What is Deep Discharging?

A deep discharge occurs when the capacity of a battery has been exhausted. Battery cells have a set voltage at which they cease to function. This voltage is called the cut-off point. Exhausting deep causes 1.5 to 2 times as much electric discharge as the battery can support. As a result of over-discharging, the battery will have increased internal resistance, making charging difficult. The price tag on these batteries is high.

Depth of Discharge

According to the Depth of Discharge chart, the battery has used a percentage of its capacity as compared to its total capacity. If the batteries’ full capacity is 15kWh and you discharge 12kWh, that’s 96%. As a result, a deep discharge is something you should avoid. A deep cycle battery is a battery that is designed for deep discharge regularly. Power storage, UPS, traffic signals, and remote applications use these batteries.

Deep Discharge Protection Circuits

Identification of the battery’s cut-off voltage is necessary for deep discharge protection. A Zener diode in reverse bias condition will act as an open circuit when its cathode voltage falls below the breakdown voltage. It starts conduction when the cathode voltage is above its breakdown voltage. A switch disconnects the load from the battery, thus disconnecting the battery from the device. When the batteries reach the cut-off voltage level, we need to design a circuit to turn on a switch.

Protection Circuit for 12V Batteries

We will build a protection circuit to protect the load and battery from over-discharging, we will build a protection circuit. To adjust the resistance to achieve the desired range of operation, we’ll use a similar circuit but change the resistance. The diode is no longer conduction and there will be no base voltage, which effectively disconnects the battery from the load when the voltage is below 8V. We hope to use this circuit to protect the battery and the load from overcharging.

ICs Used for Over-Discharge Protection

Cs make our work easier when we are dealing with a complex circuit and have to regulate the power for the load. It is possible to replace several circuits with one integrated circuit. Integral circuits are capable of simultaneously monitoring and controlling power flow. Two integrated circuits can handle this application.

The LTC2960

A high voltage multi-cell battery monitor, the LTC2960 IC provides two input voltages. If the battery voltage is low, the RST pin in the IC signals a low voltage by going high. A user can provide the IC with either inverting or non-inverting inputs. Portable battery-powered equipment, batteries, and other systems commonly use this IC.

The LT1495

LT1495s are low-power op-amps that are capable of delivering very low supply currents. The supply can be fitted to 3V, 5V, or +- 15V. With a voltage range of 2.2V-36V, this device makes it possible to regulate a wide range of voltages. This IC offers several advantages over other protection circuits, including the fact that the circuit made by the IC uses less than 4.5miliamps of current. The device also protects batteries up to 18V.

How to Charge an Over-Discharged Battery

When a battery is overcharged, its internal resistance increases. Battery capacity can be lost twice as a result of this, so the battery has a hard time being recharged. When the voltage drops below 3.0V, severe damage occurs. Check the battery periodically for heat buildup and do not leave it unattended. In this situation, charges can be reduced. During puffing or overheating, it is impossible to restore the battery. Charges from batteries follow a similar pattern.

If you’re looking for the best place to get your power supplies, you’re in the right place! EP-Power aims to give you a total commitment to ensure the best quality and provide first-class products and services.

For inquiries, you may send us an email at: sales@edac.com.sg or give us a call at +6564547877.

Voltage Sags: What causes them?

Voltage sags are the most common cause of poor power quality. They are also the most costly. The more complex a plant is, the more voltage sags it is susceptible to, such as in-process controllers, PLCs, variable speed drives, and robots. A sag in voltage can cause relays and contactors in motor starters to fail, resulting in a shutdown.

Power quality is mainly affected by voltage sags. In addition to being the most expensive, they also have the longest lead times.

Complex industrial equipment, such as process controllers, PLCs, adjustable speed drives, and robots, is more sensitive to voltage sags as their complexity increases. As a result of voltage sags, motor starter relays and contactors break down, causing downtime.

What are voltage sags?

According to IEEE, voltage sag refers to a short-term reduction in voltage. At 60 Hz, the magnitude of the voltage reduction is between 10% and 90% of the normal root mean square voltage (RMS). By definition, a voltage sag event lasts less than 1 minute and more than 8 milliseconds, or a half cycle of 60-Hz electrical power. Undervoltage, transients, voltage unbalance among phases, voltage fluctuations, and electrical noise are also power quality issues affecting voltage amplitude and duration.

What causes voltage sags?

In both directions of an electric meter, power quality issues exist. It is typically the local utility that is blamed for voltage sags. The equipment within a plant is often to blame for voltage sag events. Switching operations are the most common human-created events. Human-created events, like switching operations, also constitute the majority of natural events. Even if the problem is caused by sags in power meters or other power quality issues, it’s difficult to determine the source of the issue.

Lightning

Wind

Trees falling onto power lines

Construction workers digging into buried cables

Squirrels and rodents

Equipment failures

Traffic accidents.

During voltage sag, there can be a difference in individual phase voltages and an accompanying phase-angle shift. The most common cause of sags is a single-line-to-ground fault (SLGF). Double and three-phase symmetrical faults are rare, occurring less than 20% of the time. Users beyond a 100-mile radius of the causing event can be affected by voltage sag on the grid. In some cases, a large motor can also cause voltage sags within the plant.

Detecting voltage sags

Monitoring power quality can detect voltage fluctuations, surges, interruptions, and other issues related to power quality. Power is measured as it enters a facility and compared with accepted standards. Systems that provide web-enabled power monitoring provide information on total harmonic distortion (THD), voltage, power factor, current demand, voltage unbalance, voltage sag, voltage swell, and alarms for multiple locations. Using one browser, a company in central Tennessee can monitor its facilities in Mexico, Canada, and across the country.

Simulation devices

Typically, the utility is responsible for sag, Undervoltage, and interruption events that occur outside the plant. Contacting the utility should be made when power quality problems occur, but when they occur within the plant, plant personnel should determine the cause. This problem may be resolved by providing more power, lowering the voltage drop, and using a soft-starting method. Several industrial devices can be easily tested for sensitivity using the sag generation apparatus.

Voltage sag reduction

Uninterruptible power supplies (UPS), constant voltage transformers (CVT), and solid-state sag correction devices are common power line conditioning technologies. The location of a machine affects its voltage sag sensitivity. Increasing wire size can reduce voltage drop when the wiring is to blame. The plant service entrance can often be used as an entry point for sag correction devices, such as on the control panel, at the machine level, or at the bus level. During voltage drops, momentary power blackouts, and extended power outages, UPS devices provide protection.

Power quality: A relationship-based challenge

Power quality and the ability to reduce the need for reliability and dependability must be understood in order to solve problems. Assuring PQ’s impact on operating facilities, and minimizing the costs of solving problems, requires an understanding of its relationships. Power quality problems are typically caused by the addition of new, more sensitive devices to an existing plant, not by a change in the power coming from the utility. A manufacturer knows the relationship between raw materials and the finished product. Why would a manufacturer losing $100,000 per year to scrap, misdirected labor, and lost production not spend half as much to stop these losses?

If you’re looking for the best place to get your power supplies, you’re in the right place! EP-Power together with TREK AND MONROEaims to give you a total commitment to ensure the best quality and provide first-class products and services.