P54x/EN ST/La4 Settings
(ST) 4-40
MiCOM P543, P544, P545, P546
ST
1.3.13 Residual overvoltage (neutral voltage displacement)
The NVD element within the MiCOM P54x is of two-stage design, each stage having
s MT
o
eparate voltage and time delay settings. Stage 1 may be set to operate on either an ID
r DT characteristic, whilst stage 2 may be set to DT only.
Setting range
Menu text Default setting
Min. Max.
Step size
VN>1 Function DT Disabled or DT or IDMT N/A
Setting for the tripping characteristic of the first stage residual overvoltage element.
VN>1 Voltage Set 5 V 1 V 80 V 1 V
Pick-up setting for the first stage residual overvoltage characteristic.
VN>1 Time Delay 5 s 0 s 100 s 0.01 s
Operating time delay setting for the first stage definite time residual overvoltage element.
VN>1 TMS 1 0.5 100 0.5
Setting for the time multiplier setting to adjust the operating time of the IDMT
characteristic.
The characteristic is defined as follows:
t = K / ( M – 1)
Where:
K = Time multiplier setting
t = Operating time in seconds
M = Derived residual voltage/relay setting voltage (VN> Voltage Set)
VN>1 tReset 0 s 0 s 100 s 0.01 s
Setting to determine the reset/release definite time for the first stage characteristic
VN>2 Status Disabled Disabled or Enabled N/A
Setting to enable or disable the second stage definite time residual overvoltage element.
VN>2 Voltage Set 10 V 1 V 80 V 1 V
Pick-up setting for the second stage residual overvoltage element.
VN>2 Time Delay 10 s 0 s 100 s 0.01 s
Operating time delay for the second stage residual overvoltage element.