6
3. Measured accurately limit coefficient, Instrument security coefficient and symmetrical
short-circuit current multiples
4. The measured transient dimensioning coefficient, peak transient error and second time
constant
For different CT, different parameters should be set. Details as table 2.2
Table 2.2 CT parameter description
parameters
description
R-IEC
R-ANSI
TPY
M-IEC
M-AN
SI
PR PX TPS TPX TPZ
rated primary
current
Used to calculate
the ratio of actual
current accurately
√
√
√
√
√
√
√
√
rated burden Rated load of
plate, power factor
for 0.8 or 1
√
√
√
√
√
√
√
√
power factor
√
√
√
√
√
√
√
√
Rated
accurate limit
coefficient
alf
K
The provisions of
the plate, default
10,used to
calculate the limit
e.m.f. and their
corresponding
composite error
√
Rated
symmetric
short-circuit
current
coefficient
ssc
K
The provisions of
the plate, default
10,used to
calculate the peak
and their
corresponding
limits e.m.f
transient error
√
√
√
√
Primary time
constant
default :100ms
√
√
√
Second time
constant
default :3000ms
√
√
Duty cycle
C-t1-O or
C-t1-O-tfr-C-t2-O
，
default:C-t1-O
cycle
√
√
