Built-in LDR light sensor switches the LED on at sunset and off at sunrise. No timers, no external photocells, no manual switching. IP-65 potted, surge-protected, made in India.
A dusk to dawn LED driver is a power supply with a built-in light sensor — usually a Light Dependent Resistor, or LDR — that switches the LED light on automatically when the ambient light drops at sunset, and switches it off again at sunrise. No external timer, no separate photocell box on the pole, no relay wiring. The sensor sits inside the driver housing itself.
For street lights, gate pillar lights, security floodlights and rural signage where someone manually switching the light each evening isn't practical, a dusk-to-dawn driver replaces the entire timer + relay setup with a single sealed component. The result: no scheduling mistakes during daylight-saving changes, no lights left on in the morning, lower running cost.
The encapsulated series spans 36W to 100W — SP-111LR (36W), SP-108LR (50W), SP-110LR (60W) and SP-109LR (100W) — plus the SP-107LR 50W open-frame version. All ship from our Sahibabad plant in Ghaziabad with a 2-year warranty.
Our most popular dusk-to-dawn driver for street lights, security floodlights and pole-mounted commercial fixtures. Constant-current output, IP-65 potted, handles voltage fluctuations from 120V to 300V AC.
Our highest-power dusk-to-dawn driver — for main-road street lights, high-mast fixtures and large floodlights. Three output ranges cover most 100W LED configurations. Same IP-65 potting and LDR sensor as the 50W.
| Model | Wattage | Output | Construction | Surge |
|---|---|---|---|---|
| SP-111LR | 36 W | 24-45V · 1A / 52-66V · 600mA | IP-65 potted | 6 kV |
| SP-108LR | 50 W | 24-45V · 1.5A / 52-66V · 800mA | IP-65 potted | 6 kV |
| SP-110LR | 60 W | 24-45V · 1.5A / 52-66V · 1A | IP-65 potted | 6 kV |
| SP-109LR | 100 W | 30-45V · 2.7A / 50-75V · 1.5A / 90-130V · 700mA | IP-65 potted | 6 kV |
| SP-107LR | 50 W | 24-45V · 1.4A / 52-66V · 800mA | Open frame (for sealed luminaires) | 4 kV |
All models: 120–300V AC operating range, PF >0.95, THD <10%, sustains 440V AC up to 4 hours, HV/LV cut-off with auto-reconnect. Surge tested per IEC 61000-4-5.
Municipal street lighting, residential colony lights, parking-lot floodlights. Auto-switching eliminates the need for a centralised timer or relay system.
Perimeter lighting, warehouse boundary lights, godown floodlights. Stays lit all night without anyone having to switch it on or off.
Residential gate posts, farmhouse entrance lights, semi-rural property markers. Set-and-forget — no daily switching needed.
Backlit signboards for shops and showrooms — auto-on at sunset means signage is always visible during business hours without manual operation.
Areas with unreliable manual switching or no on-site staff. Solar-powered installations pair with dusk-to-dawn drivers for fully autonomous operation.
Garden lights, garden-path lights, courtyard lights. Stays lit all night when needed, off during day for energy savings.
The LDR (Light Dependent Resistor) is a small photoresistor mounted on the driver PCB. Its resistance drops as ambient light increases — bright sunlight produces low resistance (a few kilo-ohms), darkness produces high resistance (megaohms).
The driver's internal logic reads this resistance continuously. When light drops below about 10 lux — typical late-twilight conditions — the driver enables LED output. When light rises above about 30 lux at sunrise, the driver cuts output. The gap between switch-on and switch-off thresholds (called hysteresis) prevents the light from flickering rapidly during cloudy transitions or when headlights pass.
Because the sensor is integrated into the driver, the entire control system is sealed inside the IP-65 potted housing. There are no external photocell wires to fail, no relay contacts to oxidise, and no separate timer to drift over the year as daylight hours change.
Designed and manufactured at our own plant in Sahibabad, Ghaziabad. In-house R&D team, no white-labelling. Local warranty support.
Designed for 120–300V AC input variation common in semi-urban and rural India. 6kV surge protection (IEC 61000-4-5) handles monsoon lightning transients on overhead distribution lines.
Need a different output voltage, current rating, surge level, or sensor threshold? OEM customisation available from 100-unit MOQ.
A LED driver with a built-in light sensor (LDR) that switches the light on automatically when ambient light drops at sunset, and off at sunrise. No external timer or photocell required.
The LDR needs to see ambient outdoor light to read correctly. The driver is best mounted where the LDR sensor (a small bead on the PCB) has line-of-sight to the sky or general daylight. In fixtures with translucent diffusers, mounting works fine. Inside a fully enclosed metal housing without any light entry, it won't switch correctly.
The standard threshold is calibrated to typical Indian dusk (around 10 lux). For OEM orders above 100 units, custom thresholds can be set — for example a brighter threshold so the light turns on earlier in monsoon overcast conditions.
Yes, as long as the LED load matches the driver's output spec. The SP-108LR (50W) drives 24–45V DC LED chains at 1.5A or 52–66V DC at 800mA. The SP-109LR (100W) offers three ranges: 30–45V at 2.7A, 50–75V at 1.5A, or 90–130V at 700mA. Match the LED to the driver — happy to advise based on your LED's forward voltage and current.
Dusk-to-dawn switches based on ambient light alone (always on at night, off in day). Motion sensor drivers dim or switch based on detected movement. Some advanced fixtures combine both — dusk-to-dawn enables the light, motion sensor brightens it when activity is detected. Ask us about combined options.
WhatsApp us at +91 82872 62090 or email sales@smoothpower.in. Mention the quantity, target wattage, and any custom requirements — we'll send pricing within one business day.