Calibration
Frequently Asked Questions – Calibration
What is a Strainsert Force Calibration?
A Strainsert Force Calibration is a controlled process where certified technicians apply multi-step known loads to a sensor and/or sensing system installed in a force calibration machine. The multi-step loads are applied at even intervals throughout the sensor’s measurement range and the applied load and the corresponding sensor output are recorded. This load/output recording establishes a relationship between known load and sensor output and is listed on the Calibration Certificate.
What is the purpose of the information on a Strainsert Calibration Certificate?
The Strainsert Calibration Certificate lists all data points recorded during the Force Calibration, includes a “Traceability” statement to the specific industry standard the calibration was performed in accordance with, and specifies the time period until the next recalibration is due, all of which can be used to support an audit or confirm validity of measurements as sensor was/is within the calibration interval.
The data listed is used to generate the Best-Fit-Straight Line (BSL), shown on the Cal Certification, and the BSL best fits the sensor’s data from zero to full scale, to maximize the sensor’s measurement performance. The BSL is commonly used by our customers to scale the instrumentation paired with the sensors.
The data is also used to calculate the sensor’s measurement performance specifications demonstrated during the calibration and shown on the Cal Certificate. Listing the data also allows our customs to use the actual data points for alternate data-fitting techniques.
How long is the calibration valid?
NIST recommends a one year calibration interval. Strainsert calibrations are traceable to NIST and valid from one year from the date of calibration. Strainsert lists the calibration expiration date on the product calibration sticker and/or the calibration certificate. An in-place calibration may extend this period if your internal quality requirements allow. For details, see below FAQ “Can the time for recalibration be extended?”
Can the time for recalibration be extended?
Yes, by performing an in place calibration using a reference load cell, known load or other repeatable methods. You can establish a specific procedure that can be used to evaluate the performance of your sensor. Calibration extension should be included in your quality polices which dictate requirements for calibration extension in accordance with your measurement requirements and quality policies.
What does in place calibration mean on my customer drawing?
The in-place calibration refers to the application of a known load to the transducer after being installed into the final assembly. Variations between the calibration fixtures and final assembly components can result in variations from the factory calibration data. An in-place calibration is recommended to quantify and account for these variations in order to optimize measurement performance.
How can I get a copy of my calibration data?
We provide an online tool on our website where customers can look up and download their calibration certificates. Navigate here to and follow the posted instructions to get your calibration data.
What is a Shunt Calibration Value, and how is it used?
The Shunt Cal Value shown on the Strainsert Calibration Certificate is a value that is measured and recorded when a specific resistor is placed across two legs of the sensor bridge circuit, which effectively “shunts” the circuit and electrically simulates a loaded condition on the sensor, with no actual load applied.
The resistor value is selected to simulate an output between 60 and 80 percent of the sensor measurement range. By placing the specified resistor across the same legs shown on the Calibration Cert, our customers can generate the shunt value and use it to scale the Instrumentation receiving the sensor input. The shunt value can also be used to verify proper operation of the sensor and/or sensing measurement system, if needed.
How do I return my parts for repair and recalibration, receive an RMA, or quote?
To receive an RMA and/or calibration quote, please complete our online RMA request form: Strainsert Online RMA Request
Once submitted, you will receive a confirmation email with return shipping instructions, and a Strainsert Sales Representative will contact you shortly with your quote.
Contact the Repair Department at 610-825-3310 or by email to customerservice@strainsert.com with any questions.