The multi-hour power backup solution using an Inverter and accompanying battery offers very high stability and durability; many customers have used our solution running 24/24h.
INVERTER: Converter that converts 12V DC power from the battery into 220V AC power. The product is used in many fields: Residential, power, telecommunications...
Battery: 12V sealed lead-acid battery, maintenance-free, lifespan of 5 to 20 years.
Normally, the uninterruptible power supply (UPS) standard models from manufacturers can only back up power for 23 minutes, enough time to save data and shut down the system. However, there are many needs that require continuous 24/7 operation without interruption, such as: data centers, banks, hospitals, Internet servers... standard UPS units cannot meet these needs, so more extensive backup power solutions are required, up to 8 hours or even 24 hours.
A solution combining an Inverter and automatic battery charger will provide customers with a way to ensure safe power supply and data safety, with backup time of several hours, from 1 to 24 hours (as specifically required).
Power outages disrupt the production and business operations of enterprises or affect the health and daily life of the people. When a power outage occurs, there are many suitable solutions to choose from depending on each customer's specific requirements, such as using a generator or using a UPS system, inverter, and battery to continue operating necessary electrical devices. However, each solution has its own advantages and disadvantages and is used for different purposes.
I. WHAT IS A POWER INVERTER
- The inverter (Inverter) is an uninterrupted, continuous power source. The device functions to convert power from direct current (battery) to alternating current with a very small conversion time measured in ms (milliseconds) or approximately zero (similar to Online UPS) in the event the main power source is lost.
- The backup time of the inverter depends on factors such as: battery capacity and the battery voltage connected to the Inverter. Higher battery voltage (i.e., more batteries connected to the system) results in a longer backup time and greater load capacity.
II. INPUT AND OUTPUT PARAMETERS OF THE POWER INVERTER
- Users should pay attention to the following parameters of the Inverter to invest and use it appropriately:
1. Output power: measured in VA or W (converted as 1W = 60% * 1VA).
- Use a power rating appropriate to the backup load. For example, for a total backup load of 500W, an inverter of about 1000W would be suitable.
2. AC input voltage of the inverter:
- Single-phase or 3-phase, voltage 220VAC/phase.
3. DC input voltage - Battery voltage: 12V - 1 battery, 24V - 2 batteries, .....
- To ensure stable output power, standard inverters typically require an input voltage of 24VDC for power ratings of 800W or higher. 12V should only be used for smaller power ratings of 600W or below.
- The higher the power, the correspondingly higher the input battery voltage required, such as: 24VDC, 36VDC 48VDC, 96VDC. When the input battery voltage is sufficient, the output will be stable, conversion efficiency will be high - meaning low losses - and the battery will have a longer service life.
- Inverter manufacturers recommend not using inverters with a lower-than-normal input battery voltage that output high power. That is merely a cost-saving manufacturing measure.
III. INVERTER SYSTEM COMBINED WITH BATTERY:
Overview:
Very low noise, very high voltage stability, fully automatic switching capable of operating 24/24 hours; when power is lost, the system automatically switches to backup power mode without any cost or operating labor.
The battery used is a fully sealed, maintenance-free dry battery with a very long lifespan of 5 to 15 years. This product is regarded as environmentally friendly and is therefore encouraged for use worldwide.
Because of its high voltage stability and uninterrupted continuous power supply (switching time 0 ms), it is often used for: offices, production facilities or households with equipment that needs to run continuously for data storage and processing, which would be interrupted if using a generator due to the startup time required.
Operating costs are very low and negligible; when grid power is normal, the system automatically charges the battery, and when power is lost, the system automatically uses the energy stored in the battery, converting it into AC power to supply the equipment in use.
The system offers many power capacity levels for customers to choose from, suitable for usage needs such as offices or households, as well as budget constraints.
Function:
Automatic switchover to backup power function. This function works like an automatic switch: it automatically switches to backup mode when there is a power outage and works as an electronic voltage stabilizer when power is available.
Battery for inverters: You should choose a sealed dry battery. The battery and the inverter must be compatible in terms of power usage. Inverters are typically designed with a standard charging current of about 15A for externally connected batteries. Therefore, you should only use batteries with a capacity of 200Ah or less, typically 100Ah. The number of batteries for the inverter depends on the power of each inverter. However, as mentioned above, for inverters of 800W or more, it is best to use 2 x 12V batteries.
Operating time of the inverter: Depends on the battery used and the charging current for the battery: For common inverters currently on the market, the maximum input battery voltage is 24V (2 batteries) for a power of 2000W or less, with a battery charging current limited to about 15A. Therefore, the backup battery capacity is usually around: 24V * 100Ah * 0.7 = 1680W.h (with a 12V/100Ah battery), so to extend usage time, users must use power sparingly, turning off unnecessary devices or loads. Example: If a total power of 100W is used at once, the maximum usage time will be 1680W.h/100W = 16.8 (h - hours).
IV. STRUCTURE AND OPERATION:
Schematic diagram of a common inverter.
A: Smart four-stage battery charger. Automatically adjusts the charging current
B: externally mounted sealed battery, suitable capacity.
C: Inverter that converts DC voltage into 220V, 50Hz AC voltage.
D: Electronic voltage stabilizer, regulating voltage within the range of 135VAC - 280VAC.
E: Solid-state electronic lock
- Solid line: Grid power mode
- Dashed line: Backup power mode
Operation:
1. When grid power is available:
- The current will flow along the solid arrow. Grid power will directly supply the load through an electronic voltage stabilizer (which stabilizes the grid voltage from 135-280V), with the output voltage being 220V supplied to the load.
- At the same time, the smart battery charger automatically charges the battery
2. When grid power is lost:
- The E lock will immediately automatically switch to the position of drawing power from the battery.
V. ADVANTAGES AND DISADVANTAGES OF POWER INVERTERS USING SEALED DRY BATTERIES:
Advantages:
In general, a local, small-to-medium-scale backup solution using sealed dry batteries with an inverter is truly an excellent choice for homes and offices, thanks to its outstanding advantages such as: compact and easy to use, even for the elderly and children. It is quiet and pollution-free, making it suitable for indoor use. And the output voltage of pure sine wave inverters is especially good for electrical and electronic equipment, helping to extend equipment lifespan (better than the grid power currently in use).
Extremely low operating cost (only about 3,400 VND/h to charge the battery, while a generator costs about 19,000-21,000 VND/h). Moreover, the system requires almost no maintenance. The long battery lifespan means lower total long-term investment cost.
This system is suitable for households or small and medium-sized offices, data servers, web servers, mail servers, network systems, wireless systems, surveillance camera systems, and other important systems requiring power supply, etc., with power requirements that are not too large
Disadvantages:
The initial investment cost is usually higher than a generator for capacities of 3000W or more.
VI. CALCULATING BACKUP TIME:
Backup time is calculated using the following formula:
T = ( Uaq x Q x 0,7 )/P
Where:
T: backup time.
Uaq: battery voltage (V)
Q: battery capacity (Ah)
0.7: Discharge coefficient.
P: backup load power.
Example: a household loses power and uses one 20W compact light bulb + one 60W electric fan. In that case, the backup time for a Santax 800W inverter using two 12V/100Ah batteries is calculated as follows:
T = (12 x 100 x 0.7) / (20+60) = 10.5 hours.
- DC voltage from the battery is converted through the inverter (C) into 220VAC, 50Hz to supply the load.
LISATECH provides genuine elevator equipment, components, and power supply equipment at the lowest prices. View product information frequency converter/inverter, battery, uninterruptible power supply (UPS)
LISA CONTROL TECHNOLOGY CO., LTD
Tel/Fax: +84 24 7309 9997
Address (Office): No. 10 LK10, Ha Tri Service Land Area, Ha Cau Ward, Ha Dong District, Hanoi City
Website: www.lisatech.vn
