
18
Modes 18 & 19: Base 0 Uni-polar Segmented
These modes are used for LTC monitoring
when the lowest tap number is
0
. There may be multiple neutral taps, which can be located
anywhere between the lowest and highest taps as long as they are grouped together in one
section. Mode 18 has a linear analog output that continuously varies with LTC shaft position.
Mode 19 has a stepped analog output that jumps with each tap change. To select this
operating mode, use the
OP 2, Func, MODE
command to change the value to
“18”
or
“19”
.
Figure 2.5 Base 0 Uni-polar Mode Analog Output
Programming Example:
A typical transformer Load Tap Changer application with taps numbered 0 to 16,
2 neutral taps, with 10.5
o
per tap, presently set on tap “9” would be programmed as follows:
OP 2 Operating mode = 19 OP 21 Degrees per tap = 10.500 OP 27 Present tap = 9
OP 20 Number of taps = 18
OP 22 Number of neutrals = 2
OP 28 Load present tap
OP 23 Neutral start tap = 0