Sangamo Round Pattern Astro Zone 3 Time Switch - 24 Hour 20A 3 Pin

The Sangamo round pattern astro zone 3 time switch is a 24-hour programmable controller with a 20A rating, designed to automate lighting circuits based on astronomical sunrise and sunset times for Zone 3 (North West England, North Wales). The unit features a circular dial with red hour markings from 0-24, brass contact terminals, and a 3-pin connection for live, neutral and switched live wiring.

Designed for outdoor lighting control in car parks, building exteriors, street lighting and security lighting across commercial and residential installations, the time switch adjusts switching times automatically throughout the year to match changing daylight hours without manual reprogramming. The Zone 3 setting corresponds to latitudes around Manchester, Liverpool, Chester and Blackpool, providing accurate sunrise and sunset timings for that geographic area.

The round pattern housing measures 104mm diameter and projects 134mm from the mounting surface when installed. A 100-hour battery reserve maintains programming during mains power interruptions, preventing the need to reset the schedule after short outages. The clear polycarbonate cover allows visual confirmation of the current time position and switching state, with brass terminals visible through the dial face. The unit is manufactured in the UK and carries the Sangamo brand, a specialist in time control products since 1918.

Product Specification Sheet

Product Manual

What is Zone 3 and which areas does it cover?

Zone 3 corresponds to the latitude band covering North West England and North Wales, including Manchester, Liverpool, Chester, Blackpool and surrounding areas. The time switch uses pre-programmed sunrise and sunset times specific to this geographic zone to control lighting automatically throughout the year.

How is the time switch wired?

The unit uses a 3-pin connection: live, neutral, and switched live. The switched live output energises the connected lighting circuit when the time switch is in the 'on' period according to the dial setting. Installation should be carried out by a qualified electrician in accordance with BS 7671 wiring regulations.

What happens during a power cut?

The 100-hour battery reserve maintains the time and programming for up to four days during mains power interruptions. When power is restored, the time switch resumes operation without needing to be reset, provided the outage was shorter than 100 hours.

Can the switching times be adjusted manually?

The unit operates on fixed astronomical times for Zone 3. To override or adjust switching times, you would need to rotate the dial face manually or select a different zone model that matches your required timing pattern. For fully manual control, consider a standard 24-hour time switch instead of an astro model.