Calibration Procedure, imc Test Plan (Manufacturer’s Specification)


According to what standards do you calibrate your instruments?


At the moment, adjustment and calibration operations by imc are steps within an overall production process or a service; this means we have no separate inspection laboratory but rather so-called adjustment and inspection stations. The processes and procedures are set out in a protocol in the test instructions and test planning as elements of our Integrated Management System. All the processes are procedures developed by imc itself.

All calibration and adjustment procedures used at imc within the framework of our type testing are developed, validated and optimized for serial inspection with the goal of achieving the greatest precision economically justifiable. In this context, the reports of measurement values are at the same time a certificate and an inspection plan (manufacturer’s specification). It is easy to develop customer-specific inspection plans on this basis; imc is happy to provide support in doing so.

In designing the measuring amplifier, the procedures for its adjustment and calibration are also developed at the same time and verified in the type inspection. One part of the procedure is to adjust various parameters due to their dependence on properties of components and on the running temperature; additional parameters such as the sampling rate selected or the selected filtering may not affect the measurement precision according to design targets.

The resulting acceptance tests include procedures for the serial production and servicing, which reflect an optimum balance of test precision, standards conformity and economic viability.

In our “Calibration” type test, we use the following standards, among others:
The series of standards VDI/VDE/DGQ/DKD 2622: Calibration of measurement equipment for electrical quantities, describes fundamental calibration procedures.

DKD 2622 Blatt 5 describes calibration of function generators
DKD 2622 Blatt 11: Calibration guidelines for spectrum analyzers
DKD 2622 Blatt 20 describes the calibration of DC voltage measuring amplifiers

Additional standards and guidelines:

DKD-R 5-5 regulates the calibration of temperature indicator devices
DKD-R 6-1 regulates the calibration of pressure measurement modules
Power network quality, voltage quality: EN 50160 and DIN 61000-4-30

Does calibration also include adjustment/balancing?


Yes. Calibration by imc includes calibration upon receipt (determining actual values, deviations beyond tolerances are noted), a brief function check, adjustment and calibration for release.

You receive a manufacturer’s calibration certificate without measurement values (lab reports optionally available).

The imc system inspection includes a total functionality inspection from the manufacturing perspective, which is able to reveal certain latent errors. As a customer, you receive a service report.

Upon request, the service “only calibration” is available (no adjustment, no subsequent function testing) or only function testing (system inspection). Since 2005, we have included the following items in our price list:

  • Calibration (includes: calibration upon receipt, manufacturer’s calibration certificate as per ISO 9001)
  • Adjustment (includes: calibration upon receipt, adjustment, calibration for release, manufacturer’s calibration certificate as per ISO 9001)
  • System Inspection (includes: system inspection, function checkup, service report)

The imc calibration package which we recommend and which enjoys our customers’ approval consists of the combination of Adjustment and System Inspection .

Can only individual channels be calibrated?


Upon request, we can calibrate only individual channels according to a customer’s inspection plan.

The imc DEVICES or imc CANSAS user’s interface allows correction values for the offset or for calculation of special characteristics to be saved for subsequent use in particular applications. We use this capability in our own test station applications, for example.

Adjustment of individual channels with permanent recording of correction values in the module storage is generally either not possible or very costly, so only whole systems or modules can be adjusted as a whole.

Furthermore, the elaborate test equipment administration for complex measurement systems, in which only individual functions are adjusted or calibrated, deserves mentioning.

If you have any special wishes, please feel free to communicate these to our hotline.

Is a function test always performed?


The best function test is the system inspection recommended by imc:

A function test of the entire device is conducted (e.g., digital input/output, current supply, analog outputs, depending on device configuration).

Additionally, each device is subjected to an individual final inspection (function test and a measurement check of individual channels using other calibrators); this final inspection can be made to take account of customer-specific or device-specific prerequisites or conditions (for instance, the characteristics of a special MIC-channel can be checked at this stage). The final inspection is documented internally by imc; the customer receives a service report.

Why should there be a system inspection in conjunction with every repair or calibration?


The device is returned to the user completely tested (and having been repaired, if necessary)!

The imc System Inspection is the best and most reliable 100% function test, which is also able to reveal latent errors.

In the course of repairs, re-adjustment is often necessary due to an error found or to a replaced component.

Example: power supply unit reported as defective.
Error profile: defective input channels strain the power supply unit.
Plus: DAC (analog output) channel 2 defective.

Why does an imc calibration take so long?

Typically, imc’s processing time for calibration / adjustment, or System Inspection is 7 to 10 business days, due to the high precision of the inspection and to warm-up times. Additionally, shipping paperwork, consultations about any unanticipated repair work etc. all take time. To avoid downtime, it is important that service orders be determined clearly before the equipment arrives at imc.

If you suspect that your device is defective, or if you need calibration or a system update or reconfiguration, it is necessary in any case to contact our hotline prior to shipping.

The hotline will provide you with an RMA (return merchandise authorization) number.
To make this procedure easier, you can download a form from the Internet to send us by fax or email. Or simply give us a call!

Please do not ship any device without previously contacting us and receiving an RMA number.

Within the framework of a service contract, definite delivery dates or express service can be arranged!

Can the report of measured values be provided in electronic format?


Upon request, we can also generate a report as a PDF file. Please note that a complete device report can consist of over 300 pages.

Pursuant to a service contract, we can place the report in the Internet for downloading. Toward this end, we will naturally set up a password-protected location.

I received two calibration certificates, which one is correct?

The imc calibration includes an input calibration (determination of the actual values, for deviations outside the tolerance you will be informed), a short functions test, a renewed balance and a subsequent output calibration.

The log record of the initial calibration is marked with "[Calibration certificate number] _C". The log record after the adjustment and recalibration is marked only with the “[Calibration certificate number]".

Why is calibration by imc so expensive?


All of our customers face cost pressures and for this reason the running operating costs for service and system maintenance are an issue. There is often some confusion for the user (whose boss administers the budget) and for the internal or external calibration laboratory. Until 2003 there actually was some confusion affecting our statements and ambiguity in the terminology used (e.g., calibration... what does it mean?)

In response to this situation, we have overhauled our price list and the terminology used in it:
-    System calibration = System Inspection + calibration (upon receipt) + Adjustment
-    System Revision = Inspection plus maintenance plus update
-    System modification = includes System Revision

We also have adopted new service items into our program such as system maintenance, express service, warranty extension and personalized service contracts, and in consequence the whole program has been up and running smoothly for three years, as attested by very positive feedback.

Calibration by imc is no more expensive than by a calibration laboratory, for example. Quite the opposite: by offering the total spectrum of service from one source, we can save you time, money and trouble!

We challenge you to compute the ratio of the last three years of service costs to the purchase costs!
“We protect your investment!” is our proud motto. Test us out!

Standards and references


Management systems, test equipment monitoring, terms (see also
•    DIN EN ISO 9000 ff: 2000: Qualitätsmanagementsysteme
•    QS 9000 3rd edition (1994): Quality Systems Requirements QS 9000 (Chrysler Corp., FORD Motor Corp., General Motors Corp.)
•    ISO/TS 16949 (2002) Forderungen an ein Qualitätsmanagementsystem (dt. Übersetzung in DIN Fachbericht 78)
•    VDA 6.1: Forderungen an ein Qualitätsmanagementsystem VDA Band 6 Teil 1 (Verein der Deutschen Automobilindustrie e. V.)
•    DIN 55350-11 (1987): Begriffe der Qualitätssicherung und Statistik; Grundbegriffe der Qualitätssicherung
•    DIN: Internationales Wörterbuch der Metrologie (1994)
•    DIN 1319-1:1995: Grundlagen der Meßtechnik - Teil 1: Grundbegriffe
•    DIN EN ISO 10012 (2004): Messmanagementsysteme - Anforderungen an Messprozesse und Messmittel
•    DIN EN ISO/IEC 17025:2005 Allgemeine Anforderungen an die Kompetenz von Prüf- und Kalibrierlaboratorien (ersetzt EN 45000, setzt ISO Guide 25 um)

Calibration guidelines for electrical measurement equipment

•    DIN ISO 10012-1: Messüberwachungssysteme
•    ISO 8402 (1986): Qualität Begriffe
weiterhin:  DIN 55350 T 11-15, 17, 18, 21-24, 31 (Begriffe) + DIN Taschenbuch 223

DKD Guidelines, miscellaneous (see also
•    VDI/VDE/DGQ/DKD 2622 (Entwurf): Kalibrieren von Messmitteln für elektrische Größen (beschreibt allgemein Kalibrierverfahren)
Blatt 3: Kalibrierrichtlinien für Digitalmultimeter
Blatt 4: Kalibrierrichtlinien für Oszilloskope
Blatt 5: Funktionsgeneratoren
Blatt 11: Kalibrierrichtlinien für Spektrumanalysatoren
Blatt 20: Kalibrierung von Gleichspannungsmessverstärkern
•    DKD-R 5-5 regelt die Kalibrierung von Temperaturanzeigegeräten
•    DKD-R 6-1 regelt die Kalibrierung von Druckmessmodulen
•    DKD-3: Angabe der Messunsicherheit bei Kalibrierungen
•    DKD-4 (1991) Rückführung von Prüfmitteln auf nationale Normale
•    EA Richtlinien (European cooperation for Accreditation of Laboratories):
Übersicht: DAR-INF2, z. B.
DAR-EM6: Interne Audits und QM-Bewertung in Laboratorien
DAR-EM32: Anleitung zur Akkreditierung nach ISO/IEC 17025
DAR-EM23: Sammlung von Begriffen
•    DIN V ENV 13005: Leitfaden zur Angabe der Messunsicherheit beim Messen (identisch mit Guide to the expression of uncertainty in measurement = GUM)
Quality on the Web
•    QM-Infocenter of the publisher Hanser (Quality and Reliability)

DIN 31051 of 2003 defines maintenance including weak point analysis along with pursuant measures; to see the summary click here.