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Product at a glance

SIR021 is 30/60/120-minute timer and is part of the SIR range of simple push-button electronic timers, that saves energy by remembering to switch Off appliance when you might forget. Each press of the button cycles the timer through the available periods, as shown by indicator LEDs. The connected load is automatically switched Off at the end of the preset time, or it can be switched Off manually using the push button. Large energy savings are possible by adding this simple device to any electrical appliance, up to 3 kw (resistive). These units are perfect as boiler override or extension timers and can be used on panel heaters, immersion heaters, heated towel rails, and oil-filled radiators.


Electrical switching

Timer and scheduling to control any electrical appliance up to 3 kW, such as:
  • Immersion heaters
  • Panel heaters
  • Heated towel rails
  • Oil-filled radiators
  • Forced ventilation in conference rooms


  • Wiring is simple with easy access terminals


  • Choice of three models:
    • SIR020: 15/30/60-minute timer
    • SIR021: 15/30/60-minutetimer
    • SIR022: 2/4/6-hour timer
  • Switches loads up to 3 kW (resistive)
  • Flush or surface mounting
  • ‘Countdown’ LED indicator light
  • 7 years no quibbles warranty


Purpose of control Electronic timer (independently mounted)
Contact type Micro-disconnection
Contact rating 13 (3) A, 230 V AC
suitable for loads up to 3 kW (resistive)
Control action Type 2B
Software Class Class A
Operation time limitation Intermittent
Timing accuracy ±5%
Timer boost period SIR020: 15/30/60 minutes
SIR021: 30/60/120 minutes
SIR022: 2/4/6 hours
Dimensions (W x H x D) 85 mm x 85 mm x 19 mm (flush mount)
85 mm x 85 mm x 44 mm (surface mount)
Weight 0.2 kg (approx.)
Case material Flame-retardant thermoplastic
Ball pressure test temperature 75˚C
Mounting Single-gang surface mount/flush box, minimum depth 25 mm (UK)/35 mm (Continental Europe)
Impulse voltage rating Cat II 2500V
Enclosure protection IP30
Pollution Degree Degree 2
Operating temperature range 0˚C to +35˚C
Standards EN 60730-2-7