PCS S Series
PCS-978S Transformer Relay Reliable differential CT circuit failure supervision. The relay
can detect multi-phase CT wire-break, multi-side CT
wire-break, short-circuit, and other complex situation. The
corresponding logic setting can be used to select blocking
differential protection or not, in case of CT circuit failure.
• Multiple inrush current blocking options are provided.
Self-adaptive inrush current blocking criterion can ensure the
relay fast operation for transformer energized on to a slight
fault, meanwhile it will avoid the unwanted operation in the
case of the energization inrush current caused by energizing
transformer with no load, the recovery inrush current caused
PCS-978S has been designed specifically for the protection of by cutting off the transformer external fault, and the
various type power transformers, including two-winding sympathetic inrush current.
transformers, three-winding transformers (up to 6 branches), as • Biased DPFC differential protection is regardless of load
well as auto-transformers in any voltage level. PCS-978S is the current and is sensitive to small internal fault current within the
main protection for the transformer and contains many other transformer. Its anti CT saturation performance is also strong.
protection, control and monitoring functions. With its modular
structure, flexibility and the powerful PCS-Studio engineering tool, • The unique power swing blocking releasing logic without
PCS-978S offers future-oriented system solutions with high setting and can properly supervise distance protection during
investment security and low operating costs. power swing, which ensures distance protection to operate
correctly for internal faults during power swing, and prevents
distance protection from mal-operation during power swing.
Functions
Protection and Control
• Transformer differential protection (87T)
Conventional and sensitive biased differential elements are
available for fast and sensitive fault clearance. The
conventional biased differential element can be with inrush
current blocking, while the sensitive biased differential element
can be further blocked by CT saturation, over excitation and
CT failure. Instantaneous differential element instantaneously
responds and clears serious internal faults without any
restraining characteristics and blocking elements. DPFC
differential element is immune to load fluctuations and provides
high sensitivity for turn-to-turn faults and high impedance
faults.
Features • Inrush blocking
• High degree of functional integration and flexible configuration Two methods are provided for inrush blocking: waveform
modes, transformer main protection and back-up protection distortion method and harmonic method. In the waveform
can be integrated in one device, or be separated in two distortion method, the symmetry principle is utilized to detect
devices. interrupted and unsymmetrical inrush currents. The harmonics
• Up to 36 analog inputs can be provided and configured method relies on the 2nd and 3rd harmonics in order to
flexibly. determine the inrush current. The self-adaptive blocking mode
and phase-to-phase cross-blocking mode are both provided for
• The tripping output contacts can be configured by tripping
inrush blocking.
matrix, which is flexible, convenient and suitable to any mode
of tripping. • CT saturation blocking
• The relay supports at most 6 branches differential protection. The The 2nd and 3rd harmonics are both employed to detect both
transformer angle can be adjusted flexibly, and any transformer steady-state CT saturation and transient CT saturation. In
angle compensation mode is supported and any side can be addition, the time intervals between difference current and
chosen as the reference side of differential protection. restraint current are utilized to distinguish internal faults and
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Specifications
Electrical Specifications
AC Current Input
Phase rotation ABC or ACB
Nominal frequency (fn) 50Hz, 60Hz
Rated current (In) 1A/5A (settable)
Linear to 0.01A~200A
Thermal withstand
-continuously 20A
-for 10s 150A
-for 1s 500A
-for half a cycle 1250A
Burden <0.05VA/phase @1A, <0.25VA/phase @5A
AC Voltage Input
Phase rotation ABC or ACB
Nominal frequency (fn) 50Hz, 60Hz
Rated voltage (Un) 100V~130V
Linear to 1V~300V
Thermal withstand Phase-to-ground Phase-to-phase
-continuously 300V 519V
-10s 600V 1038V
-1s 660V 1141V
Burden at rated <0.01VA/phase @100V
Power Supply
Standard IEC 61000-4-29:2000
Rated voltage 110Vdc/125Vdc/220Vdc/250Vdc 110Vac/220Vac
Permissible voltage range 88~300Vdc 88~275Vac
Permissible AC ripple voltage ≤15% of the nominal auxiliary voltage
Burden
Quiescent condition <30W
Operating condition <35W
Transducer Input
Standard IEC 60255-1: 2009
Input range -20mA~20mA -10V~10V
Input resistance 230Ω >1MΩ
Accuracy 0.1% 0.1%
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PCS S Series
RTD PT10, PT100, PT1000, CU50, CU100
Types 3-wire, 2-wire
PT10, PT100, PT1000: -200°C ~ 850°C
Range
CU50, CU100: -50°C ~ 150°C
Accuracy 0.5°C (3-wire, environment temperature: 25°C)
Binary Input: Settable pickup voltage and dropoff voltage
Rated voltage 110V 125V 220Vdc 250Vdc
Rated current drain 0.73mA 0.83mA 1.47mA 1.67mA
On value (default set) 69.3~132Vdc 78.75~160Vdc 138.6-264Vdc 157.5~300Vdc
Off value (default set) <55V <62.5V <110Vdc <125V
Maximum permissible voltage 350Vdc
Withstand voltage 2000Vac, 2800Vdc (continuously)
Response time for logic input ≤1ms
Binary Input: Settable pickup voltage and dropoff voltage
Rated voltage 24V 48V
Rated current drain 0.16mA 0.32mA
On value (default set) 15.12~28.2Vdc 30.24~57.6Vdc
Off value (default set) <12V <24V
Maximum permissible voltage 350Vdc
Withstand voltage 2000Vac, 2800Vdc (continuously)
Response time for logic input ≤1ms
Binary Output: Tripping/signaling contact
Output mode Potential free contact
Max. system voltage 250Vac, 300Vdc
Continuous carry 10A
Pickup time (Typical value) <5ms
Dropoff time (Resistive load) <6ms
0.5A@48Vdc
0.35A@110Vdc
Breaking capacity (L/R=40ms) 0.30A@125Vdc
0.20A@220Vdc
0.15A@250Vdc
0.5A@48Vdc
0.35A@110Vdc
Cyclic Capacity
0.30A@125Vdc
(2.5 cycle/second, L/R=40ms)
0.20A@220Vdc
0.15A@250Vdc
30A@3s
Short duration current
50A@1s
Durability (Loaded contact) 10000 operations
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Binary Output: Heavy-capacity tripping contact
Output mode Potential free contact
MOV Protection (maximum voltage ) 350Vdc, 275Vac
Continuous carry 10A
Pickup time (Typical value) <1ms
Dropoff time (Resistive load) <10ms
10A@48V
10A@110V
Breaking capacity (L/R=40ms)
10A@125V
10A@250V
10A@48V L/R=40ms
Cyclic Capacity (4cycles in 1 second,
10A@110V L/R=40ms
followed by 2 minutes idle for
10A@125V L/R=40ms
thermal dissipation)
10A@250V L/R=20ms
30A@3s
Short duration current
50A@1s
Durability (Loaded contact) 10000 operations
Mechanical Specifications
Chassis color Silver grey
Approx. 8.66kg (6U, 1/2)
Weight per device
Approx. 15.83kg (6U, 1/1)
Chassis material Aluminum alloy
Location of terminal Rear panel of the device
Device structure Plug-in modular type @ rear side, integrated front plate
Protection Class
Standard IEC 60529-2013
Front side IP52
Other sides IP50
Rear side, connection terminals IP20
Ambient Temperature and Humidity Range
Standard IEC 60255-1:2009
Operating temperature -40°C to +80°C (Readability of display may be impaired below -20°C and above 70°C)
Transport and storage temperature range -40°C to +80°C
Permissible humidity 5%-95%, without condensation
Pollution degree II
Altitude <3000m
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PCS S Series
Communication Port
EIA-485 Port
Baud rate 4.8kbit/s, 9.6kbit/s, 19.2kbit/s, 38.4kbit/s, 57.6kbit/s, 115.2kbit/s
Protocol IEC 60870-5-103:1997
Max. capacity 32
Max. transmission distance 500m
Safety level Isolation to ELV level
Twisted pair Screened twisted pair cable
Copper Ethernet Port
Connector type RJ45
Transmission rate 100Mbits/s
Transmission standard 100Base-TX
Max. transmission distance 100m
Protocol IEC 60870-5-103:1997, DNP 3.0 or IEC 61850
Safety level Isolation to ELV level
Optical Fibre Port: For Station Level
Characteristic Glass optical fiber
Connector type LC
Fibre type Multi mode
Max. transmission distance 2km
Wave length 1310nm
Transmission power 50μm: -24dBm 62.5μm: -20dBm
Minimum receiving power Min. -31.0dBm
Margin 50μm: -7dBm 62.5μm: -9dBm
Optical Fibre Port: For Process Level
Characteristic Glass optical fiber
Connector type LC
Fibre type Multi mode
Max. transmission distance 2km
Wave length 1310nm
Transmission power -20.0dBm ~ -14.0dBm
Minimum receiving power Min. -30.0dBm
Margin Min. +10.0dBm
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Optical Fibre Port: For Synchronization Port
Characteristic Glass optical fiber
Connector type ST
Fibre type Multi mode
Wave length 850nm
Peak optical input power
Logic level HIGH Max. -40dBm
Logic level LOW Max. -10dBm, Min -24dBm
Print Port
Type RS-232
Baud Rate 4.8kbit/s, 9.6kbit/s, 19.2kbit/s, 38.4kbit/s, 57.6kbit/s, 115.2kbit/s
Printer type EPSON® 300K printer
Safety level Isolation to ELV level
Clock Synchronization Port
Type Serial port BNC Connector
Input Demodulated IRIG-B or PPS
Nominal voltage 5Vdc+10%
Maximum voltage 8Vdc
Input impedance 2.5kΩ >1kΩ
Isolation 500Vdc 1.5kV (rms) for 1 min
Type Tests
Environmental Tests
Dry cold test IEC60068-2-1:2007
Dry heat test IEC60068-2-2:2007
Damp heat test, cyclic IEC60068-2-30:2005
Mechanical Tests
Vibration IEC 60255-21-1:1988 Class I
Shock and bump IEC 60255-21-2:1988 Class I
Electrical Tests
Standard IEC 60255-27:2013
Dielectric tests Test voltage 2kV, 50Hz, 1min
Impulse voltage tests Test voltage 5kV
Overvoltage category III
Insulation resistance measurements Isolation resistance >100MΩ@500VDC
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PCS S Series
Electromagnetic Compatibility
IEC 60255-26:2013
1MHz burst disturbance test Common mode: class III 2.5kV
Differential mode: class III 1.0kV
IEC 61000-4-2-2008
Electrostatic discharge test For contact discharge: 8kV
For air discharge: 15kV
IEC 60255-26:2013 class III
Frequency sweep
Radiated amplitude-modulated
Radio frequency interference tests 10V/m (rms), f=80~1000MHz, 14000~2700MHz
Spot frequency
Radiated amplitude-modulated
10V/m (rms), f=80MHz/160MHz/450MHz/900MHz
IEC 60255-26:2013
Fast transient disturbance tests Power supply, I/O, Earth: class IV, 4kV, 5kHz, 5/50ns
Communication terminals: class IV, 2kV, 5kHz, 5/50ns
IEC 60255-26:2013
Surge immunity test Power supply, AC input, I/O port: class IV, 1.2/50us
Common mode: 4kV
Differential mode: 2kV
IEC 60255-26:2013
Conducted RF electromagnetic disturbance Power supply, AC, I/O, Comm. Terminal: Class III, 10Vrms, 150 kHz~80MHz
Spot frequency
10V/m (rms), f=27MHz/68MHz
IEC 61000-4-8:2009
Power frequency magnetic field immunity
Class V, 100A/m for 1min, 1000A/m for 3s
IEC 61000-4-9:2016
Pulse magnetic field immunity
Class V, 6.4/16μs, 1000A/m for 3s
IEC 61000-4-10:2016
Damped oscillatory magnetic field immunity
Class V, 100kHz & 1MHz–100A/m
IEC 60255-26:2013
Conducted emission 0.15MHz ~ 0.50MHz: 79dB(μV) quasi peak, 66dB(μV) average
0.50MHz ~ 30MHz: 73dB(μV) quasi peak, 60dB(μV) average
IEC 60255-26:2013
Below 30MHz ~ 230MHz: 40dB(μV/m) quasi peak @10m, 50dB(μV/m) quasi peak @3m
Radiated emission 1GHz 230MHz ~ 1000MHz: 47dB(μV/m) quasi peak @10m, 57dB(μV/m) quasi peak @3m
Above 1GHz ~ 3GHz: 56dB(μV/m) average, 76dB(μV/m) peak @3m
1GHz 3GHz ~ 6GHz: 60dB(μV/m) average, 80dB(μV/m) peak @3m
IEC 60255-26:2013
Voltage dips Up to 200ms for dips to 40% of rated voltage without reset
Auxiliary power supply performance 50ms for interruption without rebooting without energy
storage board (Typical configuration)
Voltage short interruptions
500ms for interruption without rebooting with energy
storage board (Typical configuration)
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Terminals
Connection Type Wire Size
AC current Screw terminals, 1.5~4mm2 lead
AC voltage Screw terminals, 0.8~4mm2 lead
Power supply Screw terminals, 0.8~4mm2 lead
Contact I/O Screw terminals, 0.8~4mm2 lead
Grounding (Earthing) Connection BVR type, 0.8~4mm2 lead
Measurement Scope and Accuracy
Item Range Accuracy
Phase range 0° ~ 360° ≤±1°
Frequency fn±3 Hz ≤0.01Hz
Currents from protection measurement current transformers
≤ 1.0% of rating (0.05~1.00In)
Current 0.05~4.00In
≤ 0.5% of applied quantities (1.00~4.00In)
≤ 1.0% of rating (0.05~1.00Un)
Voltage 0.05~1.50Un
≤ 0.5% of applied quantities (1.00~1.50Un)
0.05~1.50Un ≤ 2.0% of rating (0.05~1.00In, 0.05~1.00Un)
Active power (W)
0.05~4.00In ≤ 1.0% of applied quantities (1.00~4.00In, 1.00~1.50Un)
0.05~1.50Un ≤ 2.0% of rating (0.05~1.00In, 0.05~1.00Un)
Reactive power (VAr)
0.05~4.00In ≤ 1.0% of applied quantities (1.00~4.00In, 1.00~1.50Un)
0.05~1.50Un ≤ 2.0% of rating (0.05~1.00In, 0.05~1.00Un)
Apparent power (VA)
0.05~4.00In ≤ 1.0% of applied quantities (1.00~4.00In, 1.00~1.50Un)
Management Function
Control Performance
Control mode Local or remote
Accuracy of local control ≤1s
Accuracy of remote control ≤3s
Clock Performance
Real time clock accuracy ≤1s/day
Accuracy of GPS synchronization ≤1ms
External time synchronization IRIG-B (200-98), PPS, IEEE1588 or SNTP protocol
Fault and Disturbance Recording
Duration & Recording position Settable pre-disturbance, post-disturbance and maximum recorded duration
Sampling rate Up to 9.6kHz
Binary Input Signal
Resolution of binary input signal ≤1ms
Binary input mode Potential-free contact
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