FAQ: Recalibration of Alicat Device

FAQ: Recalibration of Alicat Devices

When do I need to get Alicat device calibrated?

We recommend sending your unit back for yearly calibration. This uphold your lifetime warranty and allows our service department to check for any damage to the device. Over time minor physical changes to the laminar flow element and pressure sensors inside the device and particulate deposits can cause the instruments calibrated flow curve to inaccurately represent the actual characteristics of the flow path. With an annual recalibration, instruments are brought to their optimal calibration specifications and, if need be, can be cleaned.

what is included in an annual recalibration?

Every recalibration starts with an evaluation. Our service technicians will double check analog signals, setting, sensor health, LCD functionality, threads and even cosmetic issues like a scratch on the display.

After carefully evaluation, our service technician will log “as found” data showing how precisely calibration the unit was when it arrived. The device is them compare to our local barometric pressure and a NIST traceable standard and calibration adjustments are made to achieve the closest  to ideal calibration possible. If anything is noticed to be out of sync, we work with the customers to make sure they understand the condition of their Alicat and how we will recalibrate and, if needed, repair the device.

 Additional benefits of annual recalibration 

When a device is sent in for recalibration it is an opportunity not only to maintain the quality and precision of the device, but also an opportunity to update firmware or, if your application needs have changed, the perfect time to work with our application engineer to find a solution that allows you Alicat to adjusted oe even customized to meet your evolving needs without the hassle and expense of buying a whole a new instrument. many reconfiguration options are available for Alicat device-from updating the display to changing the flow range.

On the calibration certificate

Annual calibration includes a NIST traceable calibration certificate with before and after recalibration data. On the calibration certificate, we list certain parameters and conditions related to the calibration:

  • P/D/I values: these are the default turning setting on the device. Note: most units will only have P and D settings.
  • Process gas: The pre-selected gas from the gas menu. This can be changed through the front panel or during recalibration.
  • Calibration gas: The gas used to calibrate the unit. Unless a customer specifically asked for an “actual gas calibration” we typically user air.
  • Rage: The full scale range of the unit. since we can configure device with custom range, this may not match the body size found in the part number.
  • Gas temperature: The temperature of the gas that was used to calibrate thee device at our facility.
  • Ambient humidity: The humidity of our facility at the time of calibration.
  • Calibration procedure/rev#: The standard procedure and revision used to calibrate the gas.

Below this there is a list of of standard tools used to calibrate the unit. Every standard tool used to calibrate the units has an associated calibration chain, to keep all units NIST traceable. This list shows our standard tool’s name, that tool’s calibration due date, manufacturer and model number and uncertainty. Some units listed in this section are Alicat units. These are primary transfer standards, with high accuracy calibration. They are used for calibrating device to our standard (as opposed to “high”) accuracy procedures.

For recalibrations, you will also get a found and as left data. This lets you know if the unit was in spec when it arrived at the calibration facility, and if not, which points were out of tolerance. This also shows the uncertainty, calibration pressure and unit of measure. In the “as found” and “as left” section, the “U.D.T” is your Alicat device being calibrated and “Actual” is reading from the high accuracy device it is compare to. The outputs are the analog input and outputs.

How do I get recalibration from Alicat?

To order a calibration through, contact us for more information.

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