master:dscd87 parametersPSCAD Dual Slope Current Differential Relay

Every parameter of the PSCAD Dual Slope Current Differential Relay (master:dscd87): 9 names, with the unit, the default and the meaning PSCAD gives each one. Copy a name into parameters().

What master:dscd87 is

Dual Slope Current Differential Relay, a component of PSCAD's Master Library, filed under protection.

Definition
master:dscd87
PSCAD name
Dual Slope Current Differential Relay
Category
Protection
Parameters
9, in 2 groups; 1 carry a unit
Read from
PSCAD 5.0.0, 2026-11-07

Read and write master:dscd87 in Python

import mhi.pscad

pscad = mhi.pscad.connect()              # the PSCAD that is open; launch() starts one
project = pscad.project("my_case")       # a case loaded in the workspace

for comp in project.find_all("master:dscd87"):   # the exact definition, namespace first
    params = comp.parameters()           # every parameter, as PSCAD holds it
    print(str(params["HT"]))             # Hold Time, in ms

comp = project.find_all("master:dscd87")[0]
comp.parameters(HT="8 [ms]")             # a value that carries a unit is written with it
  • A parameter is named exactly as in the table, letter case included: parameters() gives every one of them in a dictionary, and a name the component does not have is refused.
  • A value that carries a unit comes back as a number whose unit is only in its text, so read it as text first (str(...)) or the unit is lost. PSCAD keeps a written unit as it is given: "2500 [mohm]" stays in mohm.
  • A Choice is read and written as its symbol (the capitals in "Written as"), not as the words PSCAD shows in the dialog.
  • find_all() takes the exact definition only. A wildcard or a bare name without master: comes back empty; the Builder's px_find walks the pages for those.

The Builder's runtime does the same with the unit handled for you: px_get(comp, "HT") and px_set(...), which also records the old value so the case is put back at the end. Getting started shows them.

Main

ParameterUnitDefaultDescription
ASChoice·DEGREESInput Angles are Given inSelect Degrees or RadiansWritten as RADIANS (Radians), DEGREES (Degrees)
HTRealms4.0Hold TimeTripping criteria has to be met for this much time without an interuption for the trip signalRange 0 to 10
IS1Real·1.0Differential Current ThresholdRange 0 to 30
IS2Real·2.0Bias Current Threshold SettingRange 0.01 to 30
K1Real·0.3Lower Percentage Bias SettingRange 0 to 10
K2Real·1.5Higher Percentage Bias SettingRange 0 to 100
NameText··Name for IdentificationEnter a name for identification

Internal Output Variables

ParameterUnitDefaultDescription
IbiasText·IbiasBias Current
IdiffText·IdiffDifferential Current

Related

← master:ccvt1 CCVT · master:itoc51 Inverse Time Over Current Relay →