ABB RELION REX640 Technical Manual page 1110

Protection and control

Hide thumbs Also See for RELION REX640:

Table of Contents

Protection functions

Function block

Figure 622: Function block symbol

Functionality

The three-phase overload protection for shunt capacitor banks function COLPTOC

provides single-phase, two-phase and three-phase protection against overloads

caused by harmonic currents and overvoltages in shunt capacitor banks. The

operation of overload and alarm is based on the peak value of the integrated current

which is proportional to the voltage across the capacitor.

The overload function operates with IDMT characteristic and an alarm function

operates with DT characteristic.

COLPTOC provides undercurrent protection to detect disconnection of the

capacitor. COLPTOC has breaker reclosing inhibit feature to enable complete

capacitor discharging before breaker reclosing after it has operated.

COLPTOC contains blocking functionality. It is possible to block the function

outputs, timers or the function itself.

Analog channel configuration

COLPTOC has one analog group input which must be properly configured.

Table 1053: Analog inputs

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 COLPTOC can be described using a module diagram. All the

modules in the diagram are explained in the next sections.

See the preprocessing function blocks in this document for the possible

signal sources.

Three-phase currents

1MRS759142 F

Technical Manual