We make a powerful uninterruptible power supply based on a standard UPS by connecting two KAMAZ batteries to it. We also do automatic ventilation when switching to autonomous mode.
This is the reality that Russian power grids force consumers themselves to care about the stability of the electricity they receive. In our case, it is necessary to solve two important problems: a large voltage drop (typical of the hot/cold season, when air conditioners/electric heaters are turned on) and a complete power outage (“knocking out” of machines, accidents at a substation, etc.).
If the first problem is easily solved by installing an autotransformer, which makes it possible to obtain a stable voltage of 220 volts at the output, then the second requires the organization of an uninterruptible power supply system designed for a long period of autonomous operation.
You can organize uninterrupted supply of a country house or garage by upgrading computer systems. After two years of operation, the internal batteries in any UPS degrade. Uninterruptible power supplies with non-working batteries have been repeatedly observed on the radio market at a symbolic price of 1000 rubles.
For long battery life, an uninterruptible power supply must be connected to high-capacity batteries. The best option would be starter batteries from KAMAZ vehicles - 140 Ah. Since most powerful uninterruptible power supplies use batteries with a total voltage of 24 volts, we need a pair of batteries connected in series. The duration of the autonomous power supply will depend on the condition of your batteries.
First of all, we take out and throw away the faulty battery. For the convenience of connecting an external high-capacity battery, we need to make contact clamps (preferably red and black, indicating plus and minus, respectively). To do this, we make two holes on the front panel of the uninterruptible power supply, fix the contact clips and solder the wires to them that went to the internal battery.
Long-term operation in the state of converting battery energy into a voltage of 220 volts is accompanied by large heating. To prevent premature failure, it was decided to install two conventional fans measuring 80x80x25 mm on the ventilation grille.
The fans are connected in series. To start the fans in conversion mode, we use an LED, which indicates the operation of the uninterruptible battery power supply. We solder the leads of the LED to the windings of a small relay with wires. We solder a wire from the incoming positive of our battery to one of the relay contacts. The second is a free red fan wire. We solder the free black wire of the fan to the incoming negative of the battery.
All! Now, when the uninterruptible power supply switches to battery mode, the cooling will automatically turn on.
Recently, very often people come to me with a request to provide instructions for converting a UPS (UPS) into a car voltage converter from 12 to 220 volts, and in this article I will try to explain how this can be implemented.
In fact, the UPS uninterruptible power supply can be used in a car as a voltage converter without any modifications, since the UPS itself is an inverter, which is designed to receive 220 Volts from a built-in 12 Volt lead battery.
In particular, the UPS uses lead batteries with a capacity of 7 or 10 Amp hours; in some powerful uninterruptible power supplies you can find two or even 4 similar batteries, which are connected in parallel to increase the capacity and battery life.
To remake the uninterruptible power supply, you first need to disassemble and remove the built-in battery. The power buses that are connected to the batteries must be removed from under the housing. It is advisable to use wires with an effective cross-section of 12 sq. mm. In many uninterruptible power supply systems, the housings are made of plastic, so you can simply drill the housing and remove the wires. It is advisable to connect the uninterruptible power supply directly to the car battery - the plus from the uninterruptible power supply to the plus of the battery, and the minus, respectively, to the minus.
What can you connect to a UPS?
First of all, pay attention to the power of the uninterruptible power supply. Cheap Chinese uninterruptible power supplies with a price of no more than 2000 rubles provide a relatively low output power. In my practice, I repaired power supply units from 300 to 1100 watts, but ideally they did not provide the declared power. For example, a Chinese 650-watt uninterruptible power supply could not handle a real load of 300 watts. It is necessary to test the power of an uninterruptible power supply specifically for passive loads - heaters, incandescent lamps, etc.
Another drawback is the shape of the output voltage, which differs from the mains sine wave. Almost all uninterruptible power supplies have a modified sinusoidal output. This form of voltage is not the best option, but it is possible to power motors and other loads, although I do not recommend connecting mains transformers and asynchronous motors to the UPS for a long time.
Large size and weight can also be considered a disadvantage, taking into account the fact that modern automotive voltage converters using pulse circuits have a much smaller weight and size than uninterruptible power supplies.
But nevertheless, if you need a pretty good, cheap inverter for use in field conditions, a UPS can be considered the best option and, in addition, uninterruptible power supplies have protection against overload and short circuits at the output.
Many PC users have old UPSs that have expired. A common cause of disability is battery failure. Since replacing with new batteries is unprofitable, and sometimes simply impossible due to the lack of analogues, these devices are simply lying around idle or thrown into the trash.
But you can give a second life to the UPS by making it a very useful device - an inverter that converts 12 in the car’s on-board network into the 220 V required for some devices. Despite the fact that the factory version of the inverter will cost a lot of money, this way you will save money and make the right thing out of trash.
So, the first thing to do is remove the old, leaking batteries. They can be easily dismantled by removing the bottom cover and disconnecting the power wires. If there are traces of leaked electrolyte, clean the case from oxidation crystals.
This operation will eliminate further acid leakage and will also significantly lighten the weight of the apparatus.
Uninterruptible power supplies differ in design, but their operating principle is the same - converting 12 V to 220 V. That is, each model contains a board with an electronic voltage converter. That's what we need. But there is one condition: it must be working.
Since the devices that will be connected to this device have a standard 220 V plug, it is necessary to install a regular household socket for hidden wiring on the side or rear panel. It is to this that we solder the output wires from the 220 V converter, which previously fit into special three-arm plugs on the back panel of the UPS.
In the first and second cases, the wires are soldered to those that went to the UPS battery. It is very important to maintain the polarity of the connection. The red wire is positive and the black wire is negative.
Both in the car network and in the UPS, these colors must match. It is best, of course, to check the polarity with a multimeter to be sure.
This connection scheme provides for immediate operation of the device when it is connected. If you want to turn it on via a toggle switch or machine, then simply break the “plus” in the wire coming from the car’s battery and connect one wire to the input and the other to the output of the machine attached to the UPS housing. This cuts off the power to the inverter when necessary.
It should be understood that such a device will not produce much power. Usually. it is no more than 150 W, but this is quite enough to connect a small TV, laptop and other low-current equipment.
Why is the car battery not charging from the charger?
Often in kulak households there is a working uninterruptible power supply (UPS) lying around idle with a dead battery. I propose to make it a 220 volt voltage source for the car. The design of the UPS may be different, but the principle is the same.
1. We disassemble the UPS, throw out the dead battery, bite off the terminals from it, and clean the ends.
2. Find the connector through which the UPS was connected to the 220 V network. In my version, the bottom right. We use it to connect to the on-board 12 V power system.
In my version, it is connected to the board via a connector, we bite it off. If there is no connector, simply bite the wires off the board and strip the ends.
3. Connect the wires going to the battery with the wires from the connector on the rear panel. The wires are thick, you will need a powerful soldering iron. We do not isolate the soldering points yet for later ringing.
4. Find the cigarette lighter socket and a regular computer cord (in my version it doesn’t have a plug). If you are not planning to use the inverter on the go in the car, I strongly recommend using alligator clips instead of the cigarette lighter socket and connecting the device directly to the battery.
We solder the cigarette lighter socket (clamps), observing the polarity (red is “plus”, black is “minus”), and isolate the soldering points.
5. An important point - so that the device does not scream like a robbed Jew, it is necessary to exclude the internal speaker.
I felt lazy about removing the board and unsoldering it for this purpose - I just tore off the speaker with pliers)))
In my version, I had to fix the transformer in the guides; for this, the discount card of the Astor chain, which died untimely in the abyss of the market, was ideal)))
6. Assemble the device body. All that remains is to attach standard sockets. There are UPSs that have them built into their design. I was unlucky; I had to destroy the carrier and the cord for connecting to the UPS.
Everyone is probably familiar with the situation when, when changing equipment to a newer one, you don’t know what to do with the old one, which has already become obsolete, but quite good so far. If there is no need to use the old computer for its intended purpose, then you can come up with new purposes for its components. For this, it will be useful to know what can be made from a UPS for a computer.
An old uninterruptible power supply can make a lot of devices in a hurry. Among other things, among them should be especially note useful in everyday life:
To make a charger from an old uninterruptible power supply, you need to proceed as follows:
Voltage calibration will be carried out with an improvised regulator within 0-15 volts.
You will have to control the charge level according to the indicator or using a voltmeter.A transformer without a battery will make a working inverter for a car. The assembly process will proceed according to the following scheme:
Read also: Review of UPS batteries for computers and their charging
A computer UPS is also suitable for a gas boiler. Conversion process should be done as follows:
A failed uninterruptible power supply Can be adapted to a 12 volt source. This is done very simply. First, you will need to connect an outlet to the UPS cord. To do this, one end is initially cut off from it. After performing this procedure using an uninterruptible power supply You can now charge your phone. By further simple transformations described above, you can increase the power of your homemade device (see the part about the inverter).
