Controlled Switching — Buyer´s Guide
N-2
Edition 2, 2006-09
Technical Information
Quality, Testing and Commissioning
Switchsync™ L183
For line switching applications using Switch-
sync™ controller L83, a different verification
procedure is needed. Verification of the func-
tion under actual intended operating condi-
tions - fault tripping followed by a reclosing
operation - is not feasible. As a substitute,
however, it is normally possible to arrange
manual tripping of the line under no-load
conditions, followed by a reclosing operation.
A simplified commissioning procedure should
include control of the energizing instants for
the three poles with respect to the phase
angle of the source side voltages, and based
on the measured trapped voltages.
The following should be recorded:
- Busbar voltages (or at least the reference
voltage)
- Line current in each phase
- Output commands from the controller
- Functioning times of precision auxiliary con-
tacts (if adaptation control is used)
After each switching operation, the display
information should be noted and the ener-
gizing instants checked with respect to the
measured trapped voltages. Guidelines for
determination of appropriate energizing in-
stants, dependent on the measured trapped
charge, are given in the product manual. In
addition, the signals from the auxiliary con-
tacts can be used to verify that realistic pre-
arcing times are reached.
Upon commissioning, the controller also
makes a self-check of the polarity of its con-
nections. It will give an alarm if the recorded
busbar voltage and load side voltage are dif-
ferent when the circuit breaker is closed.
Switchsync™ T183
To verify performance, the following should
be recorded:
- Busbar voltages (or at least the reference
voltage)
- Current in each phase
- Output commands from controller
- Functioning times of precision auxiliary con-
tacts (if adaptation control is used)
The best way to verify the controlled switch-
ing function is to record the actual inrush
currents during a few test operations. Limited
amplitude and good symmetry of the cur-
rents are indications of proper function.
The energizing instants cannot be checked
from the inrush current recordings, due to
the non-sinusoidal wave-shape. In order to
check the energizing instants, the load side
voltages must also be recorded. However,
for transformers with magnetically dependent
phases, only the energizing instant for the
first energized phase can be determined.
After each switching operation, the display
information should be noted. Displayed clos-
ing times should be compared to recorded
closing times.
Upon commissioning, the controller also
makes a self-check of the polarity of its con-
nections. It will give an alarm if the recorded
busbar voltage and load side voltage are dif-
ferent when the circuit breaker is closed.
General
Switchsync™ controllers are maintenance-
free. After successful commissioning tests,
there is no need for any further periodic
checks of function, provided that operations
are performed in adaptive mode. For applica-
tions in which no adaptive function is used,
it is advisable to occasionally record a few
operations after some years in service.
Commissioning
