You would think that if you purchase a new EV charging point, it would be safe for use by company employees! There are a number of reasons why this may not be the case, especially with unfamiliar technology.
Provision of Electric Vehicle Charging Equipment (EVCE) for company owned/employee owned vehicles is covered by the PUWER 1998 and Electricity at Work Regulation 1989 – due to the risk of electrocution.
Before putting equipment into service, Users must verify that they have purchased equipment that is suitable for its intended use – Regulation 4(1), it follows then that the specification / purchasing process requires clear understanding of what is being purchased, the standards the equipment should conform to and any specific safety issues associated with the installation, use, test and maintenance of the equipment.
With new technology it is easy to lose sight of the basic steps that are required to ensure staff are not put at risk through poor equipment specification, faulty installation / maintenance and or inadequate training on the safe use of the equipment. Prior to the publishing of the Electric Vehicle Charging Equipment Installation Code of Practice this year, there was no recognised guidance available for installers other than the international standards, leaving companies in a difficult position with regard to their legal responsibility under the aforementioned regulations. Most regulations/codes of practice are not retrospective, however the legal situation still applies in that if it was not safe when it was installed – it is still not safe now. It is worth checking your installation documentation obtained from the EV installer, against the current code of practice. If you have any concerns contact the EV installer.
See Table 1 for summary of the charging methods -The BEAMA guide gives a detailed explanation.
EVCE Specification /Purchasing
The Code of Practice for Electric Vehicle Charging Equipment issued by the IET in February 2012, sets out requirements for EV charging installations. For example section 8 details requirements for Commercial and Industrial locations; section 8.5 covers RCDs, in which it states Type A RCDs are preferred (8.5.3).
Battery chargers used on plug –in electric vehicles (PEVs) can produce high levels of harmonic distortion, due to the technology employed and the nonlinear loading of the supply during charging. Standard AC RCDs are only designed for use on supplies with standard 50Hz waveforms.
Check the type of RCDs that your EVCE supplier intends to use, some EV charging points are supplied with basic Type AC RCDs. Charging circuits interfere with the AC waveform affecting the operation of standard RCDs. Single phase EV charging points fitted with standard Type AC RCDs[1] may not operate safely under certain fault conditions, exposing the employee to a high risk of electrocution in the event of an insulation fault. This situation should be addressed in the new IEC standard (60364-7-722 special installations-supply of electric vehicles) currently in draft, but it will take some time to filter through the various committees and down to street level, where it is required.
See Table 2 for a summary of Charging modes and possible residual currents based on the charging mode technology.
The Government specification issued by the OLEV for e car charging specifies Type A for Mode 3 single phase charge points. For mode 3 and 4 three phase EV charging, International car manufacturers already specify Type B RCCBs for the Projects / Installations that they are involved with, ensuring that they are covered legally with regard to their purchasing / installation specifications and more importantly their customers safety.
RCDs are classed as a 2nd line of defence (see EWR 8. 138), RCDs will not prevent the risk of electric shock but can reduce the risk of death or serious injury if selected, installed and maintained correctly. Duty Holders should note that offences under Regulation 4 & 8 are covered by Regulation 29 “it shall be a defence for any person to prove that he took all reasonable steps and exercised all due diligence to avoid the commission of that offence”.
The onus is on the User to specify a safe level of performance, and also check on receipt, that the equipment has been manufactured and supplied to their specification.
EVCE Installation
The purchaser / end user is responsible for contracting companies/staff with the necessary skills to carry out the work safely and to recognised level of competence (see HSE guidance INDG345). Currently there is no specific guidance within IET Wiring Regulations relating to EVCE installation, refer to the IET’s Code of Practice for EVCE with reference to IET Regulations where appropriate. Copies of documentation listed in the Code of Practice should be obtained and kept as a record of the work being completed safely and to specification before the installer leaves site. – Probably the minimum documentation requirements along with training, test and maintenance records for the “Duty Holder” to demonstrate due diligence under Regulation 29 (EWR).
Guidance
Please see below for a list of some of the independent guidance available relating to EVCE selection and installation. For specification applications or questions relating to the application of RCDs, specialist manufactures such as Doepke offer full technical help and support in the UK.
Chaz Andrews – Technical Manager, Doepke UK Ltd
[1] For an explanation: Type AC, A and B RCCBs see www.doepke.co.uk/rcd
Reference documents:
Provision and use of Work Equipment Regulations 1998
Electricity at Work Regulations 1989
IEE Wiring Regulations / BS 7671 (2011)
IET Code of Practice for Electric Vehicle Charging Equipment Installation
OLEV Government ecar technical specification
BEAMA Electric Vehicle Infrastructure Project
