Apart from events which are stored in clear text, current measured values and meter readings are stored. - Legal metrological logbook

600 entries An entry is made every time a parameter under legal control is changed. - Parameter change archive

600 entries An entry is made every time any parameter is changed. - Load archive

600 entries As the periodic archive, but with its own time interval settable to a value from

1 to

120 minutes. Every entry comprises the date and time of the occur- rence as well as the meter readings and measured values. In the logbooks, not only the time stamp is stored, but also the changes or event numbers. If the maximum storable number of entries for an archive or a logbook has been reached, the oldest values will be overwritten. This does not apply for the legal metrologi- cal logbook (as per PTB 50.7) where a message appears and further parameter changes can only be made after the calibration switch has been opened and the logbook entries have been deleted. Features ? Approval for custody transfer metering The EC

900 has been approved for custody transfer metering in compliance with the European Directive on Measuring Instruments (MID). Its maximum-load display function has been approved by PTB. ? Battery/mains-powered operation The EC

900 can be operated by a lithium cell. Battery life is approx.

6 years with normal operation (input frequency below

1 Hz or use of Wiegand sensors). The battery can be replaced without damaging a seal. In the case of external power supply, it is even possi- ble to use HF NAMUR transmitters. ? Calculation of the K coe?cient The EC

900 PTZ corrector calculates the K coe?cient on the basis of one of the following methods: - GERG 88S (standard) - AGA-NX-19 - AGA

8 Gross

1 It is also possible to provide the K coe?cient as a constant. ? Tari?-device function Maximum and mean values of pressure and tempera- ture, meter readings and events are recorded in com- pliance with requirements for use under legal control. Furthermore, there is an additional data logger where the recording interval (1 minute up to

2 hours) can be individually chosen by the user. ? Explosion protection Whether the EC

900 is battery-powered or supplied with 8.2 VDC, it is intrinsically safe and can be used in Ex zone 1. Devices with an integrated modem or another power supply can be used in Ex zone 2. ? Digital interfaces The following digital interfaces can be used for ex- changing data: -

1 optical interface each on the corrector and the communication module -

1 serial interface, con?gurable as RS