Many car enthusiasts know what a car inverter is, which changes the voltage from 12 to 220 V. In fact, this is a real transformer. But there are also transformers of other work, which take 220 V at the input, and give to the consumer... all the same 220 V. Why are they needed? Let's figure it out.
Why do you need a 220/220 V transformer
Everything is very simple. Voltage “comes” to houses and apartments from a step-down substation or a nearby transformer that converts 6, 10 or more kV into more acceptable 380 V. It is enough to bring one phase to the dwelling from the low side of such a transformer and provide the network with a neutral wire - and you can use a household voltage of 220 V.
But even such a potential difference will remain dangerous for humans. Touching the phase wire will lead to a serious "blow", which can leave consequences for human health, and even life. To prevent this from happening, you should install an OSM 220/220 transformer in your switchboard.
Installation of this transformer has many advantages:
- The short-circuit current is reduced on the line.
- Hazardous ground potential is lost.
- Additional protection against sudden power surges.
Of course, all of the above points can be eliminated by installing elements such as voltage relays, RCDs, etc. But the transformer rather belongs to the group protection class - one device replaces many others, including the circuit grounding.
How to connect OSM 220/220
The input and output on the OSM 220/220 case are marked, since there should be no problems with connecting the transformer. It should only be remembered that the input "comes" a phase wire from the shield, with a voltage of 220 V. And from the transformer back to the shield "goes" a wire of the same section. It turns out that the OSM is an intermediate link and is mounted in the phase wire break.
Be aware that the wire after the transformer must go through a separate circuit breaker. This is necessary to protect the OCM in the event of a short circuit or prolonged heating of the conductors.
For OSM 220/220, a separate cabinet may also be required - this transformer, like all the others, buzzes during operation. In the cabinet, it should be properly insulated from any metal surfaces.
Is the installation of an isolation transformer helpful?
One transformer model OSM 220/220 replaces the ground loop, RCD and voltage relay. Even in the event of a short circuit, the wires do not heat up excessively, and the OSM simply “eats up” voltage drops, providing reliable protection for fragile household appliances, such as a computer.
But there is one catch. It will not be possible to put one transformer on the whole apartment at once - they simply do not produce such a high power. Therefore, you will have to take a few, which at a price may exceed the installation of additional switching elements in the switchboard. And yet, installing the OSM will save the user from installing grounding, which is considered a rather expensive process.