A contactor is operated by means of a solenoid operation, whereby upon energisation of a coil (your signal), the solenoid will operate and the contacts will also operate.
You need to think of a contactor as a two state device, i.e. either energised or de-energised.
When you read that a...
110V supplies are used for control purposes in europe. you need a single phase 240V supply feeding a safety isolating transformer, with 55V live / 55V neutral, which is classed as safety ELV, which provides a reduced shock potential. This system is also used for construction works tools and...
The British standard BS 7671 requirements for electrical installations does not translate as a european harmonised standard (EN) due to the peculiarities between electrical supplies of british and other countries.
Andy
The reason for selecting an oil immersed transformer over a dry type is so that it may be installed externally without any additional weatherproof enclosure wheras dry types require a housing of some description.
