Functionality - ABB RELION REX640 Technical Manual

Section 4
Protection functions
4.9.3
4.9.4
4.9.5
984

Functionality

The arc protection function ARCSARC detects arc situations in air-insulated metal-
clad switchgears caused by, for example, human errors during maintenance or
insulation breakdown during operation.
The function detects light from an arc either locally or via a remote light signal. The
function also monitors phase and residual currents to be able to make accurate
decisions on ongoing arcing situations.
The function contains a blocking functionality. Blocking deactivates all outputs and
resets timers.
Analog channel configuration
ARCSARC has two analog group inputs which must be properly configured.
Table 925: Analog inputs
Input
1)
I3P
1)
IRES
1) Can be connected to GRPOFF if "Light only" or "BI controlled" operation modes are used
See the preprocessing function blocks in this document for the
possible signal sources. The GRPOFF signal is available in the
function block called Protection.
Improper analog channel configuration causes a validation error if the analog
channels are not completely configured or they do not match with certain settings. For
troubleshooting, check the contents of this chapter and also the preprocessing blocks
in this document. The configuration can be written to the protection relay once the
mismatch is corrected.
Operation principle
The function can be enabled and disabled with the Operation setting. The
corresponding parameter values are "on" and "off".
The operation of ARCSARC can be described with a module diagram. All the
modules in the diagram are explained in the next sections.
Description
Three-phase currents
Necessary when the operation mode "Light
+current" is used
Residual current (measured or calculated)
Necessary when the operation mode "Light
+current" is used
1MRS759142 C
REX640
Technical Manual