29/04/2026
HOW TO CONNECT A PHOTOCELL WITH A CONTACTOR FOR AUTOMATIC SECURITY LIGHTS 💡🌙
Many people connect security lights direct to photocell… and after some months the photocell burns 😳
Why?
Because the photocell is not designed to carry heavy load alone.
✅ The professional way is to use a PHOTOCELL + CONTACTOR.
🔌 HOW IT WORKS:
The photocell acts like a sensor 👁️
During the day = photocell OFF
During the night = photocell ON
But instead of the photocell carrying all the current to many floodlights…
👉 it sends only a small signal to the contactor coil.
Then the contactor does the heavy switching of the lights safely.
That means:
✔ Photocell lasts longer
✔ Heavy load is protected
✔ Lights switch automatically
✔ Installation looks professional
🛠️ SIMPLE CONNECTION EXPLANATION:
✅ Phase from MCB goes to photocell LINE input
✅ Photocell LOAD output goes to A1 of contactor coil
✅ Neutral goes direct to photocell neutral and A2 of contactor coil
✅ Another phase supply enters contactor input terminals
✅ Output from contactor goes to all security lights
So…
🌞 Daytime → Photocell open → Contactor OFF → Lights OFF
🌙 Nighttime → Photocell closes → Contactor ON → Lights ON automatically
⚠️ COMMON MISTAKE ELECTRICIANS MAKE:
Connecting all floodlights direct on photocell without contactor.
This causes:
❌ Photocell overheating
❌ Frequent replacement
❌ Poor reliability
Always let the contactor carry the load 💯
🔥 A clean automatic lighting system shows the difference between a wireman and a professional electrical technician.
