Instruments for construction site monitoring are often used in harsh, and hazardous environments. These instruments contain precision electronics, mechanics, and other sensitive elements that require regular checking and calibration to ensure accurate measurement and compliance with national standards. If the calibration interval is too long, sensor accuracy can drift and lead to problematic and costly delays.
A self-test pulse can confirm if the instrument has been mounted in the right direction but cannot confirm it measures correctly. (Self-test pulse only applies to vibration instruments)
Sigicom recommends that the instruments are calibrated at 12-month intervals. However, if the instruments have been installed in the same location for a long time, and have not been moved or exposed to hazardous conditions, it may be sufficient to calibrate every 24 months. If an applicable national standard requires a shorter interval, this standard applies.
You can find the latest calibration date on the calibration label affixed to your instrument. The calibration date is also included in all data reports and available in INFRA Net. Sigicom can provide the customer with automated reminders when it is time for the next calibration.
The instrument is registered, and its software gets updated as necessary. Below follows a description of how calibration for vibration instruments is carried out.
A “frequency sweep” runs from 1 Hz to 1000 Hz, divided into 60 steps. The calibration program draws a curve over the measured values and compares it with a reference instrument. In case of deviation, the program indicates the necessary actions and carries them out. Manual adjustment is usually not needed. Then a second frequency sweep is run to confirm that all parameters are set correctly. The instrument is then labeled with date and approval. The calibration protocol is sent digitally to the customer.
The calibration routine is computerized and follows a precise course without variations. An accredited laboratory calibrates all reference instruments.
The calibration process normally takes one to two hours, depending on the type of instrument and the number of channels. Additional time may be required for potential firmware upgrades, registration, handling, and document creation. Sigicom strives to complete the calibration process and return the customer’s instrument within a few weeks of its arrival at the relevant calibration laboratory. The biggest variable is usually the current queue time, that is, how many other instruments are in for calibration at the current time.
During calibration, the calibration date is written into the instrument’s memory and included in all data files the device creates. For quick reference, a calibration label containing the last calibration date is placed on each instrument and updated upon each successful calibration.
Sigicom recommends that the instrument be returned to the nearest Sigicom calibration laboratory for an immediate “check as arrived-test”. No adjustments are made until the dispute is resolved.
Sigicom maintains a calibration laboratory in each of its regional offices. Stockholm (Sweden), London (UK), Caen (France), Ottawa (Canada), Breukelen (The Netherlands) and Fort Collins (Colorado, USA). For more information and delivery addresses, see Calibration.