Nowadays, efficient power consumption should be a part of any company’s operating strategy. Whether in the field of information technology or services industry, knowing how much electricity is being consumed is key to both future savings and increased productivity.
One of the essential pieces of equipment needed for this are current transformers, which are used to measure how powerful a current is passing through a wire. They work on the basis of producing a weaker current proportional to the higher voltage that is usually found in power cables; this makes it safer to measure the amount of power passing through it.
There are three general types as described in an article from Electronics Tutorials about the basics of current transformers:
- Wound current transformers – The transformers primary winding is physically connected in series with the conductor that carries the measured current flowing in the circuit. The magnitude of the secondary current is dependent on the turns ratio of the transformer.
- Toroidal current transformers – These do not contain a primary winding. Instead, the line that carries the current flowing in the network is threaded through a window or hole in the toroidal transformer. Some current transformers have a “split core” which allows it to be opened, installed, and closed, without disconnecting the circuit to which they are attached.
- Bar-type current transformers – This type of current transformer uses the actual cable or bus-bar of the main circuit as the primary winding, which is equivalent to a single turn. They are fully insulated from the high operating voltage of the system and are usually bolted to the current carrying device.
This provides a variety of choices among the available split core transformers and other types from Aim Dynamics. In the past, experts would have chosen solid core transformers for their inexpensiveness and their accuracy. However, the problem with them is that they have to be put in place at installation; if you want to install a solid core current transformer afterwards, you’ll have to turn off the main power and be ready to pull out some wires.
In contrast, a reliable split core current transformer would be able to be snapped on over a wire, with no need for screws or brackets. They can be added to an installation by placing control panels at important junctions in a system, so as to gather data. They aren’t as accurate as wound current transformers and have a higher price tag, but they are often the only options available for some situations like older facilities or the need for immediate power monitoring.
(Source: The Current Transformer, Electronics Tutorials)