Twilight Switch Digital 230V 1 Channel 972413 Hugo Muller

The Hugo Muller 972413 is a Twilight Switch Digital unit that turns lighting on and off based on how much daylight is actually present, rather than on a fixed clock time. A remote sensor reads ambient light and the control unit switches the load when the level crosses your set threshold, so lights follow sunset and sunrise as they shift through the year instead of needing seasonal adjustment.

The lux threshold is adjustable anywhere from 1 to 50,000 lux, which covers everything from a dim car park entrance to a bright open forecourt. Adjustable hysteresis of 0 to 50 percent and a delay time up to 59 minutes 59 seconds stop the output chattering when a cloud passes or a vehicle headlight hits the sensor.

Beyond pure light switching, the unit carries a full astronomical and clock program. You can run a daily or weekly schedule on top of the lux trigger, use Night OFF to kill lighting during a set overnight window, or set permanent switching by date for holidays and shutdowns. Thirty memory locations hold the program, and E2-PROM storage keeps it indefinitely through a power cut.

It mounts on standard 35mm din rail in a 45 by 35 by 58 mm housing with a high resolution LCD. The sensor unit is rated IP54 for outdoor use while the control unit sits at IP20 inside the board. Switching capacity is 16A resistive, with specific ratings for filament, halogen, fluorescent and LED loads listed in the technical data below.

Key Features

• Digital Twilight Switch

• DIN-rail mounting 35mm

• Switching capacity 16A

• Adjustable lux threshold 1 – 50,000 Lux

• Twilight switch with daily and weekly program

• Permanent switching by date

• Make / Brand: Hugo Muller

• Country of Origin: Germany

Product Manual

Technical Data

Common Applications

Street and car park lighting control, building facade and signage illumination, warehouse and yard flood lighting, villa and compound external lights, shop window displays that should follow daylight, and any installation where lighting should respond to actual light levels while still keeping a clock based schedule.

Related Twilight Switches

If you do not need the clock program and memory locations, the analogue models cost less for straightforward dusk to dawn switching. The 923500 analogue twilight switch comes with a wall mounting sensor, and the 923501 analogue twilight switch has a sensor for mounting within a housing. Both are 230V, 16A and mount on 17.5mm din rail.

See the full digital and analog twilight switches range, or browse digital and analog timers for time switches, astronomical timers and staircase timers.

Why Buy From Qahraba

Qahraba supplies electrical contractors, panel builders and procurement engineers across the UAE and worldwide. Order online or collect from our Dubai store. Call or WhatsApp +971 52 913 9543 for bulk pricing or technical help.

FAQ,s

What is a twilight switch?

It is a light sensitive control that switches a circuit based on ambient light level. A sensor reads daylight and the unit turns lighting on at dusk and off at dawn, following the seasons automatically.

What is the difference between a digital and an analogue twilight switch?

An analogue unit only responds to light level. The digital 972413 adds a clock, a daily and weekly program, permanent switching by date and 30 memory locations, so you can combine light sensing with scheduled control.

What does the lux threshold do?

It sets the light level at which the output switches. A range of 1 to 50,000 lux covers dim covered areas through to bright open ground, so the same unit suits very different sites.

Why does it have an adjustable hysteresis and delay?

To prevent the output flickering on and off. Hysteresis sets a gap between the on and off levels, and the delay makes the unit wait before acting, so passing clouds or headlights do not trigger switching.

Does the program survive a power cut?

Yes. Program security is unlimited through E2-PROM storage, and power back up runs about 10 years depending on lithium battery life.

Can the sensor be installed outdoors?

Yes. The sensor unit is rated IP54 to DIN EN 60529. The control unit is IP20 and belongs inside a distribution board or enclosure.