Relay Engineering Services APTS3 Data Sheet

Relay Engineering Services Limited

Overview

System Concept

Generators / Amplifiers

Single-Phase Current Output

Digital Inputs & Outputs

DC Source / Battery Simulator

Two-Channel Storage Scope / Voltmeter

APTS - History

www.relayeng.com

Power Systems Protection Test Equipment

APTS3 Protection Relay Test Set

• Digital Signal Processing based technology

• Advanced low-noise high-frequency switching

amplifier technology used throughout

• 2000 VA total high power / high burden outputs

• Effortlessly tests the highest burden

electromechanical relays

• 3x individually isolated 300 V sources (1 x 900 V by

series connection)

• 3x individually isolated 35 A sources

(1 x 105 A by parallel connection)

• Powerful 0 to 260 VDC battery simulator (for powering

static relays)

Now in its third generation, the APTS three-phase protection relay test set is
the flagship multipurpose relay test set manufactured by RES. The APTS
utilises the latest digital signal processing based waveform synthesis
techniques coupled with advanced low-noise switching amplifier technology.
This combination enables the APTS to deliver precision waveforms at the
highest output power available in a portable lightweight computerised test set
anywhere. The highest burden single & three-phase electromechanical relays
as well as the latest microprocessor based relays can be tested directly and
without the need for additional accessories or amplifiers.
A built-in auxiliary DC source for powering static relays is included as is a two­channel storage oscilloscope/voltmeter instrument.
The supplied Windows
from any suitable laptop computer. This comprehensive software package
offers automatic testing modes for a large number of relay types as well as
advanced manual testing facilities.

®

based software package fully controls the test set

The APTS receives commands from the controlling laptop/PC to output
defined currents and voltages to the relay under test and respond to relay
events like contact operations. All waveforms are digitally generated at high
precision and resolution to the required amplitude, frequency and phase angle.
These are amplified by the current and voltage output ampli fiers and on to the
relay under test.

The APTS has six, very high power, DC coupled sources/amplifiers. These are
tightly regulated and continuously monitored, maintaining accurate, low
distortion, voltage and current levels independently of the supply input or load.
If any APTS output deviates from its programmed setting for any reason
(open/short circuit, overburden, etc.) then the operator is warned via a
message on the PC & test set front panel.
The use of advanced miniaturised switching amplifier technology results in
very high efficiency (low heat generation) and exceptional power-to-weight.
This technology also avoids many of the performance compromises inherent
in older linear-amplifier based instruments.
The current amplifiers in particular have a very high compliance voltage
capability coupled with precise high-speed electronic regulation & software
monitoring. This guarantees clean sinusoidal waveforms are produced, even
into difficult saturating magnetic loads.
Unlike many other test sets, each and every output is individually galvanically
isolated from each other and instrument chassis, thus permitting
series/parallel connections to be made.

Under software control, the three current amplifiers can be automatically
connected in parallel or in series to obtain either 3x current or 3x compliance
voltage capabilities of the individual current amplifiers. This is especially useful
for testing IDMT overcurrent and sensitive earth fault relays (e.g. low tap
settings/high-burden induction disk CDG types). These relays have
traditionally been very difficult to accurately test without the power, extremely
high compliance voltage and tight electronic regulation and m onitoring of the
APTS amplifiers.

Relay operation is monitored by six inputs which can detect the operation of
wet or dry contacts, relay control during application of faults is provided by the
six contact outputs. The mode of operation of the i nputs is set under software
control. All Contact I/O is synchronised to waveform generation.
Additional input/output capability is offered via the interface/expansion
connector. This provides extensive analogue & digital I/O for the connection of
optional accessories like the various relay interfaces & the RES GPS Clock.

This auxiliary supply is used to provide a stable DC voltage to static relays in
the absence of a tripping supply/substation battery. A high-surge capability
overcomes the high start-up current required by many relays.

This unique built-in instrument allows the sampling of anal ogue signal s to take
place together with all six Contact Input events. The two channels are
individually isolated and have programmable gains from 10 to 500 V. The
acquisition memory is sufficient for 3.5 seconds of data to be recorded.
Acquisition is synchronised and occurs simultaneously to waveform
generation. All output as well as input waveforms & digital events are
displayed together in the Scope Display on the controlling laptop/PC.

The original APTS Mk.1 test set firs t saw service in 1983. Initially developed
within what is now the UK's National Grid Company, the Mk.1 APTS was the
world’s first truly portable computerised protection relay test set. The APTS
Mk.1 and later Mk.2 test sets have since become the standard automatic
protection relay test set used in the UK as well as in many other countries.
The Mk.3 APTS benefi ts from this long tradition and nearly two decades of
cumulative field experience to offer a thoroughly effective and proven solution
for today’s relay testing requirements.

625 East Bunker Court Vernon Hills, IL 60061-1844 Toll-free: 800-358-5525

Fax: [phone] E-mail: [e-mail]

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