Metrološko ovrednotenje merilnega sistema DEMOS

Anton Nino, Bratina Novak (author), Begeš, Gaber (author)

V članku je predstavljeno metrološko ovrednotenje merilnega sistema DEMOS, ki je bil razvit za spremljanje okoljskih parametrov v notranjih in zunanjih mikrookoljih, predvsem v šolskih učilnicah. Sistem združuje napredne digitalne senzorje in mikrokrmilnik ESP32 ter omogoča meritve temperature, relativne vlažnosti, hrupa, CO₂, VOC, delcev PM in drugih onesnaževal. V sklopu raziskave je bila izvedena eksperimentalna primerjava temperaturnih in vlažnostnih senzorjev SEN55 in SCD40 v klimatski komori, hkrati sta bili ocenjeni njihova točnost in merilna negotovost. Rezultati kažejo, da SEN55 ponuja bolj stabilne in točne meritve temperature in vlažnosti kot SCD40, pri čemer skupna razširjena negotovost znaša 0,50 °C (SEN55) in 0,62 °C (SCD40) za temperaturo ter 4,0 % r. v. in 7,1 % r. v. za vlažnost. Dodatno je bilo analizirano merjenje hrupa, kjer sistem sicer ne dosega natančnosti profesionalnih fonometrov, vendar omogoča zaznavo relativnih sprememb v spektru govora. DEMOS je tako primerno orodje za spremljanje okoljskih pogojev, kjer sta pomembna prostorska porazdelitev in dolgoročno opazovanje

• Language: Slovenian
• Keywords: temperatura, vlaga, hrup, merilni sistem, okoljski parametri
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FE - Faculty of Electrical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: Str. 197-202
• Numbering: Letn. 92, št. 4
• PID: 20.500.12556/RUL-181874
• UDC: 621.317
• ISSN on article: 0013-5852
• COBISS.SI-ID: 256410115
• Publication date in RUL: 17.04.2026

Record is a part of a journal

• Title: Elektrotehniški vestnik
• Publisher: Strokovna zadruga koncesijoniranih elektrotehnikov, Elektrotehniška zveza Slovenije
• ISSN: 0013-5852
• COBISS.SI-ID: 742916

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: English
• Title: Metrological evaluation of the DEMOS measurement system

Abstract

This paper presents a metrological evaluation of the DEMOS measurement system, designed for monitoring indoor and outdoor environmental conditions, especially in classrooms. DEMOS integrates digital environmental sensors and an ESP32 microcontroller, measuring temperature, humidity, noise, CO₂, VOCs, PM, and other pollutants. Temperature and humidity were evaluated using SEN55 and SCD40 sensors in a climatic chamber, and results show that SEN55 performs better in both stability and accuracy. The expanded uncertainty for temperature is 0.50 °C for SEN55 and 0.62 °C for SCD40, while for humidity it is 4.0 % r.h. and 7.1 % r.h., respectively. Noise measurements revealed that although DEMOS cannot replace class 1 sound level meters, it provides reliable trend detection within the speech frequency range. The system is compact, scalable, and suitable for spatial environmental assessment and long-term monitoring, particularly where relative changes and spatial variability are more relevant than absolute precision.

• Keywords: temperature, humidity, noise, measurement system, environmental parameters