Sparks Electrical News October 2016

CONTRACTORS’ CORNER

10

NEW GENERATION PROGRAMMABLE TIME SWITCH TECHNOLOGY FOR HEATING AND COOLING L egrand’s new generation of programmable time switch technology encompasses AlphaRex³ and MicroRex time switches for precise temperature control in domestic,

commercial and industrial environments. “Legrand’s Rex time switches, with analogue and digital dials, are ideally suited for OEMs and panel builders who can pre-programme the time switch during installation. At a later stage when the panel or product is connected to power, all the end-user has to do is set the real time,” says Marius Labuschagne, Legrand’s technical and solutions manager. “These programmable time switches ensure high clock precision,

optimum reliability, maximum safety and enhanced aesthetics. “In temperature control applications, these de- vices are used to switch an electric circuit on or off at selected times during a pre-programmed time period. These time switches also have an automat- ic return facility and a permanent forced switching on or off override control. “Typical applications for time switches in heat- ing and cooling installations include water heaters, air conditioners, heating and ventilation systems and swimming pool heaters.” AlphaRex³ programmable time switches have a user-friendly standardised text guided program- ming facility, with a high resolution digital display and backlight. There is a standard, single data key for all devices in this range to allow quick and easy transfer of programs to other time switches and for creating back-up copies. These time switches are available with standard and multiple functions, with a daily or weekly program facil- ity and a clock working reserve of six years. Programming with clock precision to the second is controlled directly on the time switch, or outside the distribution board using a PC and Legrand’s AlphaSoft programming software. Other features include an EEPROM memory, which prevents set- tings being lost and the facility to program the clock prior to despatch. Once the unit has been programmed, the information will remain installed even if the switch is not connected to power. The battery can be removed without having to uninstall the time switch from the distribution board. MicroRex time switches offer easy plug-and- play installation for daily and weekly program- ming. By simply setting the analogue switching dial during start up, the time is automatically set using the fast-run mode. In the event of a power failure, the time is automatically reset. MicroRex analogue and digital modules are 24- hour and seven-day time switches for DIN rail and wall mounting, with a 100-hour running reserve. These units have the capability for multiple pro- grams, which ensures optimum time setting flex- ibility. MicroRex time switches have an LED status indicator, precision clockwork of 0.2 s/day and are controlled by either a quartz or synchronous mo- tor. For increased safety and user convenience, there is an automatic and manual and advance and over-ride facilities. An analogue defrost switch is available for short periods of controlled defrosting. The timer can repeat one or two settable short programs within 24 hours and the defrosting time is from one to 60 minutes per contact. Other time switches in the Legrand range are designed for precise control in security instal- lations – for access points; electric fences and alarms – as well as for use in industrial installa- tions, including pump stations, filters and convey- ors. Legrand time switches are also used for the lighting of commercial boards and signage, as well as for street lighting. Time switches in agricultural applications are used for irrigation and sprinkler systems and for cyclical programs, such as animal feed systems.

Enquiries: +27 11 444 7971

SPARKS ELECTRICAL NEWS

OCTOBER 2016