Trunking Systems
FAQs

Is halogen-free product available for Government, Child Care Centres and Schools?

Yes, a range of slotted trunking in 2M lengths with cable retainers. These products do not emit toxic or noxious fumes when exposed to flame.

Why do I need to use a Contactor?

A contactor is an electromechanical device typically used with a control circuit to enable the switching of a high current load. Wired in an interposing arrangement, a contactor can safeguard delicate control devices (e.g. time clocks, timers, and sensors) against premature failures often caused by direct switching of the load (e.g. lights, fans, heater… etc ). It is very important not to assume that the nominal AC1/AC7a current rating (eg 25A, 40A or 63A) is the contactor switching capacity for all types of load. For example, a 3P 25A contactor is not suitable for switching a typical 3ph 4kW motor (415V, 8.2A FLC) even though the 25A rating is higher than 8.2A. In this application, the suitable selection is a 3P 40A contactor. The reason for selecting a 3P 40A contactor is simply because every load has a different ‘load characteristic’. It is this load characteristic that can detrimentally affect a contactors switching capacity. Hence, depending on the application or specific load type (heating, motor or lighting), the contactors nominal current is derated accordingly to ensure optimum operation and reliability. Please refer to Contactor Technical Information when selecting a contactor.

What does AC1 (AC7a), AC3 (AC7b) mean?

Categorized in IEC 60947, AC1 (AC7a) and AC3 (AC7b) are ‘utilisation categories’ or switching capabilities based on load types: AC1 (AC7a) – non-inductive or slightly inductive loads, heaters, resistance furnaces.(power factor >0.8) AC3 (AC7b) - inductive loads, squirrel cage motors: (fans, vacuums, garage door and gate motors) starting, switching off motors during running.