Test Certificates
Our production facilities allow automated printing of test cetificates for individual current transformers, if requested.
Terminal Covers
Ring type current transformers can be provided with sealable terminal covers. Please specify on your order if required.
Burden
When choosing the VA of a current transformer, the burden of the instrument should be taken into account. For example, moving iron panel meters require a VA of less than 2.5 . Where possible the instrument is remote from the CT, the VA imposed by the length of the connection wires should be taken into consideration. The graph opposite outlines the effect of connection wire length on VA.
Multiple Primary Turns
The ratio of a current transformer can be reduced by passing more than one conductor turn through the centre of the CT. The ratio will therefore be the CT primary divided by the number of turns. For example, a 400/5A CT with 2 primary turns passed through the centre, will provide an actual ratio of 200/5A