10 / 28
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