Alarm annunciator • Capacitor bank protection • Motor protection • Transformer protection • Line protection • Voltage protection • Bay control • Generator protection • Synchronizer • Automatic Voltage Regulator • Power Measurement • Power Factor Controller
AQ-ONE is a modular protection, control and automation platform with up to 14 expansion slots, depending on the enclosure size. Expansion modules can be used to add digital and analogue I/O, RTD temperature monitoring, arc protection and communication interfaces.
AQ-ONE is built around application function packages. Each package includes a predefined set of protection, control and monitoring functions for a specific application. Additional function packages can be licensed separately and added where required.
Functions included in the package
• Alarm annunciation for protection, control and monitoring signals
• Up to 128 configurable alarms
• Alarm grouping and indication through the relay HMI and communication interfaces
Functions included in the package i
• Capacitor bank module
• Capacitor bank overload protection (49OL)
• Capacitor bank neutral unbalance protection (50UB)
• Capacitor bank current unbalance protection (46C)
• Non-directional overcurrent protection (50/51; I>)
• Non-directional earth fault protection (50N/51N; I0>)
• Negative sequence / phase current reversal / current unbalance protection (46R/46L/46; I2>)
• Harmonic overcurrent protection (50H/51H/68H; Ih>)
• Circuit breaker failure protection (50BF/52BF; CBFP)
• Restricted earth fault and cable end differential protection (87N)
Functions included in the packagei i
• Non-directional overcurrent protection (50/51; I>)
• Non-directional earth fault protection (50N/51N; I0>)
• Negative sequence / phase current reversal / current unbalance protection (46/46R/46L; I2>)
• Harmonic overcurrent protection (50H/51H/68H; Ih>)
• High- or low-impedance restricted earth fault;
Cable end differential (87N; I0d>)
• Circuit breaker failure protection (50BF/52BF; CBFP)
• Line thermal overload protection (49F)
• Switch-on-to-fault
• Auto-recloser (79)
• Cold load pick-up
Functions included in the packagei
• Non-directional overcurrent protection (50/51; I>)
• Non-directional earth fault protection (50N/51N; I0>)
• Negative sequence overcurrent; / phase current reversal / current unbalance protection (46/46R/46L; I2>)
• Harmonic overcurrent protection (50H/51H/68H)
• Restricted earth fault protection; Cable end differential (87N; I0d>)
• Circuit breaker failure protection (50BF/52BF; CBFP)
• Motor status monitoring
• Motor thermal overload (49M; TM>)
• Motor startup / locked rotor monitoring (48/14; Ist>)
• Frequent start protection (66; N>)
• Non-directional undercurrent protection (37; I<)
• Mechanical jam protection (51M; Im>)
• Running hour counter
Functions included in the packagei i
• Non-directional overcurrent protection (50/51; I>)
• Non-directional earth fault protection (50N/51N; I0>) • Negative sequence / phase current reversal / current unbalance protection (46/46R/46L; I2>) • Harmonic overcurrent protection (50H/51H/68H; Ih>) • Circuit breaker failure protection (50BF/52BF; CBFP) • High- or low-impedance restricted earth fault and cable end differential protection (87N; I0d>) • Transformer thermal overload protection (49T; TT>)
Functions included in the packageii
• Non-directional overcurrent (50/51; I>)
• Non-directional earth fault (50N/51N; I0>)
• Negative sequence overcurrent; Phase current reversal; Current unbalance (46/46R/46L; I2>)
• Harmonic overcurrent (50H/51H/68H; Ih>)
• Circuit breaker failure protection (50BF/52BF; CBFP)
• High- or low-impedance restricted earth fault; Cable end differential (87N; I0d>)
• Line thermal overload (49F; TF>)
• Teleprotection (85)
• Auto-recloser (79)
• Switch-on-to-fault (SOFT)
• Cold load pick-up (CLPU)
Functions included in the packagei
• Overvoltage (59; U>)
• Undervoltage (27; U<)
• Neutral overvoltage (59N; U0>)
• Sequence voltage (47/27P/59PN; U1/U2>/<)
• Ovefrequency and underfrequency (81O/81U; f>/<)
• Rate-of-change of frequency (81R; df/dt>/<)
• Low-voltage ride-through (27T; LVRT)
• Underfrequency load shedding (81LSH; UFLS)
• Volts-per-hertz (24; V/Hz>)
• Zero sequence recloser (79N; U0> RECL)
• Synchrocheck (25; ΔV/Δa/Δf)
• Pole slip (78)
• Vector jump (78; Δφ)
Functions included in the packagei
• 10 additional indicator objects (CIN 11…20)
• Auto-recloser (79)
• Synchrocheck (25; ΔV/Δa/Δf))
Functions included in the packagei
• Comprehensive protection package for synchronous generators and generator-transformer units
• Includes overcurrent, earth fault, voltage and frequency protection functions
• Includes synchrocheck, pole slip, underexcitation and power factor protection functions
• Non-directional overcurrent (50/51; I>)
• Non-directional earth fault (50N/51N; I0>)
• Negative sequence overcurrent; Phase current reversal; Current unbalance (46/46R/46L; I2>)
• Harmonic overcurrent (50H/51H/68H; Ih>)
• Circuit breaker failure protection (50BF/52BF; CBFP)
• High- or low-impedance restricted earth fault; Cable end differential (87N; I0d>)
• Directional overcurrent (67; Idir>)
• Directional earth fault (67N/32N; I0dir>)
• Intermittent earth fault (67NT; I0int>)
• Overvoltage (59; U>)
• Undervoltage (27; U<)
• Neutral overvoltage (59N; U0>)
• Zero sequence recloser (U0> RECL)
• Sequence voltage (47/27P/59PN; U1/U2>/<)
• Ovefrequency and underfrequency (81O/81U; f>/<)
• Rate-of-change of frequency (81R; df/dt>/<)
• Low-voltage ride-through (27T; LVRT)
• Underfrequency load shedding (81LSH; UFLS)
• Generator thermal overload (49M; TM>)
• Power protection (32; P,Q,S>/<)
• Power factor protection (55; PF>)
• Underexcitation (40; Q<)
• Underimpedance (21U; Z<)
• Underreactance (21/40; X<)
• Volts-per-hertz (24; V/Hz>)
• 100% stator earth fault (64S; U03rd>)
• Voltage-restrained overcurrent (51V; Iv>)
• Inadvertent energizing (50/27; I>U– Synchrocheck (25; ΔV/Δa/Δf)
• Pole slip (78)
• Vector jump (78; Δφ)
• Running hour counter
Functions included in the packagei
• Synchronizer (25; ΔV/Δa/Δf)
Function Description
• Automatic synchronisation of generators to power grids
• Compares voltage magnitude, frequency and phase angle between generator and grid
• Sends increase and decrease commands to the voltage regulator (AVR)
• Sends increase and decrease commands to the turbine governor
• Allows synchronisation limits and operating settings to be adjusted
• Supports pre-closing time compensation for circuit breaker operation
• Automatically adjusts the pre-closing angle according to slip frequency
• Sends a circuit breaker close command when voltage, frequency and phase-angle conditions are satisfied
Functions included in the packagei
• Transformer AVR for up to four (4) parallel transformers (90)
Function Description
• Automatic voltage regulation using transformer tap changers
• Independent or parallel voltage regulation modes
• Control of up to four transformer tap changers in parallel
• Master/Follower and Circulating Current operating modes
• GOOSE-based communication between parallel regulators
• Individual transformer feedback and status monitoring
Functions included in the package
• Programmable stage (99)
• Running hour counter
Power measurements
• Three-phase apparent power (S)
• Three-phase active power (P)
• Three-phase reactive power (Q)
• Three-phase power factor
• Three-phase active and reactive power direction
• Per-phase apparent power (L1, L2, L3)
• Per-phase active power (L1, L2, L3)
• Per-phase reactive power (L1, L2, L3)
• Per-phase active and reactive power direction
Functions included in the packagei
• Power Factor Controller (90PF)
Function Description
• Automatic power factor correction using capacitor bank control
• Controls capacitor bank switching to maintain a user-defined power factor target (cos φ)
• Monitors reactive power and automatically connects or disconnects capacitor stages as required
• Supports up to five capacitor banks
• Automatic and manual operating modes
• Configurable power factor and kVAr control settings
• Event logging for capacitor bank switching and controller operation
Functions included in the package
• Single-pole non-directional overcurrent protection (50/51) for overcurrent and short-circuit protection
• Two independent protection stages for single-phase applications
• Configurable pick-up levels and operating delays
• Single-pole object control and monitoring (OBJS)
Functions included in the packagei
• Line differential protection (Idb>/Idi>; 87L) for two-terminal transmission lines
• Biased differential characteristic with two operating slopes and an unrestrained differential stage
• Differential calculation based on synchronised current measurements from both line ends
• Fast CT supervision for local and remote CT circuit monitoring
• Load supervision to prevent unwanted operation during significant load variations
• Local and remote breaker control logic for line differential applications
• Process bus support with master and sub-node architecture
• Transformer-in-line compensation for applications where a transformer is located within the protected zone
Same function set as the Voltage Protection application package
Same function set as the Automatic Voltage Regulator application package
Functions included in the package
• Machine differential protection for generator, motor and transformer applications
• Differential protection functions: 87G / 87M / 87T
• Integrated restricted earth fault protection (87N)
• Requires two CT modules
• Available as an additional function package for Generator Protection, Motor Protection and Transformer Protection configurations
Functions included in the package
• Synchronous motor protection package for Motor Protection configurations
• Requires CT and VT measurement modules
• Available as an additional function package when Motor Protection is selected
• Uses current and voltage measurements for synchronous motor protection applications
Requires additional expansion slots depending on the selected hardware configuration
Same function set as the Synchronizer application package
Functions included in the packageii
• Directional overcurrent protection (67)
• Directional earth fault protection (67N/32N)
• Intermittent earth fault protection (67NT)
• Power protection (32)
• Neutral overvoltage protection (59N)
• Fault locator (21FL)
• Distinguishes between forward and reverse faults using current and voltage measurements
• Requires CT and VT measurement modules
Functions included in the packagei
• Distance protection (21)
• Up to ten independently configurable protection zones
• Zones can be set for forward, reverse or non-directional operation
• Quadrilateral characteristics for flexible zone settings
• Load encroachment supervision
• Power swing blocking (68)
• Out-of-step protection (78)
• Stable and unstable power swing detection
• Uses current and voltage measurements to calculate loop impedances and impedance angles
• Requires CT and VT inputs
Same function set as the Power Measurement application package
177 x 127 x 174 mm (H x W x D)
177 x 177 x 174 mm (H x W x D)
177 x 226 x 182 mm (H x W x D)
AQ-ONE is built around a modular hardware platform. Expansion modules can be fitted as required, allowing the hardware configuration to be matched to the application.
Digital I/O modules, RTD modules, arc protection modules and other expansion modules can be installed in any available slot. The final two slots can also accommodate communication modules.
When the relay starts up, it automatically identifies all installed modules and checks that the hardware matches the configured device. Any discrepancy is reported as a hardware configuration error.
Small, medium or large enclosure, same firmware and same logic throughout. Train once, work on any AQ-ONE afterwards.
You order the function packages your application needs on the relay, and can add or switch them later as requirements change.
Every slot takes any add-on card, so I/O can be added later without swapping the unit. The end slots take communication cards too, ready for Ethernet or IRIG-B when needed.
Harmonic tracking runs out to the 31st order, well beyond what most protection relays track. Useful on sites with inverter-based generation or heavy power electronics, where higher-order harmonics matter.
AQ-ONE carries over forty protection functions plus monitoring and control in a single unit. Fewer devices per bay means less panel space, less wiring and fewer spares to hold.
IEC 61850 with GOOSE, Modbus, DNP3, IEC 101/104, IEC 103, SPA and OPC UA are all built in. No protocol converter, no bespoke integration per site.
Current measurement to within 0.5% across most of the range, angle accuracy tight enough for differential and distance schemes. Figures that hold up when a client or regulator asks.
Configuration, settings and commissioning all run through AQtivate. Less time training engineers on separate software for each relay.
Built for power systems up to 150 kV, with line, distance and differential protection function packages covering both overhead lines and cables.
Generator protection, automatic voltage regulator and synchronizer functions cover the core protection and control needs of a generating unit, including parallel operation with the network.
Motor protection and synchronous motor protection packages are built for the start-up, running and fault conditions typical of pumps, compressors and other large drives.
Capacitor bank protection and the power factor controller function are built specifically for reactive power compensation schemes.
A dedicated transformer protection package, alongside differential and thermal overload protection functions, covers transformer-specific fault conditions.
Feeder protection, bay control and the alarm annunciator function suit feeder-level protection and the wider control and signalling needs of a substation.
