Kyongbo Electric GDR-M02 User manual

Digital Motor Protection Relay (GDR-M02) User's Manual (V1.00)
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KyongBo Electric Co.,Ltd
Digital Motor Protection Relay User's Manual
TYPE : GDR-M02
2010. 04. 12
Version 1.00
Kyongbo Electric Co., Ltd.

Digital Motor Protection Relay (GDR-M02) User's Manual (V1.00)
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KyongBo Electric Co.,Ltd
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
1. General Features ················································································································· 10
2. Technical Data ······················································································································ 12
2.1 Voltage, Current Input ································································································· 12
2.2 Rated Control Source Voltage ···················································································· 12
2.3 Rated Frequency ··········································································································· 12
2.4 Case ································································································································ 12
2.5 Time OverCurrent Element ························································································· 13
2.6 Instantaneous OverCurrent Element ············································································ 13
2.7 Time Ground OverCurrent Element ··········································································· 14
2.8 Instantaneous Ground OverCurrent Element ······························································ 14
2.9 OverVoltage Element ··································································································· 15
2.10 UnderVoltage Element ································································································· 15
2.11 Reverse Phase Element ································································································ 15
2.12 Negative-Sequence Current Element ··········································································· 16
2.13 Output Contacts ············································································································16
2.14 Insulation Test ··············································································································· 17
2.15 Mechanical Test ············································································································18
2.16 Noise Test ····················································································································· 18
2.17 Temperature, Humidity Test ························································································ 19
2.18 EMI : ElectroMagnetic Interference ··········································································· 19
2.19 Other Operating Condition ·························································································· 19
3. Protection Characteristics ····································································································· 20
3.1 OverCurrent Function ··································································································· 20
3.2 Ground OverCurrent Function ····················································································· 23
3.3 OverVoltage Function ··································································································· 24
3.4 UnderVoltage Function ································································································· 25
3.5 Negative-Sequence Current Function ·········································································· 27
3.6 Reverse Phase Function ······························································································· 28

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4. Subsidiary Function ·············································································································· 29
4.1 Metering ··························································································································· 29
4.2 Communication ················································································································ 29
4.2.1 RS-232C Communication ························································································ 29
4.2.2 RS-485C Communication ························································································ 30
4.3 Self Diagnosis Function ································································································· 31
4.4 Fault Recording Function ······························································································ 31
5. Display Panel Construction ································································································· 32
5.1 Front-side Display Panel Structure ··············································································· 32
5.2 Key Pad & Communication Connector ······································································· 33
5.3 LED ( Operating Indicators ) ······················································································· 33
6. Display & Setting Modes ··································································································· 34
6.1 Key Operations and LCD Construction ······································································· 34
6.1.1 LCD Default Display Condition, Backlight On/Off ·········································· 34
6.1.2 LCD Screen Display and Principles of Key Operation ···································· 34
6.1.3 One-button Display ································································································ 34
6.1.4 Menu-Tree ··············································································································· 34
6.1.5 Setting Modes ········································································································· 35
6.1.6 Measurement Screen ······························································································ 37
6.1.7 Protection Setting ··································································································· 37
6.1.8 Self-Diagnosis Screen ···························································································· 43
6.1.9 RS-485 Comm. Setting ························································································· 44
6.1.10 System Config. Setting ·························································································· 45
6.1.11 Recorder ·················································································································· 48
6.1.12 Test ·························································································································· 49
7. PC Software ·························································································································· 53
7.1 Program Menu ················································································································54
7.2 Communication Port Configuration ··············································································· 55
7.3 Setting Value Change Screen ······················································································· 56
7.3.1 Setting ······················································································································· 56
7.3.2 Status ······················································································································· 57
7.3.3 Report ························································································································ 58
7.4 Help ·································································································································· 59

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Order of Table
【Table 2.1】 Input Voltage ································································································· 12
【Table 2.2】 Rated Control Power ···················································································· 12
【Table 2.3】 Case ················································································································ 12
【Table 2.4】 Time OverCurrent Element ·········································································· 13
【Table 2.5】 Instantaneous OverCurrent Element ···························································· 13
【Table 2.6】 Time Ground OverCurrent Element ···························································· 14
【Table 2.7】 Instantaneous Ground OverCurrent Element ·············································· 14
【Table 2.8】 OverVoltage Element ···················································································· 15
【Table 2.9】 UnderVoltage Element ·················································································· 15
【Table 2.10】 Voltage Reverse Phase Element ·································································· 15
【Table 2.11】 Negative-Sequence Current Function ·························································· 16
【Table 2.12】 Output Contacts / Capacity ·········································································· 16
【Table 2.13】 Insulation Test ······························································································· 17
【Table 2.14】 Mechanical Test ···························································································· 18
【Table 2.15】 Noise Test ······································································································ 18
【Table 2.16】 Temperature, Humidity Test ········································································ 19
【Table 2.17】 EMI : ElectroMagnetic Interference ···························································· 19
【Table 2.18】 Other Operating Condition ··········································································· 19
【Table 3.1】 Time Curve Characteristic ············································································ 21
【Table 4.1】 Measurement Function ·················································································· 29
【Table 4.2】 Communication Method ················································································ 30
【Table 5.1】 Key Pad & Communication Connector ······················································ 33
【Table 5.2】 LED ( Operating Indicators ) ······································································ 33
【Table 6.1】 Time OCR Menu ·························································································· 38
【Table 6.2】 INST. OCR Menu ························································································· 39
【Table 6.3】 Time OCGR Menu ······················································································· 39
【Table 6.4】 INST. OCGR Menu ······················································································ 40
【Table 6.5】 OVR Menu ···································································································· 41
【Table 6.6】 UVR Menu ···································································································· 42
【Table 6.7】 NSOCR Menu ······························································································· 42
【Table 6.8】 RPR Menu ····································································································· 43
【Table 6.9】 RS-485 Comm. Setting ················································································· 44
【Table 6.10】 T/S Connection Menus ················································································· 46
【Table 6.11】 Setting Menus ································································································ 51
【Table 7.1】 GDR-M02 Program Menus ·········································································· 54
【Table 7.2】 Communication Port Configuration ····························································· 55

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Order of Figures
【Figure 3.1】 INST. OCR(IOCR) Logic Diagram ····························································· 21
【Figure 3.2】 Time OCR(TOCR) Logic Diagram ····························································· 22
【Figure 3.3】 INST. OCGR(IOCGR) Logic Diagram ······················································· 23
【Figure 3.4】 Time OCGR(TOCGR) Logic Diagram ························································ 23
【Figure 3.5】 OVR Logic Diagram ( 1 Phase ) ······························································· 24
【Figure 3.6】 OVR Logic Diagram ( 3 Phases ) ····························································· 25
【Figure 3.7】 UVR Logic Diagram ( 1 Phase ) ······························································· 26
【Figure 3.8】 UVR Logic Diagram ( 3 Phases ) ····························································· 26
【Figure 3.9】 NSOCR Logic Diagram ················································································ 27
【Figure 3.10】RPR Logic Diagram ······················································································ 28
【Figure 4.1】 RS-232C Circuit Diagram ············································································· 30
【Figure 4.2】 RS-232C Connection ····················································································· 30
【Figure 4.3】 RS-485C Connection Diagram ····································································· 31
【Figure 5.1】 Front Panel Display ······················································································· 32
【Figure 6.1】 Menu Tree ······································································································ 35
【Figure 7.1】 GDR-M02 Default Screen ············································································ 53
【Figure 7.2】 Communication Port Setting ········································································· 55
【Figure 7.3】 GDR-M02 Setting ·························································································· 56
【Figure 7.4】 GDR-M02 Status ···························································································· 57
【Figure 7.5】 GDR-M02 Report ·························································································· 58
【Figure 7.6】 Help ··············································································································· 59
Appendix 1. Setting Value at Product Shipping ································································· 60

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Order of Diagram
Appended 1. Dimensioned Drawings Unit : mm ····························································· 62
Appended 2. Internal Block Diagram ··················································································· 63
Appended 3. External Connection Diagram ········································································· 63
Appended 4. Over current, Ground Over Current Element NI Characteristic Curve ········ 64
Appended 5. Over current, Ground Over Current Element VI Characteristic Curve ········ 65
Appended 6. Over current, Ground Over Current Element EI Characteristic Curve ········ 66
Appended 7. Over current, Ground Over Current Element LI Characteristic Curve ········ 67
App en de d 8. Over Current, Ground Over Current Element KNI(KEPCO Type) Characteristic Curve · · · · 68
App en de d 9. Over Current, Ground Over Current Element KVI(KEPCO Type) Characteristic Curve · · · · 69
Appended 10. Over Current, Ground Over Current Element KLNI(KEPCO Type) Characteristic Curve · · 70
Appended 11. Over Current, Ground Over Current Element KLVI(KEPCO Type) Characteristic Curve · · 71
Appended 12. Over current, Ground Over Current Element DT Characteristic Curve ······· 72
Appended 13. Over Voltage Element NI Characteristic Curve ·········································· 73
Appended 14. Over Voltage Element DT Characteristic Curve ········································· 74
Appended 15. Under Voltage Element NI Characteristic Curve ········································ 75
Appended 16. Under Voltage Element DT Characteristic Curve ······································· 76

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1. General Features
This Relay contains Relay elements of 50/51×3, 50/51N×1, 47×1, 46×1, 59×3, 27×3
at the same time, and is a Digital arithmetic relay designed and manufactured properly
for the protection when fault occurred such as overcurrent, ground overcurrent,
overvoltage, undervoltage, negative-sequence current, reverse phase etc. from directing
grounding system or high load grounding system using 3phase motor. And it is not just
easy to change the operation time and operation current, voltage 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 over-current, & over/under voltage &
negative-sequence current Relay.
▣ Variety of time characteristic curve
- OCR / OCGR : 10 time characteristic curve enclosed
- OVR : Inverse time, Definite Time Characteristic curve enclosed
- UVR : Reverse Inverse time, Definite time characteristic curve enclosed
- NSOCR : Definite time characteristic curve enclosed
- RPR : Definite time characteristic curve enclosed
▣ 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 4 Relay contact output (T/S Output) to 17 modes, and all
of these can be used for Alarms.
- contact for Trip(1a), contact for Signal(3a)
▣ Reliability is increased by the operation through output contacts when the Relay is
in abnormal state.
▣ Convenient PC Applications
- 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

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▣ Various communications supported
- Communication Methods : RS-232C, RS-485C (SCADA communications)
- Supported Protocol : MODBUS
▣ Enhanced EMC / EMI performance
▣ Applied Standard : Korea Electrical Manufacturers' Cooperative Standard
(KEMC1120)

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2. Technical Data
2.1 Voltage, Current Input
Rated Voltage AC 110V
Rated Current AC 5A
Overload Endurance
Voltage 1.15 times rated voltage / 3 hours
Current 2 times rated current / 3 hours
20 times rated current / 2 seconds
Burden 0.5VA or less / Phase
【Table 2.1】 Input Current
2.2 Rated Control Power
Rated Control Power AC/DC 110 ~ 220V (free voltage)
Overload Endurance 1.3 times rated voltage / 3 hours
Burden
A l w a y s 30W or less
operation 70W or less
【Table 2.2】 Rated Control Power
2.3 Rated Frequency
50Hz or 60Hz (Sine Waveform )
2.4 Case
Case Structure Flushed Drawer Type
Case Color Munsell No. N1.5 (Black)
Case Material Fe (steel)
【Table 2.3】 Case

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2.5 Time OverCurrent Element
Operation Value 2.0 ~ 12.5A (0.1A Step)
Operation Time
Characteristics
Inverse Time NI
0.1 ~ 10.0
(0.1 Step)
Inverse Time
(KEPCO Type) KNI
Very Inverse Time VI
Very Inverse Time
(KEPCO Type) KVI
Extreme Inverse Time EI
Long Inverse Time LI
Long Inverse Time
(KEPCO Type) KLNI
Long Very Inverse
Time (KEPCO Type) KLVI
Definite Time DT 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 Ration Within ±5% of the Setting Value
【Table 2.4】 Time Over Current Element
2.6 Instantaneous OverCurrent Element
Operation Value 10 ~ 90A (1A Step)
Operation Time
Characteristics
Instantaneous
Time 40ms
Definite 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 Over Current Element

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2.7 Time Ground Overcurrent
Operation Value 0.2 ~ 2.5A (0.1A Step)
Operation Time
Characteristics
Inverse Time NI
0.1 ~ 10.0
(0.1 Step)
Inverse Time
(KEPCO Type) KNI
Very Inverse Time VI
Very Inverse Time
(KEPCO Type) KVI
Extreme Inverse Time EI
Long Inverse Time LI
Long Inverse Time
(KEPCO Type) KLNI
Long Very Inverse
Time (KEPCO Type) KLVI
Definite Time DT 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 Over Current Element
2.8 Instantaneous Ground Over Current Element
Operation Value 2 ~ 50A (1A Step)
Operation Time
Characteristic
Instantaneous
Time 40ms
Definite 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 Overcurrent Element

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2.9 Over Voltage Element
Operation Value 65 ~ 170V (1V Step)
Operation Time
Characteristics
Inverse Time 0.1 ~ 10.0 (0.1 Step)
Definite 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】 Over Votlage Element
2.10 Under Voltage Element
Operation Value 30 ~ 105V (1V Step)
Operation Time
Characteristics
Reverse
Inverse Time 0.1 ~ 10.0 (0.1 Step)
Definite 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 2.9】 Under Voltage Element
2.11 Reverse Phase Element
Operation Value When reverse phase from more than 40% o
f
rated volta
g
e
Operation Time
Characteristics
Definite
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 2.10】 Reverse Phase Element

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2.12 Negative-Sequence Current Element
Operation Value Negative-Sequence 30 ~ 70% (1% step)
Operation Time
Characteristics
Definite
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 2.11】 Negative-Sequence Current Element
2.13 Output Contacts
T / S1 Contacts (Trip contact) - 1a Contacts
Rated Voltage AC 250V, DC 125V
Continuous Flow
Electricity Capacity 10A (AC 250V)
0.3 sec. Close
Circuit Capacity 30A (DC 125V)
Closing Capacity 6250VA
Material Silver alloy
T / S2 ~ T / S4 Contacts (Signal contacts) - 3a Contacts
Rated Voltage AC 250V, DC 125V
Continuous Flow
Electricity Capacity 5A (AC 250V)
0.3 sec. Close
Circuit Capacity 5A (DC 125V)
Closing Capacity 1250VA / 150W
Material Gold-plate silver alloy
Healthy Alarm - 1b Contacts
Rated Voltage AC 250V, DC 125V
Continuous Flow
Electricity Capacity 1A (AC 250V)
Open Circuit Capacity DC 125V, 30W, Time constant(25ms), 1A
Closing Capacity 2500VA / 300W
Material Silver alloy
【Table 2.12】 Output Contacts / Capacity

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2.14 Insulation Test
Insulation
Resistance DC 500V
Electric Circuit to
Ground 10M
IEC60255-5
Between Electric
Circuits 5M
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
1.2/50s,
3 times
each for
positive/neg
ative
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 2.13】 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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2.15 Mechanical Test
Vibration
Vibration Response 10 ~ 150Hz, 0.5G, Front/Back, Left/Right,
Up/Down 1 time
Vibration Endurance 10 ~ 150Hz, 1G, Front/Back, Left/Right,
Up/Down 20 times
Shock
Shock Response 5G, Front/Back, Left/Right, Up/Down
3 times
Shock Withstand 15G, Front/Back, Left/Right, Up/Down
3 times
Bump 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 2.14】 Mechanical Test
2.16 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
Lighting Surge 1.2/50s, 8/20s,
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 2.15】 Noise Test

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2.17 Temperature, Humidity Test
Temperature Range
Operation Assurance -10℃ ~ +55℃
Recovery Assurance -20℃ ~ +60℃
Relative Humidity Daily Average 30% ~ 90%
【Table 2.16】 Temperature, Humidity Test
2.18 EMI : ElectroMagnetic Interference
Noise
Terminal
Voltage
Frequency (MHz) Quasi-peak Average
0.15 ~ 0.5 79 66
0.5 ~ 30 73 60
Noise Field
Strength
Frequency (MHz) Quasi-peak Limit value
(㏈㎶/m)
30 ~ 230 50.5
230 ~ 1,000 57.5
【Table 2.17】 ElectriMagnetic Interference
2.19 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 2.18】 Other Operating Condition

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3. Protection Characteristics
3.1 OverCurrent Function
This relay contains the Instantaneous Time characteristic and Time Characteristics of
9 to be used for overcurrent and short circuit protection. GDR-M02 marks the
instantaneous element as INST.OCR(IOCR), and the time over current element as Time
OCR(TOCR), time characteristics curve type is as follow 【Table 3.1】
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 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 4 KEPCO type inverse time
characteristics equipped.
When applying the inverse time characteristics, select one from the 9 characteristics.
(Definite time included)
4 Inverse characteristics following the international standard(IEC255-4), and the time
and current relationship function of 4 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