The Primex OneVue Temperature and Humidity Sensor employs a precision sensing element for deriving temperature and humidity readings. The sensing element used in Primex OneVue Sensors is supplied by Sensirion AG. Every sensing element is individually calibrated and tested by reference equipment calibrated by an ISO/IEC 17025 approved laboratory. Lot identification is printed on the sensing element and an electronic identification code is stored on an IC chip within the sensor.
The Sensirion data sheet* specifies a long-term drift <0.25% RH/year and<0.02 degrees C/year. With the small amount of drift and lack of clear regulations relating to the measurement of ambient temperature and relative humidity, the standard for replacement is primarily dependent on the sensor application. As the manufacturer, Primex states our Temperature and Humidity Sensor can remain accurate for up to 10 years from the date of first use for many applications.
* Version 4 – May 2014
The statement of traceability (Calibration Certification) provided by Sensirion defines the methods used for calibration as well as the international standards bodies recognizing the methods used, including the “National Physical Laboratory” (NPL) and the “National Institute of Standards and Technology” (NIST).
The specific sensing element used by Primex is Sensirion part # SHT21.
Product: SHT1x / SHT2x / SHT3x / SHT7x Series
Description: Digital Humidity and Temperature Sensors
The above mentioned products are calibrated to meet the specifications according to the corresponding Sensirion data sheet. Each device is individually tested after its calibration.
Sensirion uses transfer standards for the calibration. These transfer standards are themselves subject to a scheduled calibration procedure. The calibration of the reference itself used for the calibration of the transfer standards is performed by an ISO/IEC 17025 accredited laboratory.
The accreditation body is full member of the International Laboratory Accreditation Cooperation (www.ilac.org). Calibration certificates issued by facilities accredited by a signatory to the ILAC Mutual Recognition Arrangement (MRA) are accepted by all signatories to the ILAC MRA.
This provides traceability of measurement to recognized national standards and to units of measurement realized at the “National Physical Laboratory” (NPL) or other recognized national standards laboratories like “Physikalisch-Technische Bundesanstalt” (PTB) or “National Institute of Standards and Technology” (NIST).
Staefa, Dezember 2014
Dr. Felix Mayer
Co-CEO, Sensirion AG
Head of Quality Management, Sensirion AG
2014 © Copyright Sensirion AG, Switzerland