On request consumer device can be equipped with factory calibration protocol, which, unlike the protocol state. verification, will accurately indicate the measurement error at various points in the measurement range. Opportunity of alignment by the user, where necessary, especially important for humidity sensors for capacitive sensing elements. Calibration interval for these devices is 12 months. This means that the manufacturer and the state (as issuing authority) warrants that the accuracy characteristics of the sensor within one year of service subject to consumer environments. And now all is lost compare recorded in the operating instructions for any humidity sensor modes of operation with technical parameters used by the sensor. (We will not name specific sensors, the picture typical.) The manual is written to the sensor application range of temperatures from -40 to +80 C. The sensor uses the se company HIH-4010 Honeywell.
In describing the technical characteristics of the se read: "The stability of the parameters is 1,2 % Per year at 50% rh . Hence, for the other humidity, this value could be even greater. We read further: "Operation at humidity above 90% leads to a shift in the characteristics of 3%. More – more: if they contain certain substances in the air, shift the parameters of the se can be up to 15% or more, before irreversible internal damage. How, then, the sensor manufacturer can promise to the consumer his stable job for a year? At Honeywell, as well as many other well-known manufacturers – good humidity sensing element, but it is not simple devices. Treat them gently and not to the year ahead firmly to ensure the immutability of their parameters.
Such guarantees can be given only if written in the manual, the sensor must be operated exclusively under sterile conditions. Or placed near moisture sensors analyzers, counters, dust and close it impermeable cap, if suddenly the composition of the air will be beyond what is permitted. What should I do? What is the solution, say feel betrayed buyer paid for the humidity sensor is twice the price? Try to give a few recommendations: Buy-humidity sensors are only the manufacturers, with metrology equipment for calibrating them with great experience of manufacture and operation of the product using the most modern sensitive elements. -Do not buy without the need for sensors made in the state. Register. Remember that without the annual periodic validation of this record does not make sense, but every year you have to take them in practice, pay to 3400 rub. and hoped that the results of verification will be positive, then the probability is very small. -Check whether the adjustment provided for the humidity sensor consumer and whether it is sufficiently simple and clear. – Together with purchase of the sensor get set salts for adjustment. Aligning with the salt commonly used in Europe. The method is standardized, has high accuracy and low cost. Well, as you can, firstly, at any time check the sensor readings, and secondly, if it must be align. npk Relsib "