Atec Megger-ODEN-AT - Manual

ODEN AT
Primary Current Injection Test System
Description
This powerful test system is designed for primary injection testing
of protective relay equipment and circuit breakers. It is also used
to test the turns ratio of current transformers and for other
applications that require high variable currents.
The system consists of a control unit together with one, two or
three current units. There are three versions of the current unit: S,
X and H. The S and X current units are identical except that the X
unit has an additional 30/60 V output. The H unit is rated for even
higher current. This makes it possible to configure an ODEN AT
system in a suitable way. All parts are portable, and ODEN AT can
be quickly assembled and connected.
The control unit has many advanced features – a powerful
measurement section for example, that can display turns ratio as
well as time, voltage and current. A second measurement channel
can be used to measure an additional current or voltage. Current
transformer turns ratio, impedance, resistance, power, power
factor (cos φ) and phase angle are calculated and shown in the
display. Current and voltage can be presented as percentages
of nominal value. The fast-acting hold function freezes short-
duration readings on the digital display when the voltage or contact
signal arrives at the stop input, the object under test interrupts the
current or injection is stopped
„ „ Testing current transformers
For turns ratio testing, the primary current and either the
secondary current or the turns ratio are displayed simultaneously.
Since the turns ratio is displayed directly as the nominal value
(1000/5 for example), no further calculation is needed. Burden of
secondary circuits can be measured and presented in VA.
„ „ Polarity testing
The currents phase displacement is shown, and the polarities of
the outputs are clearly marked.
„ „ Heat runs
ODEN AT is ideal for performing heat runs. Current can be
applied continuously or through programmable intervals. The
times can be shown in minutes and hours which facilitates long-
term testing capability.
„ „ Automatic reclosers and sectionalizers
ODEN AT can also be set to test circuit breakers with reclosing
relays. Operating limits, partial times, total times and the number
of operations before lockout can be measured. User-selectable
reclosing sequences can be programmed for testing sectionalizers.
„ „ Testing integrity of ground grids and safety-ground devices
One way to test ground grids is by injecting current between a
reference ground and the ground to be tested and measuring the
voltage drop and the percentage of current flowing through the
ground grid. The type X current unit included with ODEN AT
is designed for this type of application. Personal safety grounds
must be tested at rated current, a task for which ODEN AT is well
suited.
Application
„ „ Primary current injection testing and breaker testing
These tests require high currents and the ability to measure very
short duration, current flow. ODEN AT has been designed
especially to meet these needs. No extra contacts are needed to
measure the operating time of a low-voltage breaker. Testing stops
at the instant when the main breaker contacts open to interrupt
the current. Output current initiation is synchronized with the
currents zero-crossover point to ensure good repeatability and
minimized DC offset.
„ ▪ Most Advanced Primary Current Injection
Test System to simplify all types of
switchgear and CT commissioning, ground
grid, circuit breaker testing and more
„ ▪ Modular design to permit optimal
user configuration of output current
vs. unit size
„ ▪ Compact transport cart facilitates
portability into switchgear rooms
with limited space
„ ▪ Unique I/30 function allows the current to
be pre-set using low current to prevent
test sample heating, thus eliminating
corruption of test result
ODEN AT
Primary Current Injection Test System