Why do we Calibrate?

What is Calibration?

Calibration is the comparison between measurement results of a device (unit under test) and another (standard) device with known or assigned values. Thus calibration only means recognizing the differences, whilst adjustment also means taking the necessary corrective actions to bring the unit under test into a defined tolerance.
Calibration should not be confused with the instruments white & dark calibration. Dark and white calibration of an instrument is performed on a daily basis by the user, utilizing the zero calibration box and the white calibration plate. These two calibrations are necessary for the instrument to work within a defined reflectance range. However, the white calibration plate may also change over time and therefore a certification calibration service should be carried out once a year by an authorised service centre.

What is Maintenance Service?

While calibration only covers the recognition of the instrument’s condition, a maintenance service will assure that these conditions are within the defined specifications. Maintenance includes cleaning of the instrument, preventative maintenance and replacement of parts such as the xenon lamps as well as any re-adjustments necessary should the instrument not reach the specified accuracy. Every maintenance service also includes the calibration of the instrument to ensure that the repairs and maintenance were conducted properly and the instrument is in full working order.

What is the recommended calibration interval?

Deciding on an interval for inspection or calibration depend on several factors. Some instruments are used in a laboratory or clean room environment which is mostly temperature controlled. Other instruments are used for quality control in a production line with harsher environmental conditions such as dust, humidity and a high number of measurements every day.

Konica Minolta recommends a calibration and maintenance interval of 1 year, which has been found to be suitable for most applications.
There are processes that companies can implement that will inform them about the health of the instrument. By implementing a Green Tile process, companies can quickly verify the performance of the instrument to see whether the instrument should be sent in for certification.

How are Konica Minolta instruments checked and adjusted?

Procedures and tools for checking measuring instruments are strongly dependent on the type of instrument. As Konica Minolta has measuring instruments for a large range of different applications, the range of tools to be used is also very wide.

Konica Minolta utilises multiple standards for light and colour as well as for size. Of course, all of the standards used are traceable to national or international higher level standards. Details can be found in the traceability area where traceability charts for each kind of instrument are also available.

What is Traceability?

Traceability is the process established to relate each standard object or measuring instrument to national standards through calibration to a higher standard.

For high-accuracy measuring instruments, even small deviations from national standards may cause problems. To avoid such problems, maintenance of Konica Minolta’s in-house standards is performed by periodically re-calibrating each standard to Japanese national standards or other international standards. These standards are selected according to the functions of the Konica Minolta products being sold.

National Standards

The national standards of each country are similar and often related by international agreements. These standards are maintained by National Institute of Standards and Technology (NIST) in the United States, the National Physical Laboratory (NPL) in the United Kingdom, Physikalisch Technische Bundesanstalt (PTB) in the Federal Republic of Germany, Institut National de Metologie (INM) in France, etc.

In order to ensure the accuracy of Konica Minolta products, Konica Minolta has established a system wherein the measuring instruments and other equipment used as in-house working standards are periodically re-calibrated utilising higher standards, traceable to national standards, which have been established and are maintained by industrial standards organisations.

New Instruments

New instruments are delivered with a yellow manufacturers Inspection Certificate. While this is not a calibration certificate, it certifies that the instrument has passed Konica Minolta’s stringent quality checks prior to shipping. This certificate is valid for one year after which a Calibration Certification Service is required to renew the certification status. If you require a calibration certification now, this would have to be carried out by our workshop and charged for, but this is rarely a requirement as the Instrument will most often report an error message if it is out of calibration.

NOTE: Certification is a bureaucratic procedure which lapses after 12 months. It does not include SERVICE.
Calibrations can be carried out more frequently than 12 months, but Certifications are valid for a 12 month period.
Inspections and Service can be carried out at any time if users are not sure about the Instruments performance.
Customers can purchase our  Chromacheck “Health Check” tile and software product. While not being a Certification, users can ensure that the instrument is still  performing within tolerance, as well as print reports and keep a log.