This is a 48 Led solar / AC rechargeable emergency light. Fully recharged battery works 9 hrs with 24 led's and 4.5 hrs with 48 led's. A SPDT switch is used to select 24 and 48 led's. Deep discharge warning before 10 minutes of actual deep discharge is incorporated. Generally many emergency lights deep discharge cut-off stops suddenly. We don't know when it stops. That is why I made my circuit to beep at low voltage for 10 mins so that we can aware before stopping suddenly. We have to switch OFF manually after beeping within 10 mins. I used Solar panel for charging which is renewable energy.
Step 1: Parts Needed
- Emergency Light cabinet
- 6v 4.5ah rechargeable battery
- 12v white LED strip
- 12v 1amp transformer
- LM2596 DC stepdown module
- XL6009 DC stepup module
- Mains chord
- 12v solar panel
- ON/OFF rocker switch * 1
- 3pin SPDT switch * 1
- Green LED * 1
- DC jack male and female
- PCB plastic spacers * 6
- 1k resistor * 1
- 4007 diodes * 6
- 5402 diode * 1
- 1000mfd 25v * 1
- 5v buzzer * 1
- BC547 transissors * 2
- 33k resistors * 2
- 47k pot * 1
Step 2: Preparing the LED Panel
- Attach the LED strip to the mirror.
- Solder the wires to LED strip as shown in pictures.
- 1st and 4th strips are one set and 2nd and 3rd are one set.
Step 3: Setting the Voltages
- Solder a diode at step-down output in forward bias.
- Set the voltage 7.2v after the diode.
- Set the step-up voltage between 12v-14.2v.
Step 4: Deep Discharge Warning Circuit
Assemble the circuit. Adjust 47k preset so that buzzer beeps at 5.3v.
Step 5: Installing Electronics
- Place the electronics on base plate and make markings for the holes.
- Drill the holes and assemble the electronics.
Step 6: Preparing the Cabinet.
- Install the mains chord.
- Drill holes switches and DC female jack.
Step 7: Wiring
- Make diode bridge rectifier.
- solder 1 diode to SPDT switch.
- Start wiring all components as shown in pictures.
Step 8: Assembling
Assemble the light.
Step 9: Preparing the Solar Panel
Solder 5402 diode to +ve terminal in forward bias to protect the solar panel. Solder DC male jack to it.
Step 10: Testing
- Plug the AC and check for charging.
- Connect Solar panel and check.
Current consumption and battery backup time:
- 700ma for 48 LED's @ 12.4v and backup for 4.5 to 5hrs.
- 350ma for 24 LED's @ 12.4v and backup for 9 to 10hrs.
- 1.2amp for 48 LED's @ 14v and backup for 2 to 2.5hrs.
- 600ma for 24 LED's @ 14v and backup for 4 to 5hrs.