Frequently Asked Questions

Below are some frequently asked questions regarding our courses and/or course content. If you require any further or more specific information, please do not hesitate to contact us.

Q. Does all electrical equipment for use in hazardous areas have to be submitted to a test house for certification?

A. No, electrical equipment in category 1, i.e. suitable for use in Zone 0,1 and 2 must be submitted to a test house (now known as a notified body) for EC Type Examination Certification. This also applies to category 2 equipment (i.e. suitable for use in Zone 1 and 2) . Equipment in category 3, i.e. suitable only for use in Zone 2 need only be subject to self certification by the manufacturer. For all electrical equipment for use in hazardous areas, the manufacturer must issue an EC Declaration of Conformity with his product.

Q. If an enclosure is marked II 2 GD and also EExd 11C T5 T100 IP 66, what is the meaning of the upper case and the lower case 'd's?

A. The upper case D is part of the ATEX labelling and indicates that the equipment is for use in areas where the explosion hazard is Dust (the G indicates Gas Hazard). The lower case d indicates the method of Ex protection, in this case flameproof (d from the German Druckefest Kapselung meaning pressure proof enclosure).

Q. I have an EExe electric motor which is labelled as T3, I understand this to mean that the temperature reached by any part of the motor will not be any greater than 200°C. Is this the case and do I need to consider ambient temperature effects?

A. This is true and if there is no ambient temperature range marked on the equipment then the T rating is based on a range of -20°C to +40°C. Any other range must be marked on the label.

Q. A flameproof EExd enclosure has a 32mm entry and we need to use it for a 20mm cable gland, is it permissible to use two reducers to achieve this?

A. No, EN 60079-1, the standard for flameproof equipment states that for any entry only one reducer can be used, also that reducers or adapters cannot be used at all with stopping plugs.