How often do I need to get my electronic flowmeter recalibrated?

The answer is it depends. It depends on how often you use it. It depends on the environment it has been exposed to. It depends on what your company's, industry's or government's regulations on recalibration are. It depends on whether you have accidentally dropped or banged the device. It depends on how confident you are of the results your are getting.

All instruments degrade with time Most measuring devices drift out of tolerance, and some devices need more frequent calibration than others.  The reasons depend on the technologies used in the device and where the device is being used.  When the device is primarily electronic in nature, the resistors, capacitors, and solid-state components that comprise it will deteriorate with time and exposure to heat, cold, and radiation.  As a result, the accuracy of the measurements made by the device also degrade with time until its specifications are exceeded.  Usually, the calibration process can compensate for this degradation through electrical adjustments to the device.  When calibration cannot bring the instrument back into specification, some repairs or part replacements may be needed.

Restek spent a lot of time developing and testing our Proflow 6000 flowmeter.  Under the controlled lab conditions we subjected our devices to we found that our devices stayed within acceptable calibration ranges for at least a year.  However, not all customers use or store the devices in the same way in which we tested them.  Therefore it is up to customers to determine there own frequency of testing.

When customers return devices for recalibration the collection of as-found data gives a good snapshot of how out of calibration a device is (this data is given in the recalibration certificate).  In most cases one or two calibration points are slightly out of range.  This is a good indication that the device was still providing accurate data up to that date.  If, however, the as found data shows significant drift from the calibration then it is an indication that there is damage to the flow sensor manifold.  In our experience this has occurred from exposure to too high a flow rate, even it if is a short burst (always establish flow before applying the flowmeter to measure the flow), or that the device has been dropped or banged.

To always get the most accurate flow measurements, contact Customer Service to send in your flowmeter for recalibration (cat.# 22656-R).