Joining of Low Voltage Cable for Sub-Floor Ventilation Installations


In connecting Envirofan sub-floor ventilation systems various joining methods have been adopted.

The most common that is used is the use of male and female bullet connectors as illustrated in this article. This method is most likely the fastest method not necessarily the best method as the crimping process may fracture the wire inside the connector which does not allow the electricity to get through to the ventilation system. It is an adequate joining system but implementation must be done by using the right equipment. For example pliers should not be used as this does not deliver an effective crimp. There is a tool from the electronics store which is a ‘bullet connector crimping tool’. This delivers a double crimp to the connector which makes it doubly secure, however for the connector to stay steadfast, the cable which is a figure eight single strand needs the copper wire to be doubled over itself to create a thicker gauge, thereby when the crimper is engage on the red dot, despite it being a blue connector this will grip firmly making an effective joining process.

If the jointing method is made by grouping four strands of copper wire together then two strands positive with positive and negative with negative this is done by twisting the copper wires together which then will have a double thickness and the blue dot can used with the blue connector.

Electricians usually have ‘bp’ connectors and this is done by twisting copper wires together then inserting a insulated cap with grub screw over the cable. As an added insurance to keep corrosion and moisture out the connector, silicone can be used to fill the void in the connector.

Telephone technicians have ‘Scotch Lok’ connectors in their tool kit. The cable is inserted to connector and pliers are used to clamp down onto the cable. ‘Scotch Loks’ have been designed for telephony installations to keep moisture out of the cable and out of the connector.

In some installation soldering copper wires together has been used and the use of heat shrink insulation. As in the case of ‘bp’ connectors this is a positive joining process as the wires are in direct contact with each other. However this process takes considerable more time to install, but perhaps is the best.