Mark Flanagan, the Technical Manager with Scolmore Group looks at some of the problems associated with inferior quality connector products, which don’t meet the required standards and therefore, represent a safety hazard.
Since Scolmore introduced the first-ever Flow Connector in 2007, it has proved a highly popular product and has continued to grow and develop the range. Inevitably this has led to a lot of copies of the product being brought to market. They may be cheaper, but in many cases, they are of inferior quality and don’t meet the relevant standards. Scolmore has heard reports that other manufacturers’ connectors can plug into their connectors. This may be the case but is not safe.
Connectors
Scolmore would like to draw attention to the inter-compatibility of connectors
Connectors are a method of joining one conductor to another and are capable of passing larger currents and voltages. A poor connection passing such currents can cause high resistance faults which could generate enough heat to degrade insulation which in turn can lead to a breakdown in the circuit and, in extreme cases, result in fire.
In light of this recent influx of inferior copies, Scolmore would like to draw attention to the inter-compatibility of connectors and look at some of the standards that installation couplers should be conforming to, as well as some of the associated dangers and risks.
Standard IEC EN 61535
Standard IEC EN 61535 relates to the installation of couplers intended for permanent connection in fixed installations.
Clause 9.1
It should be noted that unintended or improper connections include single-pole connection
Clause 9.1 - An installation coupler system shall be designed and constructed so that unintended or improper connection is prevented. It should be noted that unintended or improper connections include single-pole connections, except for earth-to-earth connections.
Compliance is checked by inspection and the following test. It shall not be possible to insert the installation male connector into the installation female connector resulting in a dangerous situation.
Configuration of engagement
Engagement of the installation male and installation female connector is attempted in any unintended configuration using a force of 80 N for installation couplers marked as 10A, 16A, 20A; or 120 N for installation couplers marked as 25A and 32A.
The force shall be applied on the same axis of the connection for one minute during which time the installation male and installation female connector contacts shall not engage.
Clause 9.2
Clause 9.2 - It shall not be possible, within a given installation coupler system, to engage an installation male connector with an installation female connector:
- With a different number of live poles; exceptions may be admitted for the installation of female connectors which are specially constructed to allow engagement with the installation of male connectors of a lower number of poles, provided that no dangerous situation can arise;
- Without earthing contact if the installation male connector is an installation male connector with earthing contact;
- With different phase to neutral voltage ratings or different rated currents.
Compliance is checked by the test according to 9.1.
Clause 9.3
Clause 9.3 - Installation couplers of different systems from the same manufacturer shall not be dangerously compatible. Compliance is checked by the test according to 9.1.
Clause 9.4
Scolmore's Flow connector is designed to prevent unintended or improper connection
Clause 9.4 - Installation couplers according to this standard shall not be compatible with systems specified in standard sheets of IEC 60309, IEC 60320, IEC 60906, and with the national household plug and socket-outlet systems of the country where the product is placed on the market.
Compliance is checked by manual test and in case of doubt by examination of drawings. Scolmore's unique Flow connector is designed to prevent unintended or improper connection.
The polarity of a connection
The incorrect polarity of connections could be considered unintended or improper connections and could result in a dangerous situation.
If the polarity of a connection is incorrect then the appliance/fixture connected, will either not work, resulting in time spent fault-finding, or, in some cases, appliance/fixtures can remain live, even if the power switch is turned off to them.
Clause 12 of the standard deals with Construction.
It shall only be possible to render the means of retention ineffective by a deliberate act
Clause 12.10 - Installation couplers shall be provided with retaining means which engage automatically when the installation coupler or cap is connected and which are capable of disengagement for disconnecting. It shall only be possible to render the means of retention ineffective by a deliberate act.
For installation couplers classified by 7.4.1 intended for installation in a readily accessible location, the means of disengagement shall only be made by the use of a key or tool.
Compliance test
The fully engaged installation coupler shall be subjected to a smooth axial traction force of 80 N for one minute, during which the retaining device shall be fully engaged. The installation coupler shall not loosen or become disconnected.
Should the installation coupler loosen, this may result in the earthing integrity of a circuit not being maintained. In the unfortunate event that something goes wrong - such as a short or fault with an appliance - it may be possible to expose someone to a serious shock hazard, as it may impair or prevent the operation of protective devices in the circuit.
Safety is critical
Scolmore has highlighted some of the standards that installation couplers should be conforming to. Safety is a critical market requirement and manufacturers must identify the required regulations and develop products that meet the required standards.
All of Scolmore's products are independently third-party verified to provide the reassurance and confidence that the products being sold or installed are safe and fit for the intended purpose. Not all manufacturers can say the same.
