3.3 Definitions related to current ratings
3.3.201
rated primary current
value of the primary current on which the performance of the transformer is based
[SOURCE: IEC 60050-321:1986, 321-01-11, modified title, synonym and definition]
3.3.202
rated secondary current
value of the secondary current on which the performance of the transformer is based
[SOURCE: IEC 60050-321:1986, 321-01-15, modified title, synonym and definition]
3.3.203
rated short-time thermal current
maximum value of the primary current which a transformer will withstand for a specified short time without suffering harmful effects, the secondary winding being short-circuited
[SOURCE: IEC 60050-321:1986, 321-02-22]
3.3.204
rated dynamic current
maximum peak value of the primary current which a transformer will withstand, without being damaged electrically or mechanically by the resulting electromagnetic forces, the secondary winding being short-circuited
[SOURCE: IEC 60050-321:1986, 321-02-24]
3.3.205
rated continuous thermal current
value of the current which can be permitted to flow continuously in the primary winding, the secondary winding being connected to the rated burden, without the temperature rise exceeding the values specified
[SOURCE: IEC 60050-321:1986, 321-02-25]
3.3.206
rated primary short-circuit current
r.m.s. value of the a.c. component of a transient primary short-circuit current on which the accuracy performance of a current transformer is based
3.3.207
exciting current
r.m.s. value of the current taken by the secondary winding of a current transformer, when a sinusoidal voltage of rated frequency is applied to the secondary terminals, the primary and any other windings being open-circuited
[SOURCE: IEC 60050-321:1986, 321-02-32]
3.4 Definitions related to accuracy
3.4.3
ratio error
Definition 3.4.3 of IEC 61869-1:2007 is applicable with the addition
3.4.4
phase displacement
The definition 3.4.4 of IEC 61869-1:2007 is applicable with the addition of the following note:
Note 1 to entry: An explicative vector diagram is given in 2A.1.
3.4.201
rated resistive burden
rated value of the secondary connected resistive burden in ohms
3.4.202
secondary winding resistance
actual secondary winding d.c. resistance in ohms corrected to 75 ºC or such other temperature as may be specified
Note 1 to entry: Rct is an actual value. It shall not be confused with the upper limit for Rct, which can be specified otherwise.
3.4.203
composite error
under steady-state conditions, the r.m.s. value of the difference between
a) the instantaneous values of the primary current, and
b) the instantaneous values of the actual secondary current multiplied by the rated
transformation ratio,
the positive signs of the primary and secondary currents corresponding to the convention for terminal markings
[SOURCE: IEC 60050-321:1986, 321-02-26, modified note to entry]
3.4.204
rated instrument limit primary current
value of the minimum primary current at which the composite error of the measuring current transformer is equal to or greater than 10 %, the secondary burden being equal to the rated burden
[SOURCE: IEC 60050-321:1986, 321-02-27]
