EDS Measurement Systems, Inc.

Tag: repair

What does “Repair and Calibration” Entail?
Our repair and calibration services of our ERAG, the Concentricity Alignment Tool (CAT) depend on a detailed inspection of the equipment. Once reviewed, we can provide an exact estimate for the repair and recalibration of your tool. For reference, this is generally in the $2,000 range, but will be more if we find damaged parts.

We are the only authorized repair center for these tools. Unlike a calibration shop that may be able to confirm if the tool measures within specifications, we perform a thorough assessment. The goal is not only to ensure the accuracy of measurements, but to identify and correct problems before they cause a failure in the field. We also maintain our calibration equipment and have it calibrated, traceable to NIST standards.

Please contact us with the serial numbers on a tool, and we can tell you the last time it was maintained.

Initial Assessment and Examination
1. Perform a cursory examination to find any obvious signs of damage.
2. Prepare the heads with the default rub-bars to perform a calibration check.
3. Check the supplied batteries and use replacements if they are depleted.
Calibration Check
1. With each of the heads, we perform the calibration process without making adjustments to get a baseline. The results of this check are included with the calibration certificate.
2. If the calibration is close, we would recommend a basic recalibration, but if it is far out of calibration or aberrant, we recommend a comprehensive recalibration.
3. Check to ensure the lever arm readings are within range on each side to test if the lever arm is bent.
Dismantle and Check Heads

Corrosion can be hidden inside the parts of the measuring heads which can cause the mechanism to bind or not retract fully.
1. Check the body of the head for physical damage that may impact its accuracy or free operation.
2. Check that the tape measure attachment clip is in good working order.
3. Examine the rub bars for excessive wear or scratches that would impact their dimensions.
4. Dismantle each head to make sure all the internal components are assembled correctly and in good working order.
5. Check for corrosion on the internal parts.
6. Check the electrical transducer for damage.
7. Look for damage in the cable. Cut insulation can lead to corrosion and weakness. Severely pinched or crushed sections can cause conductors to short out our break.
Check the Power Supply

A damaged connector like this will function for a while, but at some point, the pins will become damaged from the stresses.
1. Measure the internal voltages to ensure they are within range, and that they have not changed from the previous maintenance cycle.
2. Check if the internal adjustments were changed from the previous maintenance cycle.
3. Examine the dynamic electrical responses to ensure they meet specifications.
4. Physically examine the 15-pin connector for damage or excessive wear.
Check Accessories

The 1/16″ driver bit (center) has rounded edges making it difficult to adjust sideplate screws without damaging them.
1. Collect any loose parts in the carrying case.
2. Return the accessory plates to their standard configuration, then check for missing, worn, or damaged parts.
3. Check the sideplate shims for missing pieces and any creases or damage that change their thickness.
4. Examine the rub bars for excessive wear or scratches that would impact their dimensions.
5. Examine the tape measures, checking that they are working adequately, and that the hooks are not damaged and will latch correctly into the tape measure clips on the heads.
6. Reset the extra-length screw plate to its standard configuration and check for missing or damaged screws.
7. On the hand tools, make sure that they are not damaged, and that the hex tips are not worn down.
Create a Quote
1. Identify any major issues and call them out.
2. List all the parts to be replaced.
3. Provide an accurate cost to bring the CAT back to factory specifications.
February 26, 2026
How Often is ERAG Calibration Necessary?

TL;DR

Annually.

But if you only use the tool once or twice in a year, then every other year.

How Often is Often Enough?

Like any calibration, it’s a matter of risk and confidence. A brand new tool (or one freshly calibrated) offers the highest confidence in the accuracy of its readings. Every day, that confidence level drops a little. Assuming regular use, one could expect the confidence in accuracy to drop to zero after 20 years—nearly any tool with no maintenance for 20 years would almost certainly have inaccurate readings. So between day-one and year-20, there is a point when the confidence drops below some threshold that is acceptable for your purposes.

Anecdotally, we recently had a Concentricity Alignment Tool (CAT) that came in for maintenance that had been in the field for 14 years, and by luck it was still within specifications. But this is certainly the exception. Roughly speaking, over 90% of CATs calibrated annually still meet specifications; that drops to about 75% for tools maintained every other year.

Preventing ERAG Failures

Put another way, there is a likelihood of failure that slowly increases over time, and may be accelerated by each use. Although an on-site dramatic failure would likely be detected (readings drifting as they are being read, blank display, etc.), there are other kinds of failures that we detect and repair during calibration may not be apparent during an alignment job but would be equally detrimental to a correctly executed turbine alignment (readings varying because of a loose cable clamp, nonlinear response of actual distance versus reported measurement, etc.)

ERAG Calibration for Accuracy, Consistency, and Confidence

At EDS Measurement Systems, Inc., we take precision seriously. Our calibration stands undergo an annual check against gage blocks. In turn, those gage blocks are sent to a service that validates them against NIST-traceable standards. NIST—the National Institute of Standards and Technology—is the gold standard for measurement accuracy. Thus, the results provided from a calibration are reliable and accurate.

Another benefit is to make different tools provide consistent measurements. If you used one ERAG on an alignment then a different one the next alignment, the results would be the same. Calibration increases the confidence that measurements are accurate.

ERAG Calibration for Quality Assurance and Traceability

Calibration to NIST standards is often a requirement for quality assurance programs, whether through internal corporate requirements, for industry regulations, or for certifications. By providing a traceable reference point, if there’s ever a question about the accuracy of your measurements, you can trace them back to a recognized standard.

Conclusion

As you increase the time between regular maintenance, the potential for inaccuracy and failure increases. But because each customer uses their tool differently, there is no easy answer. The only way to find out with absolute certainty is to start increasing the time between maintenance and wait for an issue. This would result in additional turbine downtime, either to perform turbine repairs, or until the tool was repaired or a replacement acquired. This does not seem like a wise course of action.

Regular calibration helps identify and correct any drift in tool performance, reducing the risk of errors in measurements. Knowing that your tools are calibrated to a recognized standard gives you confidence in your measurements and results.

February 4, 2025
July 2015 Closing

Please note that our repair and manufacturing facility of Concentricity Alignment Tools (CAT)—also known as Electronic Radial Alignment Gauges (ERAG)—in Rochester, New York, USA will be closed from Friday, July 3, 2015 to Monday, July 13, 2015. We will be sure to notify you if any pending orders will be affected by this closing. Also, please refrain from sending tools for repair or calibration during this time.

June 1, 2015
December 2014 Closing

Please note that our repair and manufacturing facility of Concentricity Alignment Tools (CAT)—also known as Electronic Radial Alignment Gauges (ERAG)—in Rochester, New York, USA will be closed from December 3, 2014 to December 15, 2014. We will be sure to notify you if any pending orders will be affected by this closing. Also, please refrain from sending tools for repair or calibration during this time.

November 14, 2014