Keeping your instrument performing optimally requires both health checks and certifications

Historically, if you had a single colour measurement instrument in your system, repeatability was less important. As you worked with the current batch of bottle tops or automotive parts, the actual colour was less important than the relevant colour.

That means to say, absolute readings may change from day to day due to temperature or humidity, but if the first biscuit and the last biscuit of the shift was within the required tolerance, everyone in the production and quality departments would be happy.

Today the situation is more complex. The product alone is not the only object measured. Now we add packaging, marketing material and different substrates. Then we manufacture the same product around the country, the continent, or the globe. Customers also have different views on tolerance and expectations with regards to quality, some customers accept goods within a wider tolerance, while others demand almost perfect colour consistency.

Konica Minolta is world-renowned for their high degree of measurement to measurement repeatability and close-tolerance inter-instrument agreement. This means that there is a great level of repeatability from one measurement to the next on the same instrument, but there is also a high degree of inter-instrument and intra-instrument agreement.
We have covered inter and intra-instrument agreement in a previous blog, where we demonstrated the exceptional correlation between a Konica Minolta bench-top Colorimeter with Konica Minolta’s portable and bench-top Spectrophotometers.

This key feature allows customers to compare the colour of their goods from one department to another, or to factories spread around the globe, whether with hand-held or bench-top instruments.

Automotive, food processing, decorative coatings, and plastic goods like branded electrical appliances all benefit from these instrument features. You are no longer required to send physical samples around the country, just compare objects with the appropriate software template, and results confirm the sample colour against a pre-defined target or master standard.

How do you continue to ensure optimal repeatability and inter-instrument agreement?

To ensure your instrument is working within these tight tolerances, for optimum group results, Konica Minolta recommends that an annual instrument certification is carried out at an authorised service centre by qualified, factory-trained service technicians.

It is more economical to send the instrument to the service centre than to have the technician attempt to perform instrument certification on-site.
There are also two main disadvantages of on-site service or  instrument certification:

1. Conditions on-site rarely match the controlled service centre environment and therefore the instrument can only be certificated to wider/weaker level.
2. If any parts or repairs are required, the instrument will have to be taken off-site to be repaired at the service centre and only returned again once repaired and certificated.

Following the annual certification, we recommend that customers utilise a type of verification method or Health Check of their instrument. This is typically done with a ceramic Green Tile or using the Green Tile verification template with SpectraMagic NX.

Performing a health check using a green tile

Ceramics are typically used because they have long-term colour stability if cared for correctly.
The tiles are typically not calibrated as each one is slightly different in colour, but is intended to be used at one site on one instrument. Delivered with your instrument(s) a green tile is immediately measured in as a Target colour, with its shade and serial number recorded for each instrument to be checked.

If during normal production quality measurements, a discrepancy appears, the green tile is then measured against the previously set Target to determine whether the instrument is the cause of the errors. Should the green tile reading closely match the green tile target, you can confidently say that the instrument is measuring and reporting as it should be.

Should the green tile confirm the accuracy of the instrument, the errors in the measurements can then be attributable to other factors:

• Difference in instrument settings between Target and Sample.
• Incorrect or poor measurement procedure.
• Incorrect calibration procedure.
• The actual sample colour is different and the instrument should be trusted.

Usually, a Konica Minolta instrument will not operate if a function is out of tolerance and a notification will appear indicating some type of instrument or measurement error.

We recommend that an instrument health check, using the green tile, should not only be performed when readings appear different but should be repeated on a regular basis, such as once a day, once a week or once a month depending on the instrument usage.

What to do if the target and sample Green Tile readings are out of tolerance?

If the green tile is measured against the target green tile, under the same measurement conditions, and there is a clear difference in the results, we suggest that the instrument is sent to one of our service centres immediately so that our technicians can attend to the issue as quickly as possible.

You can easily inform us of these issues by using our service, inspection and certification booking process on this link.

The sooner these errors are detected, the sooner your instrument is repaired, certificated and returned to your site so that it can continue to perform the tasks you rely on.

Service-Level Agreements are offered, which can include loan instruments, allowing for a smooth certification process and no downtime for you.

Health Check VS  Instrument Certification Summary:

• Certification means the instrument complies 100% with the manufacturer’s specifications.
• Health Check is a local quick method to see if the instrument can repeat a pass or not, in the factory conditions.