Datasheet

14 GMC-I Messtechnik GmbH

4.4.4 AC Currents with (Clip-on) Current Transformers

Attention!

Prior to closing the primary circuit, verify that the secondary

circult is closed. If current transformers are operated in open

state on the secondary side, e.g. due to defective or not con-

nected leads, due to a blown fuse because of prior overload,

or due to a wrong position of the range switch (not on the cur-

rent range), dangerously high voltages can appear at the con-

nection terminals. Therefore, first check that the current circult

of the measuring instrument and the secondary winding of the

transformer which is connected to the instrument form an

uninterrupted measuring circuit. This can be done for all mea-

suring ranges by means of a resistance measurement as

described in chapter 4.6.

Clip-on current transformers allow for measurements of AC currents

without the need to interrupt the operating circuit. For the use of both

bushing type current transformers and clip-on current transformers the

maximum permissible operating voltage is the rated voltage of the cur-

rent transformer. Take into account the additional error in indication.

Ð Set the range switch to position A~.

I(A)