On-site calibration of measuring instruments is often very time-consuming and expensive. This is especially true for applications with several measurands. One example of this is the metering skid, a system for the custody transfer measurement of the amount of natural gas transferred. A global player in the industry from Saudi Arabia has now significantly streamlined the testing process at this point: with the multi-functional CPH8000-P1 calibrator from WIKA, a “calibration laboratory in a case”.
The heart of a metering skid is the flow computer. It processes the information from all the measuring instruments and calculates the exact amount of natural gas that flows to the customer. Natural gas is compressible, so the monitoring of pressure and temperature during gas transfer plays a crucial role.
Verification is the law
Because even small measuring errors can cause noticeable losses in turnover, the measuring instruments must be calibrated regularly. This is usually done at the facility. Each on-site calibration must also be verified in accordance with regulations. This means proving consistent repeatability of the test results and traceability to the assigned references. In addition, the regulations require the test equipment to be approved for use in hazardous areas.
In view of the requirements, the calibration personnel of WIKA customers previously had to use many different pieces of equipment in order to adequately fulfil their tasks. In addition to pressure and temperature calibrators, this included a pneumatic pump for the test pressure, a HART® communicator and a resistance decoder. The on-site calibration cost time and effort accordingly.
Four measuring channels
The natural gas company in Saudi Arabia has reduced this effort in one fell swoop with the CPH8000-P1 portable multi-function calibrator from WIKA. The case-mounted instrument calibrates pressure measuring instruments as well as resistance thermometers and thermocouples. The test pressure is generated with an integrated pump. The CPH8000-P1 has four measuring channels. It can thus perform and display up to four measurements simultaneously. The ATEX-approved version also supplies the test items and reference sensors in the metering skid with voltage (DC 24 V) without danger.
Documentation without problems
The powerful data logger and the very large memory capacity of the calibrator support the user in documenting the on-site calibration. The integrated HART® module transmits all measured values and protocols of the on-site calibration to the control system of the plant for further processing. The unit thus provides all the information relevant for verification.
Detailed information on the model CPH8000 multi-function calibrators is available on the WIKA website. Each instrument has a modular design and can therefore be specified for the respective range of applications. Should you have any further questions, your contact will gladly help you.