LED Indicator for Emergency Lamp. Start Up Project 39


charge-indicator-2-aMost of the low cost LED Emergency lamps do not have LED indicators to show charging and load on conditions. This simple circuit solves the problem. It can be hooked in the Emergency lamp. A Green LED lights when the charging is going on and turns off when the charger is disconnected or power fails. It gives a good indication that current is flowing to the battery. A Red LED lights when the load turns on. It also indicates that charging process stopped.
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Battery Protector for Emergency Lamp


Emergency lamps do not have a facility to prevent the deep discharge of battery if the lamp remains on during day time. The fluorescent lamp filament also damages if it is glowing in low battery voltage. This causes blackening of the filament side that indicates the damaged filament. So we have to switch off the lamp in the morning and switch it on again in the evening. By adding this circuit in the emergency lamp, you can reduce the job of daily switching. This circuit offers two advantages

1. It prevents unnecessary discharge of battery during daytime
2. It charges the battery only during night. This save energy and prevents overcharging of the battery.

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Battery Protector for Emergency Lamp.Utility Circuits 1


Emergency lamps do not have a facility to prevent the deep discharge of battery if the lamp remains on during day time. The fluorescent lamp filament also damages if it is glowing in low battery voltage. This causes blackening of the filament side that indicates the damaged filament. So we have to switch off the lamp in the morning and switch it on again in the evening. By adding this circuit in the emergency lamp, you can reduce the job of daily switching. This circuit offers two advantages

1. It prevents unnecessary discharge of battery during daytime
2. It charges the battery only during night. This save energy and prevents overcharging of the battery.

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Why Emergency Lamp is not doing well? Fact File 18


It is not its fault! But ours. We search for the emergency lamp only when power fails frequently. Otherwise it will be a dust depositor somewhere. To make the emergency lamp in good condition, proper care is needed. The emergency lamp battery is SMF (Sealed Maintenance Free) type and need not require water topping and can be placed in any position. It is rated 6 volts @ 4.5 Ah backup current.

 

The electrolyte of most SMF battery is a gel of Sulphuric acid mixed with Silica fume which makes the resulting mass gel like and immobile. This gel electrolyte reduces the electrolyte evaporation, spillage etc. One important feature of Gel battery is that the lead plates contain Calcium instead of Antimony to reduce water loss. Because of the presence of calcium, the gel battery charges very slowly compared to other batteries. Another important feature is its thermal sensitivity so the battery is vulnerable to thermal run away due to abusive charging. Over charging leads to its premature failure.

The Emergency lamp battery requires equal charge and discharge cycle. That is, it should be charged and discharged daily or once in two days. If it is always plugged in for charging, overcharging occurs leading to its permanent damage. If the battery is kept without charging for few days, self discharge takes place and the battery develops Memory Effect so that it will not charge fully. Deep discharge is another problem that can affect battery life. When the emergency lamp is kept switched on till it completely shut down, two adverse effects happen. The battery will not charge fully in recharging and the ends of tubes turn black due to filament damage. So it is better to switch off the lamp, when its light intensity drops.
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Battery monitor


Most of the Emergency lamps do not have low battery indicator which is essential to indicate the deep discharge of battery. So if the Emergency lamp is switched on continuously, battery will discharge deeply and causes 2 problems. 1. Ends of the fluorescent tube will turns black and fails. 2. If the battery is discharged fully, it may develop memory effect and will not accept full charge. To avoid these problems, the battery should not be allowed to discharge below its 50% efficiency. This simple add on circuit will give a visual indication when the battery enters in to the deep discharge stage.

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Battery Protector for Emergency Lamp


Emergency lamps do not have a facility to prevent the deep discharge of battery if the lamp remains on during day time. The fluorescent lamp filament also damages if it is glowing in low battery voltage. This causes blackening of the filament side that indicates the damaged filament. So we have to switch off the lamp in the morning and switch it on again in the evening. By adding this circuit in the emergency lamp, you can reduce the job of daily switching. This circuit offers two advantages

1. It prevents unnecessary discharge of battery during daytime
2. It charges the battery only during night. This save energy and prevents overcharging of the battery.

Continue reading