Grow room electrical is the part people improvise and should not. A grow room pulls a serious continuous load, in a warm room, often with water nearby – it deserves properly rated kit rather than a daisy chain of kitchen extension leads.
Work out your load first
Add up everything that runs at once: fixture wattage, fan, filter, pumps, controllers. A 600W HPS with a ballast draws closer to 660W in practice. A UK 13A socket gives you roughly 3,000W total, and you should not be planning to sit anywhere near that ceiling on one circuit.
What you need
Timers. The single most important component in the room – it decides your photoperiod. A cheap mechanical timer that sticks will revert a flowering plant. See timers and contactors.
Contactors. Once you are switching more than one fixture, a plug timer is not rated for the surge. A contactor takes the switching load and the timer just tells it when. Non-negotiable above about 1,000W of lighting.
Properly rated extension leads – heavy duty, fully unwound. A coiled reel under load is a fire risk.
IEC leads and adaptors for fixtures and ballasts.
Surge protection for controllers and anything with a circuit board.
Basic safety, briefly
Keep every connection off the floor and away from run-off. Drip loops on every cable.
Never run a reel coiled. Unwind it fully.
Do not chain extension leads. One lead, one socket.
If you are unsure about the load on a circuit, get an electrician. This is the one area where guessing is genuinely dangerous.
We are a hydroponics shop in Croydon and we will tell you when your setup needs a contactor rather than selling you another timer. Discreet UK and European delivery, and excellent customer reviews on Trustpilot.
