Kyongbo Electronics GDR-AEF01 User manual

Digital Overcurrent & Ground Overvoltage &
Selective Ground Relay Manual
TYPE : GDR-AEF01
2006. 7. 18
Version 1.00
Kyongbo Electronics Co., Ltd.

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Safety Precautions
This document is for the safety of the user, and to prevent property damage.
Be sure to read the user manual carefully, and use the product accordingly.
The user manual must be kept in a place where it can be easily seen by the product
user.
WARNING
CAUTION
This symbol indicates the
possibility of death or serious
injury.
This symbol indicates the
possibility of injury or damage to
properties only.
SYMBOLS
Be sure not to do.
Be sure to follow the instruction.

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WARNING
• Do not perform any wiring work while the power is on or
the product is in operation.
It may cause an electric shock.
• Must verify the status of the grounding connection before
starting the operation.
Otherwise, it may cause an electric shock, damage, or a fire.
• Do not operate the product with wet hands.
It may cause an electric shock.
• Do not use if the clothing of the cable is damaged.
It may cause an electric shock.
• Do not perform any wiring work when the main cable is
live.
It may cause an electric shock, and a damage or a fire by the
charged voltage of the converter.
• Do not disassemble the product even if the power is not
on, except for wiring or maintenance.
It may cause an electric shock by the charged current in
the product.
• Let the electrical technician to perform wiring, test run,
and maintenance.
Otherwise, it may cause an electric shock or a fire by a wrongful
operation.
• Perform terminal work when cutting a cable.
Otherwise, it may cause an electric shock from the naked part of the
cable.
• Place the terminal cover on the terminal in the back after
the wiring work.
Otherwise, it may cause an electric shock.

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• Apply the rated power to the power source terminal.
Otherwise, it may cause a damage to the product or a fire.
• Follow the rated load on the input and output
connections.
Otherwise, it may cause a damage to the product or a fire.
• Prevent screws, metal parts, water, or oil from entering
the product.
It may cause a damage to the product or a fire.
• Do not let the product be exposed to a direct sunlight.
It may cause a damage to the product.
• Extract and insert Case on a leveled surface.
Otherwise, it may cause a damage to the product.
• Do not store the product in a humid or a dusty area.
It may cause a damage to the product.
CAUTION

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Table of Contents
Order of Titles
1. General Features ···································································································································· 9
2. Technical Data ····································································································································· 10
2.1 Voltage, Current Input ·················································································································· 10
2.2 Rated Control Source Voltage ····································································································· 10
2.3 Rated Frequency ···························································································································· 10
2.4 Case ················································································································································· 11
2.5 Time Overcurrent ··························································································································· 11
2.6 Instantaneous Overcurrent ············································································································· 12
2.7 Time Ground OverVoltage ··········································································································· 12
2.8 Instantaneous Ground OverVoltage ······························································································ 13
2.9 Selective Ground Element ············································································································ 13
2.10 Output Contacts ··························································································································· 14
2.11 Insulation Test ······························································································································ 15
2.12 Mechanical Test ··························································································································· 15
2.13 Noise Test ···································································································································· 16
2.14 Temperature, Humidity Test ······································································································· 17
2.15 Other Operating Condition ·········································································································· 17
3. Protection Characteristics ···················································································································· 18
3.1 Overcurrent Function ····················································································································· 18
3.2 Ground OverVoltage Function ····································································································· 21
3.3 Selective Ground Function ············································································································ 22
4. Subsidiary Function ····························································································································· 23
4.1 Metering ·········································································································································· 23
4.2 Communication ······························································································································· 23
4.2.1 RS-232C Communication ······································································································· 24
4.2.2 RS-485C Communication ······································································································· 25
4.3 Self Diagnosis Function ················································································································ 25
4.4 Fault Recording Function ·············································································································· 26
5. Display Panel Construction ················································································································· 27
5.1 Front-side Display Panel Structure ······························································································ 27
5.2 Key Pad & Communication Connector ······················································································ 28

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5.3 LED ( Operating Indicators ) ······································································································ 28
6. Display & Setting Modes ··················································································································· 29
6.1 Key Operations and LCD Construction ······················································································ 29
6.1.1 LCD Default Display Condition, Backlight On/Off ··························································· 29
6.1.2 LCD Screen Display and Principles of Key Operation ····················································· 29
6.1.3 One-button Display ················································································································· 29
6.1.4 Menu-Tree ································································································································ 29
6.2 Setting Modes ································································································································ 30
6.2.1 Measurement Screen ··············································································································· 32
6.2.2 Protection Setting ···················································································································· 32
6.2.2.1 Protection ▶ Time OCR Setting ·················································································· 32
6.2.2.2 Protection ▶ INST. OCR Setting ················································································· 33
6.2.2.3 Protection ▶ Time OVGR Setting ··············································································· 34
6.2.2.4 Protection ▶ INST. OVGR Setting ·············································································· 34
6.2.2.5 Protection ▶ SGR Set Setting ······················································································ 35
6.2.3 Self-Diagnosis Screen ············································································································· 36
6.2.4 RS-485 Comm. Setting ·········································································································· 36
6.2.5 System Config. Setting ·········································································································· 37
6.2.5.1 System Config. ▶ Power system Setting ···································································· 37
6.2.5.2 System Config. ▶ T/S Output Setting ········································································ 38
6.2.5.3 System Config. ▶ Password Setting ············································································ 40
6.2.6 Recorder ··································································································································· 41
6.2.6.1 Recorder ▶ 1.Display Fault Screen ············································································· 41
6.2.6.2 Recorder ▶ 2.Clear Fault Category ············································································· 42
6.2.7 Test ··········································································································································· 42
6.2.7.1 Test ▶ Display Test ······································································································ 42
6.2.7.2 Test ▶ Contact Test ······································································································ 43
7. PC Software ( SetGDRSeries ) ········································································································· 45
7.1 Program Menu ······························································································································· 46
7.2 Device Selecting ···························································································································· 47
7.3 Communication Port Configuration ······························································································ 47
7.4 Setting Value Change Screen ······································································································· 48
7.4.1 Setting ······································································································································ 48
7.4.2 Status ······································································································································ 49
7.4.3 Report ······································································································································· 51
7.5 Help ················································································································································· 52

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Order of Table
【Table 2.1】 Input Current ··················································································································· 10
【Table 2.2】 Rated Control Source Voltage ······················································································ 10
【Table 2.3】 Case ·································································································································· 11
【Table 2.4】 Time Overcurrent Element ···························································································· 11
【Table 2.5】 Instantaneous Overcurrent Element ··············································································· 12
【Table 2.6】 Time Ground OverVoltage Element ············································································· 12
【Table 2.7】 Instantaneous Ground OverVoltage Element ······························································· 13
【Table 2.8】 Selective Ground Element ····························································································· 13
【Table 2.9】 Output Contacts / Capacity ··························································································· 14
【Table 2.10】 Insulation ························································································································ 15
【Table 2.11】 Vibration, Shock, Earthquake ······················································································ 16
【Table 2.12】 Noise Endurance ··········································································································· 16
【Table 2.13】 Temperature, Humidity ································································································· 17
【Table 2.14】 Other Usage Conditions ······························································································· 17
【Table 3.1】 Relay Time Characteristics and Characteristic Values for Curve Selection ············ 19
【Table 4.1】 Metering ··························································································································· 23
【Table 4.2】 Communication Method ································································································· 24
【Table 5.1】 Key Pad & Communication Connector ······································································· 28
【Table 5.2】 LED ( Operating Indicators ) ······················································································· 28
【Table 6.1】 Time OCR Menu ··········································································································· 33
【Table 6.2】 INST. OCR Menu ·········································································································· 34
【Table 6.3】 Time OVGR Menu ········································································································ 34
【Table 6.4】 INST. OVGR Menu ······································································································· 35
【Table 6.5】 SGR Menu ······················································································································ 36
【Table 6.6】 RS-485 Comm. Setting ·································································································· 37
【Table 6.7】 T/S Connection Menus ·································································································· 39
【Table 6.8】 Setting Menus ················································································································· 44
【Table 7.1】 SetGDRSeries Program Menus ······················································································ 46
【Table 7.2】 Communication Port Configuration ··············································································· 48
Appendix 1. Product Factory Default Setting Values ········································································ 53

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Order of Figures and Diagrams
【Figure 3.1】 INST. OCR(IOCR) Logic Diagram ············································································ 19
【Figure 3.2】 Time OCR(TOCR) Logic Diagram ············································································· 20
【Figure 3.3】 INST. OVGR(IOVGR) Logic Diagram ······································································ 21
【Figure 3.4】 TIME OVGR(TOVGR) Logic Diagram ····································································· 21
【Figure 3.5】 SGR Logic Diagram ····································································································· 22
【Figure 4.1】 RS-232C Circuit Diagram ···························································································· 24
【Figure 4.2】 RS-232C Connection ····································································································· 24
【Figure 4.3】 RS-485C Line Connection Diagram ············································································ 25
【Figure 5.1】 Front Panel Display ······································································································ 27
【Figure 6.1】 Menu Tree ····················································································································· 30
【Figure 7.1】 SetGDRSeries Default Screen ······················································································ 45
【Figure 7.2】 Relay Selecting ·············································································································· 47
【Figure 7.3】 Communication Port Setting ························································································ 47
【Figure 7.4】 GDR-AEF01 Setting ····································································································· 49
【Figure 7.5】 GDR-AEF01 Status ······································································································· 50
【Figure 7.6】 GDR-AEF01 Report ···································································································· 51
【Figure 7.7】 Help ································································································································ 52
Appended 1. Dimensioned Drawings Unit : mm ············································································· 54
Appended 2. Internal Block Diagram ·································································································· 55
Appended 3. External Connection Diagram ························································································ 55
Appended 4. Inverse Time Characteristic Curve ················································································ 56
Appended 5. Very Inverse Time Characteristic Curve ······································································ 57
Appended 6. Extremely Inverse Time Characteristic Curve ····························································· 58
Appended 7. Long Inverse Time Characteristic Curve ······································································ 59
Appended 8. Kyongbo Induction Type Inverse Time(KEPCO Type) Characteristic Curve ·········· 60
Appended 9. Kyongbo Induction Type Very Inverse Time(KEPCO Type) Characteristic Curve ······ 61
Appended 10. Overcurrent Definite Time Characteristic Curve ······················································· 62
Appended 11. Ground Overcurrent Element Inverse Time Characteristic Curve ··························· 63
Appended 12. Ground Overvoltage Element Definite Time Characteristic Curve ························· 64
Appended 13. Selective Ground Element Inverse Time Characteristic Curve ································ 65
Appended 14. Selective Ground Element Definite Time Characteristic Curve ······························ 66
Appended 15. Selective Ground Element Operation Characteristic Curve ······································ 67

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1. General Features
This Relay contains Relay elements of OCRx2, OVGRx1, and SGRx1 at the same
time, and is a Digital arithmetic relay designed and manufactured appropriately
applicable to protect the equipment and electrical lines by detecting and blocking the
circuit or alarming when an accident caused by non-ground system or short circuit in
resistance ground system or overcurrent by overload or grounding accident between
electrical cable and the grounding accident caused by insulation heating of electrical
equipment or destruction, so it is not just easy to change the operation time and
operation current, but it can also record and store fault information thereby greatly
enhancing the reliability of the cable line, and the main characteristics are as follows.
Features
▣ Total arithmetic type over-current, ground overvoltage, and selective ground Relay.
▣ Variety of timing characteristics
- OCR : 7 time characteristics included
- OVGR : instantaneous, inverse, definite time characteristics included
- SGR : inverse and definite time characteristics included
▣ Duration of maintaining output contact is 0.00 ~ 60.00Sec (0.01Sec Step), and
variable setting is possible.
▣ Set value and measured values are Displayed digitally through LCD Screen. (4 x
20 LCD Screen)
▣ Enhance reliability with surveillance function at all times.
▣ Free selection of frequency Settings according to the rated frequency of the line.
(50 / 60Hz)
▣ Possible to set each of 7 Relay contact output (T/S Output) to 12 modes, and all
of these can be used for Alarms.
- contact for Trip(1a), contact for Signal(6a)
▣ Reliability is increased by the operation through output contacts when the Relay is
in abnormal state.
▣ Convenient PC Applications
- SetGDRSeries : change setting values, verify the measurements, verify Fault
information, display status, Remote Reset.
▣ Possible to self-test through manual Trip command(Contact Test)
▣ Maintains thorough security using password input when changing setting values
▣ Various communications supported
- Communication Methods : RS-232C, RS-485C (SCADA communications)

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- Supported Protocol : MODBUS
▣ Increased EMC / EMI performance
▣ Applied Standard : Korea Electrical Manufacturers' Cooperative Standard
(KEMC1120)
2. Technical Data
2.1 Voltage, Current Input
Rated Zero
Sequence
Voltage
VO
AC 190V
Rated Current
(IN)
IN
AC 5A
IO
AC 1.5mA
Overload
Endurance
VO
1.15 time the rated voltage / 3 hours
IN
2 time the rated current / 3 hours
20 times the rated current / 2 seconds
IO
100 times the rated current / continuously
Burden
0.5VA or less / Phase
【Table 2.1】 Input Current
2.2 Rated Control Source Voltage
Rated Current (IN)
AC/DC 110 ~ 220V (free voltage)
Overload Endurance
1.3 times rated voltage / 3 hours
Burden
Always
30W or less
Operation
70W or less
【Table 2.2】 Rated Control Power
2.3 Rated Frequency
50Hz or 60Hz (Sine Waveform)

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2.4 Case
Case Structure
Flushed Drawer Type
Case Color
Munsell No. N1.5 (Black)
Case Material
Fe (Steel)
【Table 2.3】 Case
2.5 Time Overcurrent
Operation Value
2.0 ~ 12.5A (0.1A Step)
Operation Time
Characteristics
Inverse Time , Very Inverse Time , Extreme
Inverse Time , Long Inverse Time
Kyongbo Induction Type (KEPCO Type)
Inverse Time ,
Kyongbo Induction Type (KEPCO Type) Very
Inverse Time , Definite Time
Operation Time Ratio
0.1 ~ 10.0 (0.1 Step)
Definite Time
Operation Time
0.04 ~ 60.00Sec (0.01Sec Step)
Release Delay Time
0.00 ~ 60.00Sec (0.01Sec Step)
Release Value
At least 95% of the Setting Value
Operation Value
Precision Ratio
Within ±5% of the Setting Value
【Table 2.4】 Time Overcurrent Element

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2.6 Instantaneous Overcurrent
Operation Value
10 ~ 90A (1A Step)
Operation Time
Characteristics
Instantaneous Time ( ≤ 40ms ), Definite Time
Definite Time
Operation Time
0.04 ~ 60.00Sec (0.01Sec Step)
Release Delay Time
0.00 ~ 60.00Sec (0.01Sec Step)
Release Value
At least 95% of the Setting Value
Operation Value
Precision Ratio
Within ±5% of the Setting Value
【Table 2.5】 Instantaneous Overcurrent Element
2.7 Time Ground OverVoltage
Operation Value
5 ~ 100V (1V Step)
Operation Time
Characteristics
Inverse Time , Definite Time
Operation Time Ratio
0.1 ~ 10.0 (0.1 Step)
Definite Time
Operation Time
0.04 ~ 60.00Sec (0.01Sec Step)
Release Delay Time
0.00 ~ 60.00Sec (0.01Sec Step)
Release Value
At least 95% of the Setting Value
Operation Value
Precision Ratio
Within ±5% of the Setting Value
【Table 2.6】 Time Ground OverVoltage Element

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2.8 Instantaneous Ground OverVoltage
Operation Value
110 ~ 160V (1V Step)
Operation Time
Characteristics
Instantaneous Time ( ≤ 40ms ), Definite Time
Definite Time
Operation Time
0.04 ~ 60.00Sec (0.01Sec Step)
Release Delay Time
0.00 ~ 60.00Sec (0.01Sec Step)
Release Value
At least 95% of the Setting Value
Operation Value
Precision Ratio
Within ±5% of the Setting Value
【Table 2.7】 Instantaneous Ground OverVoltage Element
2.9 Selective Ground Element
Operation Current
0.9 ~ 10mA (0.1mA Step)
Operation Voltage
5 ~ 100V (1V Step)
Base Phase Angle
0˚ ~ 60˚ (1˚ Step)
Operation Phase Angle
± 90˚ of the Base Phase Angle
Operation Time
Characteristic
Definite Time, Inverse Time
Operation Time Ratio
0.1 ~ 10.0 (0.1 Step)
Definite Time Operation
Time
0.04 ~ 60.00Sec (0.01Sec Step)
Release Delay Time
0.00 ~ 60.00Sec (0.01Sec Step)
Release Value
At least 95% of the Setting Value
Operation Value
Precision Ratio
Within ±5% of the Setting Value
【Table 2.8】 Selective Ground Element

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T / S1 contacts (Trip contacts) - 1a Contact
Rated Voltage
AC 250V, DC 125V
Continuous Flow
Electricity Capacity
20A (AC 250V)
0.5 sec. Close
Circuit Capacity
30A (DC 125V)
Closing Capacity
6250VA
Material
Silver alloy
T / S2 ~ T / S7 Contacts (Signal contacts) - 6a Contact
Rated Voltage
AC 250V, DC 125V
Continuous Flow
Electricity Capacity
5A (AC 250V)
0.5 sec. Close
Circuit Capacity
5A (DC 125V)
Closing Capacity
1250VA / 150W
Material
Gold-plate silver alloy
Healthy Alarm - 1b Contact
Rated Voltage
AC 250V, DC 125V
Continuous Flow
Electricity Capacity
10A (AC 250V)
Open Circuit
Capacity
DC 125V, 30W, Correction Number(25ms), 1A
Closing Capacity
2500VA / 300W
Material
Silver alloy
【Table 2.9】 Output Contacts / Capacity
2.10 Output Contacts / Capacity

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2.11 Insulation Test
Insulation
Resistance
DC 500V
Electric Circuit to
Ground
10MΩ
IEC60255-5
Between Electric
Circuits
5MΩ
Between Electric
Circuit Connections
Commercial
Frequency
Withstand
Voltage
50/60Hz,
1min
Electric Circuit
Bundle to Ground
2kV
IEC60255-5
Between Electric
Circuits
Between Connection
Circuit Contacts
1kV
Impulse
Withstand
Voltage
1.2/50μs,
3 times each
for
positive/negative
polarity
Electric Circuit
Bundle to Ground
5kV
IEC60255-5
Between
Transformer Circuits
Between Transformer
Control Circuits
Between Control
Circuits
3kV
Between Tranformer
Circuit Contacts
Between Control
Power Circuit
Contacts
【Table 2.10】 Insulation
Caution) AUX POWER and 485 Communication Circuits enclose surge protection
circuit inside the relay, so do not test insulation resistance test and withstand
voltage test.

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2.12 Mechanical Test
Vibration
Vibration
Response Test
10 ~ 150Hz, 0.5G, Front/Back, Left/Right, Up/Down
1 time
Vibration
Endurance Test
10 ~ 150Hz, 1G, Front/Back, Left/Right, Up/Down
20 times
Shock
Shock Response
Test
5G, Front/Back, Left/Right, Up/Down
3 times
Shock Withstand
Test
15G, Front/Back, Left/Right, Up/Down
3 times
Bump Test
10G, Front/Back, Left/Right, Up/Down
100 times
Earthquake
1 ~ 8㎐
x : 3.5mm, y : 1.5mm, Sweep : 1 time
8 ~ 35㎐
x : 1g, y : 0.5g, Sweep : 1 time
【Table 2.11】 Vibration, Shock, Earthquake
2.13 Noise Test
1MHz burst disturbance
1MHz, 75ns,
400Hz, 2Sec
Common
mode
2.5kV
IEC60255-22-1
Differential
mode
1.0kV
EFT Burst
Applied Voltage
4kV
IEC60255-22-4
Repeated
Frequency
2.5kHz
Electrostatic Discharge
Air discharge
8kV
IEC60255-22-2
Contact discharge
6kV
Surge Electrical
Disturbance
1.2/50μs, 8/20μs,
30sec, 3 times
Common
mode
2.0kV
IEC60255-22-5
Differential
mode
1.0kV
Radio Frequency
Radiation Endurance
80MHz ~ 1GHz, 10V/m, 1sec
IEC60255-22-3
Radio Frequency
Conduction Endurance
150kHz ~ 80MHz, 10V/m, 1sec
IEC60255-22-6
【Table 2.12】 Noise Endurance

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2.14 Temperature, Humidity Test
Temperature Range
Operation Assurance
-10℃ ~ +55℃
Recovery Assurance
-20℃ ~ +60℃
Relative Humidity
Daily Average 30% ~ 90%
【Table 2.13】 Temperature, Humidity
2.15 Other Operating Condition
Surface Height
1000m or less
Condition where there is no abnormal vibration, shock, slope or influence
of the magnetic field
Place where there is no explosive dust, flammable dust, or flammable
/ rusty gas, or salt
【Table 2.14】 Other Operating Conditions

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3. Protection Characteristics
3.1 Overcurrent Function
This relay contains the Instantaneous Time characteristic, Inverse Time
characteristic, and Definite Time characteristic to be used for overcurrent and short
circuit protection. GDR-AEF01 marks the instantaneous overcurrent element as
INST.OCR(IOCR), and the time overcurrent element as Time OCR(TOCR).
The instantaneous time characteristic is a function to output Trip signal immediately
when a current over the setting value is input, the Trip time is less than 40ms, and
the inverse time characteristic is a function between the current and the time, and the
operation time is shorter as the current is bigger. There are 4 international
standard(IEC) inverse time characteristics and 2 KEPCO type inverse time
characteristics equipped.
When applying the inverse time characteristics, select one from the 6 characteristics.
4 Inverse characteristics following the international standard(IEC255-4), and the time
and current relationship function of 2 KEPCO type characteristics are as follows.










×



sec
T = Operation Time, K and C = Relay characteristic value
I = Relay input current / Relay operation setting value
L = Characteristic curve index, M = Operation time ratio

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Time Characteristic
Characteristic Value
Indication
Mark
Note
K
L
C
Inverse Time
0.14
0.02
0
NI
-
Kyongbo Induction
Type Inverse Time
0.11
0.02
0.42
KNI
KEPCO
Type
Very Inverse Time
13.5
1
0
VI
-
Kyongbo Induction
Type Very Inverse
Time
39.85
1.95
1.084
KVI
KEPCO
Type
Extreme Inverse
Time
80
2
0
EI
-
Long Inverse Time
54
1
0
LI
-
Definite Time
-
-
-
DT
-
【Table 3.1】 Relay Time Characteristics and Characteristic Values for Curve Selection
When setting the relay, selecting the time characteristic curve will decide the K,
L, C values in the above table.
Logic Diagram for overcurrent element operation is as follows.
【Figure 3.10】 INST. OCR(IOCR) Logic Diagram

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【Figure 3.11】 Time OCR(TOCR) Logic Diagram