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IOT based micro controller device & Electrical Safety.

Updated: Oct 17, 2023

IOT based micro controller device as an Electrical safety measure.


The Maharashtra Fire Services of Government of Maharashtra is insisting to install an IOT BASED MICRO CONTROLLER DEVICE, claimed to be offering multiple safety measures as per IS732. This article evaluates such a device and brings out the findings about this device.


Note: The Circular CEI 2021/P.No.114/Energy-5, Energy Department, Government of Maharashtra is included in Annex A.


Reference:

1. IS732: Code of Practice for Electrical Wiring

2. IEC 61010: Safety requirements for electrical equipment for measurement, control.

3. CEA Measures relating to Safety and Electric Supply Regulations 2023. (CEA regulation)


1. Government Circular.


The circular explains about one device (called as IOT based micro controller device) offering multiple protective measures as listed in table 1.


Table 1: Safety requirement of IOT device translated from the government notice.

Guidelines for maintaining safe internal power supply in government and private hospitals and public buildings in the state and for maintaining continuity of power supply in these places.


Instructions Appendix:-1


IS regarding structure, handling, maintenance and repair of internal power distribution in government and private hospitals. 732 (2019) - Code of Practice for Electrical Wiring Installations as well as IS 17512 (2021) - Requirements for Electrical Installations in Medical locations and Central Electricity Authority Regulations, 2010 are mandatory to maintain.


It is primarily the responsibility of the hospital administration or the customer to avoid any possible loss of life or financial loss due to short circuit or other electrical faults in the internal electrical system due to fire.


Reliability of power supply is equally important along with security of internal power supply in public buildings and hospitals. Hospital Administration / Consumer to maintain uninterrupted power supply.


-------------------- x ------------------ x ---------------------------


8) Electricity as per Central Electricity Authority (Electricity Supply and Safety Measures) Regulations, 2010:


Accurate diagnosis of various sensitive items due to which short circuit and other electrical faults are likely to cause fire is necessary to keep the system safe. For this, various protection systems mentioned below should be included in the power set arrangement and care should be taken to check that it is in good condition from time to time.


I. Protection to minimize the risk of arcing

II. Short Circuit protection

III. Over current protection

IV. Earth leakage protection

V. Over voltage protection

VI. Under voltage

VII. Phase loss protection

VIII. Phase reversal protection

IX. Consideration during loss of supply to neutral

X. Voltage quality

XI. Detection of Loads with low power factor

XII. Detection of Loads with high harmonics

XIII. Detection of Loads with high inrush

XIV. Detection of unbalanced or asymmetric loads


A specific mechanism is required to accurately diagnose all of the above. At present, if the information about the abnormal conditions (Faulty Electrical Conditions) arising in the structure of the electrical arrangement under the microcontroller plant running on the principle of IOT (IOT - Internet of Things) is collected on the cloud according to the real time, it can be ensured that the protection system is functioning accordingly by retrieving the said data. For this I.O.T. It will be convenient to take preventive measures by collecting the related information through the Tatvar-based microcontroller system and analysing the information available through that system. For this N. A. B. L. Microcontroller devices running on IOT (IOT - Internet of Things) principles certified by NABL Testing lab should be installed in all government and private hospitals and public buildings

2. Fire Brigade Demand


Based on the notice by energy department, the fire brigade department of the government of Maharashtra insist the contents in table 2, while applying fire approval in buildings.


Table 2: Demand from Mumbai fire brigade for new buildings.

IOT BASED DEVICES MICRO CONTROLLER DEVICES


The IOT based Micro Controller Device shall be provided in the electrical installation of the building as per the requirement stipulated in Govt. Circular No. CEI 2021/P.No. 114/Energy-5.


The IOT based Micro Controller Device shall be tested & verified by NABL accredited testing agency/laboratory in accordance with the recognized IS:732-2019 code for practice for Electrical Wiring Installation.


The complete installation of IOT based Micro Controller Device shall be checked & certified by the Chief Electrical Inspector, Govt. of Maharashtra & Certificate to that effect shall be issued, which shall be submitted to this department while obtaining Fire safety Compliance.


The data and the alert generated by IOT based Micro Controller Device shall be monitored by the Building Management System & necessary corrective measures shall be taken by the Owner/Occupier immediately.


The data generated by IOT based Micro Controller Device shall be made available to the Fire Brigade Department as & when required to investigate the cause of fire.

The notice from energy department and the demand from fire brigade, create an impression that the requirement claimed in table 1 and 2 are as per IS732. The following comments in table 3 are made to clarify the subject,


3. Comments

Table 3: Comments about the contents in table 1 and 2.

  1. IS732 is not a product standard,

  2. IS732 contains the methods of design, selection, erection and verification of an electrical installation,

  3. One product offering all safety measures of IS732 is a false claim and is against the fundamental requirements of electrical safety.

  4. Violating the fundamental safety requirements can lead to serious issues defeating the very purpose of providing safety itself".

  5. Locations where the demanded device is installed are vulnerable to electrical accidents.

4. Site Study


Few of the sites, where such a device is installed are being verified. The product is installed in between the incoming meter and the main MCB DB of a residence having a 3 phase TT network. The product is in a small box of approximately 200*200*100 mm, consisting of one incomer 3 pole, 32 amps MCB with a shunt trip and a display for various energy parameters. The product called as Smart Electrical Auditor claimed that it,

  • Identify 20 unique electrical problems and protect against over current, earth leakage, over voltage, under voltage, earth voltage, loose connection, current unbalance, current harmonics, power factor, voltage harmonics short term interruptions, voltage variation, voltage unbalance, inrush current, reverse current, etc.

  • Enable effective correction to complex electrical faults and

  • Reports the root cause of an accident.

On verification it is found that the product is a nonstandard multi-function meter with communication facility. The manufacturer developed an app to monitor the energy parameters and claim that it can offer extraordinary safety measures and named it as "IOT based microcontroller device". The products used in this IOT based device for metering are non-compliant to IEC 61010-1 and hence is a violation of CEA regulations and could create unsafe situation.


5. Examples of the inefficiency in the IOT based device.


Table 4: Examples of the inefficiency in the IOT based device.

  1. IOT device is connected at input supply to an apartment, and it measures the total current of live wires. If an equipment downstream in a sub circuit makes an over current, which is a potential device for accident, e.g. a geyser making an over current, the IOT device cannot measure and disconnect the circuit with which this geyser is connected. The over current in this device can be much lower than the total current measured by the IOT device installed at the mains circuit.

  2. If the IOT based device disconnect the supply due to some reason, the supply to the entire home is disrupted unnecessarily.

  3. Suppose an earth leakage is measured by the multi-function meter in the IOT device, the app decides to trip the circuit or not. This adds delay in protection in comparison to RCCB /RCBO. There's no technical data available at place of installation about its minimum trip time when a fault is detected or the tripping time for various types of faults it claims to protect from.

The examples in table 4 are derived from the information available in the manufacturers catalogue. The claims that this provides 20 safety measures referred in IS732 is false. The client who installed this device requested not to disclose the name of manufacturer of photo of product, hence avoided.


6. Violations of regulation and Standards


The device is misleading the consumers and the authorities that it can safeguard electrical installations from hazards. In actual scenario, the IOT based microcontroller device will remain an illusion. The violations of the CEA safety regulations apply in locations where these devices are installed. Some examples are listed in Table 5.


Table 5: Legal violations of IOT based micro controller device.

  1. Any practice or practice involving materials and apparatus without any specific standards, is a violation of CEA safety regulations Regulation 14(3).

  2. Regulation 33 (2) stipulates that the testing and verifications shall be carried out as per relevant standards. (a) The important parameters involved in such verifications as per standards are insulation resistance as per Regulation 35 and earth fault loop impedance as per Regulation 43 (xi). (b) Every circuit need to be tested once installed and before energisation as per Regulation. Every installation comprises hundreds to thousands of circuits and hence an online verification by a device connected at the mains incoming of the supply claiming to monitor all the downstream circuits is impractical and illogical. (c) Periodic verification as per the relevant standards is also mandated in the Regulation, which is also violated by the IOT based device.

  3. Regulation 33 (3) stipulates that the testing equipment shall be calibrated by a Government authorised or National Accreditation Board for Testing and Calibration Laboratories accredited laboratory at periodical intervals as per the periodicity specified.

  4. IS 732 recommends that the testing devices used in the verifications shall comply IEC 61557, whereas the IOT based device is noncompliant to the IS/IEC standard.

Since the government departments are promoting this unsafe and non-compliant product, in case of any accident due to this unsafe product the accountability shall be with the government, especially the energy department and fire safety department.


The product is in violation to IS/IEC standards and hence violation of CEA Measures Relating to Safety and Electric Supply Regulations 2023.


7. Conclusion and Recommendation:

  • The government departments should withdraw the notices referred in Table 1 and 2.

  • The manufacturer should prove the claims made in their website and catalogues.

  • The manufacturer should test the product and comply it to the safety requirements of IS/IEC standards.

  • As claimed by the manufacturer and in the government notice, test report from an NABL accredited laboratory should be furnished so that the 1. Type evaluation report (Test certificate) demonstrates an unbroken chain of traceability to international standards. It should furnish the ID number issued by the National Accreditation Body (ILAC-International Laboratory Accreditation Co-operation) under ISO/IEC 17020 and ISO/IEC 17025, in the test report itself. 2. The Type evaluation report should comprise the details of uncertainty of reference equipment used for testing. 3. The device passes all the test parameters covered in the Table-1 without exceeding the permissible limits of uncertainty for each parameter as per relevant IS/IEC standards.

  • NABL should act against laboratories providing test certificates based on non-standard devices and claims. Accreditation of such labs shall be withdrawn.

Prepared and published by

​S. Gopa Kumar

President

National Federation of Engineers for Electrical Safety

president@nfees.org


Member in various working groups of IEC TC64, TC 81 and BIS ETD 20, ETD 30, ETD 50 & NBC 2016

​S. Appavoo.

General Secretary

National Federation of Engineers for Electrical Safety

secretary@nfees.org


Former Chief Electrical Inspector

Government of Tamil Nadu.



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