36th Issue (April 2023) (1507)

Feature Article

Feature Article 1 - Installation of Residual Current Devices for Fixed Electrical Installations in Village Premises in the New Territories

Residual Current Devices (RCDs) After years of weathering of the earthing systems, earthing conductors of fixed electrical installations in village premises may have problems such as rusting, intermittent connection, loose contact, mechanical damages and breaks, resulting in poor earthing, and hence failure to meet the safety requirements of effective earthing and provide effective protection.

Most of the electrical incidents that took place in village premises in the New Territories involve dual inadequacies, namely poor earthing and lack of residual current devices (RCDs). If a fixed electrical installation in village premises does not have effective earthing connection, the earth fault loop impedance will be too high. When an earth fault occurs in a piece of electrical equipment in the premises and the fixed electrical installation is not installed with an RCD, the earth fault current in the circuit may be insufficient to cause operation of the overcurrent protective device. Coupled with the lack of protection by an RCD, automatic disconnection of earth fault current cannot be achieved, and electrical incident would be resulted.

To prevent such incidents, fixed electrical installations in village premises in the New Territories are required to be installed with RCDs for further protection, in order that automatic disconnection of earth fault current can be achieved even when the earthing is poor. As required by Code 11J of the Code of Practice for the Electricity (Wiring) Regulations, protection by means of an RCD should be provided for fixed electrical installations supplied from overhead line system and fixed electrical installations in premises under the “List of Recognised Villages under the New Territories Small House Policy”. Simply put, owners of premises can meet the relevant requirements by installing a main switch incorporated with an RCD upstream to the electric meter or in the distribution board.

Registered electrical contractors (RECs) and registered electrical workers (REWs) should explain the importance of installing an RCD, while owners of premises should actively employ REC to carry out related inspection. When REWs carry out inspection to fixed electrical installations in any village premises in the New Territories, they should pay special attention to whether the earthing system of the premises meets the safety requirements. In addition to visual inspection, REWs should carry out earth fault loop impedance tests to ensure that the earth fault loop impedance of the circuits meet the safety requirements. If it is found that the fixed electrical installation in the premises is not installed with a main switch incorporated with an RCD upstream to the electric meter or in the distribution board, it should be installed promptly for further protection.

The fixed electrical installation in the premises is installed with a main switch incorporated with an RCD upstream to the electric meter or in the distribution board.

Feature Article

Feature Article 2 - Fault Protection for Electric Vehicle Charging Facilities

Introduction

To promote the use of electric vehicles (EVs) in Hong Kong, the Electrical and Mechanical Services Department (EMSD) has revised Code 26S in the 2020 edition of the “Code of Practice for the Electricity (Wiring) Regulations” ("Code of Practice"), setting out particular requirements for the installation of EV charging facilities. The latest Code of Practice has been fully effective since 31 December 2021. The EMSD also published the Guidance Note on Fault Protection for Direct Current Electric Vehicle Charging Facilities in October 2022 to provide further guidelines on how to meet the requirements for fault protection of direct current (DC) EV charging facilities.

Fault Protection Requirements and Methods for Checking EV Charging Facilities

According to Code 26S(4)(d) of the Code of Practice, except for circuits using the protective measure of electrical separation, each charging point shall be protected by its own residual current device (RCD) of at least Type A. In addition, except where provided by the EV charging equipment, protective measures against direct current (DC) fault current shall be taken for each charging point with a socket outlet or connector complying with the IEC 62196 series.

Mode 3 Charging

According to Code 26S(3)(b)(i) of the Code of Practice, the socket outlet or connector in Mode 3 charging shall comply with the IEC 62196 series or equivalents. Therefore, when EV charging facilities for Mode 3 charging are to be installed, appropriate protective measures against DC fault current shall be taken for each connection point as follows:

An RCD of Type B shall be installed on the supply circuit of the charging point; or
An RCD of Type A shall be installed on the supply circuit of the charging point and protective measures against DC fault current (such as a built-in residual direct current detecting device (RDC-DD) complying with the IEC 62955 standard) shall be provided by the EV charging equipment to disconnect the supply in case of DC fault current above 6mA.

RCD tester

Test adapter for
EV charging equipment

Method for checking the fault protection measures

To ensure that the above RCDs or the protective measures against DC fault current of the EV charging equipment works properly, registered electrical workers (REWs) should use suitable testers to test the charging equipment and its supply circuit by simulating a DC earth fault to see if the protective measure operates effectively. Such testing tools may include the following:
1. An RCD tester that is suitable for testing an RCD of Type B and an RDC-DD (commonly known as an RCD of EV type on the market), and that is capable of applying testing current for DC leakage to simulate a DC earth fault.
2. A test adapter that can be used with an EV charging socket to simulate the connection of the EV to a charging point to be tested and put the charging equipment into a charging state, while the test adapter should also be equipped with a general electrical socket outlet or connection port for connection to an RCD tester to conduct the test.
Tripping characteristics of the protective measures against DC fault current
- For RCDs of Type B complying with IEC 62423, if the DC leakage current reaches or exceeds twice the rated residual operating current, the above RCDs should trip and cut off the current in less than 0.3 seconds.
- For RDC-DDs complying with IEC 62955, if the DC leakage current reaches or exceeds 6mA, the internal or external protective devices of above RDC-DDs should trip and cut off the current in less than 10 seconds. If the DC leakage current reaches or exceeds 60mA, the protective devices should trip and cut off the current in less than 0.3 seconds.

Mode 4 Charging

DC EV charging facilities for Mode 4 charging should comply with the specific requirements for DC EV charging facilities under Part 23 of IEC 61851 (i.e. IEC61851-23). Generally speaking, for a DC EV charging facility, the EV is connected to the AC supply network through an off-board charger permanently connected to the AC supply, with the DC supplied to the EV via a charging cable that is attached to the charger and fitted with a connector in compliance with the IEC 62196 series.

Typical arrangement of a DC EV charging facility for Mode 4 charging

DC EV chargers in compliance with IEC 61851-23:2014 can be classified into two categories, namely (1) isolated DC EV charger; and (2) non-isolated DC EV charger. The fault protection requirements for each of the above are set out as follows:

Isolated DC EV Charger
As the DC circuit on output side of the charger is electrically separated from alternate current (AC) circuit on power system side, which can be considered as a mean of protective measure by electrical separation, protection by an RCD is optional for such charger.
Non-isolated DC EV Charger
As the DC circuit on output side of the charger is not electrically separated from AC circuit on power system side, such charger shall be protected by an RCD of at least Type A.

In addition, DC EV chargers in compliance with IEC 61851-23:2014 are required to be compatible with RCDs of Type A to be installed as specified in Clause 7.6 of the standard (i.e. any RCD of Type A to be installed on the AC supply circuit upstream to the chargers shall be able to be used together with the charger and function safely as intended). As such, an RCD of Type B is not required for a DC EV charger in compliance with IEC 61851-23:2014.

Sample of the Type Test Report and Relevant Test Report for DC EV chargers

Method for checking the fault protection measures

To ensure that DC EV chargers comply with IEC 61851-23:2014 on the classification of different chargers and protection against electric shock, REWs should check the type test reports and relevant test reports of the equipment, and pay heed to the relevant clauses of the IEC 61851-23:2014, including but not limited to the following:

Clause 6.101 on the classification of DC EV chargers;
Clause 7 on protection against electric shock; and
Annexes AA.3.1, BB.2 or CC.4.1 on the requirements for different types of isolated DC EV chargers for protection against electric shock, etc.

For details on how to meet the requirements for fault protection of DC EV charging facilities, please refer to below Guidance Note on the EMSD's website:

Guidance Note on Fault Protection for Direct Current Electric Vehicle Charging Facilities

News-in-brief

News-in-brief 1 - Online Application for Registration of Generating Facilities and Endorsement of Periodic Test Certificate

Introduction

With effect from 30 June 2022, applications for registration of generating facilities (GF) and endorsement of periodic test certificates (Form WR2) may be made online through "EMSD (Regulatory Services) Web-Based Registration Services" and the "iAM Smart" mobile app by mobile phone or computer. Such services allow members of the public and trade practitioners to complete the entire application process (i.e. submission of application, payment and collection of certificate) online without having to visit the EMSD in person, saving time and bringing convenience to them.

Online Application Process for GF Registration

Step one:	The GF owner or his/her authorised person fills in the application form and uploads the documents required, such as the completion letter of renewable energy feed-in tariff scheme and work completion certificate (Form WR1).
Step two:	The GF owner performs digital signing and completes the online payment.
Step three:	The EMSD assesses the registration application upon receipt.
Step four:	After the registration application is completed, in addition to issuing a paper GF registration certificate to the GF owner, the EMSD will also send an electronic GF registration certificate to the applicant’s email address.
For guidelines and requirements on online submission of applications, please visit the EMSD webpage: Online application for Registration of Generating Facility

Online Application Process for Endorsement of Periodic Test Certificate

Step one:	The owner of the fixed electrical installation or his/her authorised person fills in the application form and uploads the documents required, such as the schematic wiring diagram and checklist. As the owners of fixed electrical installations will receive the electronic periodic test certificates by email after the endorsement is completed, applicants are reminded to provide valid email addresses.
Step two:	The registered electrical worker and registered electrical contractor concerned, as well as owner of the fixed electrical installation perform digital signing. The applicant completes the online payment. Please refer to the following flow chart for the detailed online application process for endorsement of periodic test certificates. Flow Chart: For the detailed online application process for endorsement of periodic test certificates [Excel format].
Step three:	The EMSD assesses the endorsement application upon receipt.
Step four:	After the endorsement is completed, the EMSD will send the electronic periodic test certificate to the email address provided by the applicant for receiving the same.
For guidelines and requirements on online submission of applications, please visit the EMSD webpage: Online application for Endorsement of Periodic Test Certificate

News-in-brief

News-in-brief 2 - Supervisory Roles of Registered Electrical Contractors under the Electricity Ordinance

In accordance with section 34(6) of the Electricity Ordinance (Cap. 406), a registered electrical contractor (REC) and an owner of an electrical installation referred to in section 35(3) of the ordinance shall effectively supervise the registered electrical workers (REWs) employed by him. In this connection, an REC should adopt the following measures to effectively supervise the REWs employed by him in carrying out electrical work:

Provide the employed REWs with the safety procedures and method statements on carrying out electrical work;

Provide the employed REWs responsible for supervising other workers in carrying out electrical work with clear guidelines on supervision of workers, including a checklist of documents held by the workers of the sub-contractor(s) (e.g. valid certificates of registration) to be checked on site and tasks to be performed (e.g. inspection and testing, as well as verification that the power supply of the electrical installation concerned has been switched off, isolated and locked out) before arranging workers to work on the installation;

Provide the employed REWs with appropriate and sufficient training necessary for carrying out electrical work;

Provide the REWs and other workers employed with suitable and sufficient personal protective equipment and tools for carrying out electrical work;

Provide the employed REWs with sufficient manpower to carry out electrical work;

Formulate and implement monitoring measures, such as requesting sub-contractors to submit the proofs of qualifications of workers, so as to ensure that they are, by virtue of their knowledge and training, capable of carrying out the electrical work concerned.

News-in-brief

News-in-brief 3 - Safety Tips for Installing and Using "Shower Storage Type" Electric Water Heaters

Do not install shower heads with on/off control valves.
Do not install on/off control valves on outlet pipes.

Do not connect outlet pipes to wash basins or bath tubs.

In recent years, there has been an occasional occurrence of domestic accidents involving "shower storage type" electric water heaters, with most accidents caused by improper installation of heater fittings (i.e. outlet pipes, mixing faucets and shower heads). Please be reminded that the mixing faucets and shower heads installed on "shower storage type" electric water heaters must be produced or approved by the original manufacturers of the heaters. In addition, do not install shower heads with on/off control valves or massage function on "shower storage type" electric water heaters, install on/off control valves on outlet pipes or connect outlet pipes to wash basins or bath tubs, in order to prevent the storage tanks of the heaters from explosion due to excessive pressure.

Those who would like to install electric water heaters should engage a registered electrical contractor and a designated person# as required by the Water Supplies Department (WSD) respectively for the installation of relevant fixed electrical installations and water pipes. To ensure electricity safety, users should adhere to the instructions in the user manuals in using and maintaining electrical water heaters, including switching off the power to the electric water heaters after use and arranging experienced technicians to carry out periodic inspection. If any abnormalities (such as tripping, abnormal sound, etc.) are found when using an electric water heater, stop using it immediately and contact the supplier for inspection and repair.

# For details related to the designated persons, please visit the WSD's website (www.wsd.gov.hk).

News-in-brief

News-in-brief 4 - Safety Tips for Refrigerators

Refrigerator Safety First, Pay Attention to Product Specifications

According to the Electrical Products (Safety) Regulations, the supplier of a refrigerator shall ensure that a certificate of safety compliance [1] has been issued for the product before its supply and the product complies with applicable national or international safety standards (e.g. IEC 60335-2-24: Particular requirements for refrigerating appliances, ice-cream appliances and ice makers).

Samples of the Certificates of Safety Compliance

In addition, members of the public should pay attention to whether the refrigerators to be purchased are equipped with suitable plugs. Generally speaking, the plug of a refrigerator must comply with BS1363 and be fitted with a fuse.

When using refrigerators, members of the public should also pay attention to the following:

If abnormalities are found in a refrigerator, such as abnormal sound or smell, insufficient cooling, or constant running or overheating of the compressor, stop using the refrigerator at once and arrange for an experienced technician to carry out inspection and repair.
Ensure good heat dissipation for the refrigerator. Do not block the area around the refrigerator.
If the refrigerant circuit is damaged, do not use any electrical appliances or open fire equipment nearby. Open all the windows for good ventilation and contact your maintenance agent immediately for follow-up.
Follow the instructions in the user manual to clean the refrigerator and carry out regular inspection and maintenance. Remember not to clean the refrigerator with bleaching solution.

For enquiries on the safety of electrical products, please call 1823 or email to info@emsd.gov.hk.

Plug of a refrigerator

To know more about electrical products safety, please click the link or scan the QR code to visit the Electrical Products Safety Corner.

[1] The certificate of safety compliance (CSC) is a document certifying that the safety requirements of a household electrical product are complied with.
For details, please click the link or scan the QR code to access to the Guidance Notes for the Electrical Products (Safety) Regulation.

News-in-brief

News-in-brief 5 - Report Writing Tips for Competent Persons

Common Problems Found in Competent Person Written Report 2

We have talked about common problems found in the Competent Person Written Report (Written Report) in the 33rd issue of the Electricity News. To further enhance the quality of the Written Report prepared by competent persons (CPs), more common problems found in such reports are listed below for their reference and improvement:

Figure 1

Figure 2

The number of underground cables detected and reported in the measurement record is different from the number of cables shown on the Underground Cable Layout Plan (see Figure 1).
CPs do not use the sample form of the Written Report in Appendix 5 of the Code of Practice on Working Near Electricity Supply Lines (CoP).
Note: To facilitate the preparation of the Written Report by CPs, a sample form of the Written Report was provided in Appendix 5 of the CoP (2018 Edition) for reference and use.
No calibration record/certificate for equipment (i.e. a receiver and a transmitter) used during underground cable detection is provided.
Location information about the underground cable detection provided in the Written Report is unclear or incomplete. (CPs should provide detailed address information, such as XX Nathan Road near lamp post number XYZ).
Cable plans obtained from the electricty supplier more than three months ago are used.
Note: According to paragraph 3.1.6 of the CoP, the working party shall consult/request new cable plans from the electricity supplier 14 working days before the commencement of works, if the plans in hand have been provided for more than three months (see Figure 2).
No attendance record of site personnel participated in the site briefing is provided.

By the way, please be reminded that the working party should keep a copy of the Cable Alignment Record and the Written Report on site until the works are completed without the occurrence of any cable damage. The Cable Alignment Record and/or the Written Report should also be posted on the barrier or railing on the site for site personnel's reference.

News-in-brief

News-in-brief 6 - Enthusiastic Participation in the Technical Seminar to Enhance Electricity Safety and Safeguard Public Well-being

Mr Poon Kwok-ying, Deputy Director/Regulatory Services of the EMSD delivered the opening remarks.

The EMSD has been committed to enhancing the technical standards and safety awareness of the electrical trade in collaboration with trade associations. Since 2001, the EMSD has co-organised the technical seminar every year with the Hong Kong and Kowloon Electrical Engineering & Appliances Trade Workers Union (Trade Workers Union) and the Hong Kong Electrical Contractors’ Association (Contractors’ Association).

With the theme of encouraging the trade to take sufficient preventive measures to avoid incidents and safeguard public well-being, the seminar of year 2022 was held on 22 November 2022 at the EMSD Headquarters. In view of the epidemic, the seminar was conducted mainly via webcasting, but a limited number of seats were provided in the venue for registered electrical workers (REWs) to attend the seminar on site. The seminar attracted nearly 1 000 viewers, a record high for the event.

The seminar was kicked off by Mr Poon Kwok-ying, Deputy Director/Regulatory Services of the EMSD. In his opening remarks, Mr Poon said that the latest edition of the Code of Practice for the Electricity (Wiring) Regulations (CoP) came into effect in December 2021, and REWs should understand and comply with the CoP for safety sake. If the trade follows the CoP and pay attention to electricity safety at work, electrical incidents can be avoided.

The seminar was divided into two parts. In the first half of the seminar, Ir Dr F C Chan, representative of the Contractors’ Association, briefed the participants on electricity safety and the responsibilities of a registered electrical contractor/ worker, while Mr M C Chong, Electrical and Mechanical Engineer of the EMSD, explained the analysis on incidents related to electrical work and suggested solutions. In the second half of the seminar, Mr Ricky Tsang, Senior Consultant of the Occupational Safety and Health Council, introduced the Lockout and Tagout procedures and requirements, and shared experience from electrical accidents.

Group photo of Mr Poon Kwok-ying, Deputy Director/Regulatory Services of the EMSD (seventh right),
Mr Lok Kwei-sang, Chairman of the Workers Union (eighth left),
Mr Choi Kan-man, Chairman of the Contractors' Association (sixth right) and other officiating guests.

For further details about the seminar, please visit the following webpage or scan the QR code:

22.11.2022 Seminar for Members of the Electrical Trade

Ir Dr F C Chan, representative of the Contractors Association briefed the participants on electricity safety and the responsibilities of a registered electrical contractor or worker.

In 2022, the EMSD also resumed the organisation of the Outstanding Registered Electrical Worker Awards Scheme in collaboration with the Trade Workers Union and the Contractors' Association. The scheme is aimed at promoting a work safety culture among the trade by encouraging REWs to improve quality control and work processes, enhancing technical standards and setting examples for the trade. The winners of the Outstanding Registered Electrical Worker Awards 2022 have been elected. They well deserve the awards, as exemplified by their high professionalism and great attention to safety at work displayed in the practical test. To commend the awardees for their outstanding performance, an award presentation ceremony was especially arranged during the seminar.

With the relaxation of social distancing measures, "The Outstanding Registered Electrical Contractors Competition 2023" and "The Annual Technical Seminar 2023" (in physical mode) are scheduled in June and September 2023 respectively. Details will be announced in the relevant Departmental website.

For further details about the Outstanding Registered Electrical Worker Awards Scheme, please visit the following webpage or scan the QR code:

Outstanding Registered Electrical Worker Awards Scheme 2022

Mr Chong Man-chun, Electrical and Mechanical Engineer of the EMSD explained the analysis on incidents related to electrical work and suggested solutions.

Mr Ricky Tsang, Senior Consultant of the Occupational Safety and Health Council introduced the Lockout and Tagout procedures and requirements, and shared experience from electrical accidents.

Mr Chu Kei-ming, Assistant Director of the EMSD, presented souvenirs to the representatives of two nominating organisations, Hongkong Electric Company, Limited and REC Engineering Company Limited.

Mr Poon Kwok-ying, Deputy Director/Regulatory Services of the EMSD and Mr Kwan Sun-chuen, Chairman of the adjudicating panel for the Outstanding Registered Electrical Worker Awards presented the awards to the winners.

Electrical Safety Quiz

1	Which of the following should be done by a registered electrical worker (REW) when carrying out inspection or alteration to fixed electrical installations in village premises in the New Territories? Pay special attention to whether the earthing system of the premises meets the safety requirements. In addition to visual inspection, carry out earth fault loop impedance tests to ensure that the earth fault loop impedance of the circuit meets the safety requirements. If it is found that the fixed electrical installation in the premises is not installed with a main switch incorporated with an RCD upstream to the electric meter or in the distribution board, it should be installed promptly for further protection.
	i ii and iii i and iii All of the above
2	Which of the following appropriate protective measures against fault current should be taken when an electric vehicle (EV) charging facility for mode 3 charging is to be installed? A residual current device of Type AC should be installed. A residual current device of Type B should be installed. A residual current device of Type A should be installed and protective measures against direct current (DC) fault current (such as a built-in residual DC detecting device (RDC-DD) in compliance with IEC 62955) provided by the EV charging equipment. Protective measures against DC fault current should be provided by the EV charging equipment and a residual current device of Type AC installed.
	i and ii ii and iii ii, iii and iv All of the above
3	Which of the following information should an applicant provide when applying for endorsement of the periodic test certificate online? Schematic wiring diagram Checklist Email address for receiving the electronic periodic test certificate
	i ii and iii i and iii All of the above
4	Which of the following measures should be adopted by a registered electrical contractor to effectively supervise the registered electrical workers (REWs) employed by him in carrying out electrical work? Provide the employed REWs responsible for supervising other workers in carrying out electrical work with clear guidelines on supervision of workers. Provide the employed REWs with the safety procedures and method statements on carrying out electrical work. Formulate and implement monitoring measures, such as requesting sub-contractors to submit the proofs of qualifications of workers, so as to ensure that they are, by virtue of their knowledge and training, capable of carrying out the electrical work concerned.
	i ii and iii i and iii All of the above
5	Which of the following is UNSAFE when using a refrigerator?
	Stop using the refrigerator immediately if abnormalities are found. Ensure good heat dissipation for the refrigerator. Disinfect the compartment of refrigerator with bleach. Follow the instructions in the user manual to clean the refrigerator and carry out regular inspection and maintenance.
6	Which of the following is a common problem found in the Competent Person Written Report?
	Competent persons do not use the sample form of the Competent Person Written Report in Appendix 5 of the Code of Practice on Working Near Electricity Supply Lines. Cable plans obtained from the electricty supplier more than three months ago are used. No attendance record of site personnel participated in the site briefing is provided. All of the above.

(Answer：1d, 2b, 3d, 4d, 5c, 6d)

E: Electricity News O: Odilia

E:	Odilia, I know you are very busy at work, could you share with us what you would do to relax on vacation?
O:	I like visiting the countryside on vacation to enjoy the nature. I live in the urban area and occasionally visit friends who live in village houses.
E:	Speaking of village houses, in this issue, we will share the points to note on the safety of fixed electrical installations in village houses. Have you ever heard of the residual current device (RCD)?
O:	Yes, I have. I know that the RCD is a protection device. When an electrical leakage incident occurs, the RCD will automatically disconnect the power supply of the electrical installation to ensure electrical safety. I also know that an RCD should be equipped with a test button and tested at least once every three months.
E:	Oh, you know a lot about in electrical safety. In this issue, we will talk about the information on the installation of RCDs for electrical installations in village houses, please root for us.
O:	Sure!

Electricity News - 36th Issue (April 2023)

Contents

Experience Share

Feature Article

News-in-brief

Electrical Safety Quiz

Readers' Feedback and Update

Experience Share

Odilia shares her insights on electrical safety at village houses

Artiste Odilia

Feature Article

Feature Article 1 - Installation of Residual Current Devices for Fixed Electrical Installations in Village Premises in the New Territories

Feature Article

Feature Article 2 - Fault Protection for Electric Vehicle Charging Facilities

Introduction

Fault Protection Requirements and Methods for Checking EV Charging Facilities

Mode 3 Charging

Method for checking the fault protection measures

Tripping characteristics of the protective measures against DC fault current

Mode 4 Charging

Method for checking the fault protection measures

News-in-brief

News-in-brief 1 - Online Application for Registration of Generating Facilities and Endorsement of Periodic Test Certificate

Introduction

Online Application Process for GF Registration

Online Application Process for Endorsement of Periodic Test Certificate

News-in-brief

News-in-brief 2 - Supervisory Roles of Registered Electrical Contractors under the Electricity Ordinance

News-in-brief

News-in-brief 3 - Safety Tips for Installing and Using "Shower Storage Type" Electric Water Heaters

News-in-brief

News-in-brief 4 - Safety Tips for Refrigerators

Refrigerator Safety First, Pay Attention to Product Specifications

News-in-brief

News-in-brief 5 - Report Writing Tips for Competent Persons

Common Problems Found in Competent Person Written Report 2

News-in-brief

News-in-brief 6 - Enthusiastic Participation in the Technical Seminar to Enhance Electricity Safety and Safeguard Public Well-being

Electrical Safety Quiz

1

Which of the following should be done by a registered electrical worker (REW) when carrying out inspection or alteration to fixed electrical installations in village premises in the New Territories?

2

Which of the following appropriate protective measures against fault current should be taken when an electric vehicle (EV) charging facility for mode 3 charging is to be installed?

3

Which of the following information should an applicant provide when applying for endorsement of the periodic test certificate online?

4

Which of the following measures should be adopted by a registered electrical contractor to effectively supervise the registered electrical workers (REWs) employed by him in carrying out electrical work?

5

Which of the following is UNSAFE when using a refrigerator?

6

Which of the following is a common problem found in the Competent Person Written Report?

Readers' Feedback and Update

Contact Information