Power transformer » Transformer Articles » AC power isolation transformers and its uses

AC power isolation transformers and its uses

It would be interesting to know that the isolation transformers block the transmission of DC signals from one circuit to the other but at the same time allow AC signals to pass. For highly sensitive equipments like computers and other precision instruments, the isolation transformers with electrostatic shields are used to supply power. The specialty of isolation transformers is that it has symmetrical windings. These primary and secondary windings would decouple the two circuits. The basic idea is that the isolation transformers would give isolation, as the word suggests, rather than voltage transformation.

For operating sensitive equipments, AC power isolation transformers are the perfect choice since the sensitive ones are not able to tolerate today's higher line voltages. The AC isolation transformers posses certain general features like ventilated black steel case, rocker lighted on-off switch and fuse protected output. One of the most prominent features of the AC isolation transformers is its versatility.

There is another variety of isolation transformers called as the shielded isolation transformer. It would have all the features of the standard one and in addition they have a full metallic shielding. This would be either copper or aluminum which would be placed between the primary and secondary windings. Such transformers would be referred as electro-statically shielded isolation transformers. The electro static shield would be connected to earth ground to filter voltage spikes. The attenuation ratio of such shielded isolation transformers would be from 100 to 1. There would filtration for common mode noise too. The attenuation would be approximately 30 decibels. The isolation AC power supply would effectively filter both hot and neutral lines which is not possible with the traditional filters.

The isolation AC power supply unit is capable of isolating an amplifier from the source components. The unit would electrically isolate the amplifier or the offending component if any ground loop problems occur where there are multiple electrical paths for ground. As they provide protection for sensitive and critical equipment, the shielded AC isolation transformers are preferred over the standard isolation transformers. Most often all of the general purpose isolation transformers are shielded with no extra cost and this would come as a standard feature.

The design of AC isolation transformers would activate coupling between the two windings. There a grounded shield would be commonly interposed between the primary and secondary windings. The isolation transformer is used as a safety precaution in electronics testing, troubleshooting and servicing. The shock hazard is entirely contained within the device while using the isolation transformers.