Price Display Board: LED Rate Card for Petrol Pumps

LED price display boards are ubiquitous at petrol pumps, jewellery shops, money exchanges, and commodity markets across India. These bright, easily updatable displays show current prices that can be changed remotely without climbing a ladder. This guide covers building a professional LED price board suitable for outdoor commercial use.

Where LED Price Displays Are Used

• Petrol pumps: Fuel prices displayed on large format boards
• Jewellery shops: Gold and silver rate displays updated daily
• Money exchanges: Currency exchange rates
• Restaurants: Digital menu boards with daily specials
• Agricultural markets (mandis): Commodity prices

Display Technology Options

• Seven-segment LED (large format): Brightest, most readable for outdoor use. Best for numeric-only price display.
• Dot matrix LED: Can show text labels alongside numbers. Good for multi-line rate cards.
• HUB75 LED panel: Full colour, can show logos and graphics. Most expensive but most versatile.

Building a Static Price Display

For a petrol pump style display:

• Use 3-4 inch seven-segment displays for each price line
• 3 digits + decimal point for prices (e.g., 105.65)
• Multiple rows for different fuel types (petrol, diesel, CNG)
• LED labels (PETROL, DIESEL) above each price row

Remote Update via Bluetooth or WiFi

• Bluetooth (HC-05): Simple. Stand nearby and update from phone app. Range 10 metres.
• WiFi (ESP32): Update from anywhere on the same network. Add auto-fetch from oil company websites.
• GSM (SIM800L): Update via SMS from anywhere in India. No WiFi needed. Best for remote locations.

Outdoor Visibility and Brightness

• Outdoor displays must compete with direct sunlight
• Use super-bright LEDs (5000+ mcd) for daylight readability
• Add a sun-shade hood that protrudes 10-15 cm above the display
• Automatic brightness adjustment: full power during day, 30% at night to prevent glare
• Red or amber LEDs have better sunlight visibility than white or blue

Regulatory Considerations in India

• Petrol pump price displays must follow guidelines from the petroleum ministry
• Prices must be clearly visible from the road approach
• Minimum digit height varies by state — check local regulations
• Both unit price and effective date should be displayed

Power Backup for 24/7 Operation

• Use a 12V UPS or battery backup to maintain display during power cuts
• A small 12V 7Ah sealed lead-acid battery provides 4-8 hours of backup
• Solar panel option for locations with unreliable power

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