Timers and Contactors

Timers and contactors for grow lights

A cheap mechanical timer will weld its contacts shut within a few weeks under an HPS or CDM load — the current spike when a 600W+ ballast switches on is enough to arc and fuse cheap contacts closed, leaving your light running 24 hours a day (or not switching on at all). A heavy-duty timer or contactor is built to handle that switching load properly.

For a single light, our 24hr Digital Timer or Heavy Duty Timer switches the load directly and copes with HPS and CDM ballasts without arcing. Running two or more lights from one circuit, step up to a contactor — the Eco Technics Power Star or Loadstar Timer Contactor (2, 4, 6 or 8-way) uses the timer only to trigger a relay, so the timer itself never carries the full lighting load. An MDF contactor board gives you a tidy pre-wired panel if you're running a multi-light room.

Sizing to your setup

One heavy-duty timer per light is the safe minimum; once you're past two or three lights on a circuit, a contactor is worth the extra cost to protect your timer and your wiring. Pair with our ballasts and hangers to finish the light rig, and see the grow tent setup guide for standard veg and flower light hours.

Free UK delivery over £50, next-day available. Call 020 3488 0419 if you're not sure whether you need a timer or a contactor.