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Figure 4-2 LCD Menu Tree Diagram of FTU-R200

4.2.1.1 INITIAL DISPLAY

[Initial Display] shows up the reclosing status.

< R / C f o r D A S >

S e q u e n c e : 0 [ H O ] R / C S t a t u s : C L O S E [ H O ME ]

Figure 4-3 Initial Display

MENU button at [Initial Display] goes to [Main Menu Display]. MENU button toggles between [Initial Display] and [Main Menu Display].

UP or DOWN button at [Initial Display] goes to [Current / Voltage Measurement Display]. UP / DOWN button toggles between [Initial Display] and [Current / Voltage Measurement Display].

www.jinkwang.co.kr 31 / 111 Total Reclosing Shot 3 Times 0[HO], 1~3[SR], 4[LO]

9 HO Home

Diagnosis Fail If diagnosis failure happens, [FAIL] message will appear in the right side of [HOME] or <ABC.RST> down the main menu trees. ‘>’ symbol indicates the cursor position and ENTER button enters into the selected main menu’s sub items.

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In Function Setting, there are 4 different setting groups and the different setting values can be stored individually in 4 different setting groups.

After finishing the set value change, when MENU button is pushed to return to [Main Menu Display], [Set Value Change Save Display] shows up to determine Yes or No. If selecting yes and pushing ENTER button, the changed set values are all saved. However, if selecting No and ENTER button or MENU button again, the changed set values are not saved and the existing set values are still applied.

9 CAUTION: Be careful not to push down MENU buttons repeatedly! Then, the newly changed set values are neither saved nor applied.

Function Setting Group1, Group2, Group3, Group4, Group Setting Configuration I/O, Communication, Event, Time

Display Measurements, Status, Counter

Event List I/O events, Function events, System events, Fault I events, Demand I events, Demand P events, Demand Q events, Max. I events, Max. P events, Max. Q events

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Configuration menu has the setting items for communication, I/O, and system configuration.

Setting items are I/O, Communication, Event and Time.

After finishing the set value change, when MENU button is pushed to return to [Main Menu Display], [Set Value Change Save Display] shows up to determine Yes or No. If selecting yes and pushing ENTER button, the changed set values are all saved. However, if selecting No and ENTER button or MENU button again, the changed set values are not saved and the existing set values are still applied.

9 CAUTION: Be careful not to push down MENU buttons repeatedly! Then, the newly changed set values are neither saved nor applied.

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In Display menu, measurement values, monitored status, and counter values are displayed.

4.2.1.6 EVENT LIST

In Event List menu, all types of events are displayed with occurred time and event description.

Using UP & DOWN buttons, event list can be scrolled up and down in the LCD display.

Event List Sub Items Max.

I/O Events Status change of binary Input/Output 1023

Function Events Operated status of Protection Function 1023

System Events Setting change, Reset, Self Dignosis 255

Fault I Events Latest fault current, phase and time 255 Demand I,P,Q Events Each phase daily average load current, active power

and reactive powe with time

1023

Max. I,P,Q Events Each phase daily Peak load current, active power and reactive powe with time

1023

www.jinkwang.co.kr 35 / 111 5. PROTECTION FUNCTIONS

5.1. FAULT DETECTION

FTU detects the Phase & Earth Fault and trip the breaker.

The fastest operation time is within 45msec including auto-recloser operating time. There are 58 trip curves, which can be selected for fast and delayed operation respectively. The Curve can be edited by using several parameters, i.e. time multiplier, time adder and minimum response time.

And high current trip element can be used for instantaneous trip. It is definite time characteristics. During cold-load condition, pickup multiplied by cold-load multiplier. During the cold-load condition, time-delayed curve is applied instead of fast curve. This function can be enabled or disabled by cold-load multiplier.

Earth fault detection function can be enabled or disabled by ‘Ground Protection Enable’.

Phase Fault Earth Fault

RDMT/RIDMT RDMT RDMT/RIDMT RDMT RDMT(Definite Time)

RIDMT(Inverse Time) Reset Definite

Time 0.00~100.00 0.00 0.00~100.00 0.00 0.01 sec

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Reset Type RDMT/RIDMT RDMT RDMT/RIDMT RDMT RDMT(Definite Time)

RIDMT(Inverse Time) Reset Definite

Time

0.00~100.00 0.00 0.00~100.00 0.00 0.01 sec

5.1.1 Definite Time Protection

Definite Time is an alternative to Inverse Time Protection. It works by tripping the recloser at a fixed time after pick-up. spread-out, therefore HCT element should operate faster than Instantaneous or Time-Delayed TC curve’s operation time and its priority must be higher than the normal auto-reclosing sequence.

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In Single Shot Operation is used to provide an appropriate protection curve when non-reclosing operation is required, for example, when closing onto a fault.

In Single Shot Operation the controller goes directly to lockout after one trip and will not auto-reclosing.

Range Def. Step Unit Comment

Single Shot Time 0~180 10 1 sec

5.1.4 TC Curve

FTU-R200 has 54 types of built-in TC curves including ANSI, IEC Standard curves. And customer can define additional 4 curves as his own curves by using PC Software. Basically, built-in curves have inverse time characteristrics, but can be easily adjusted by three parameters such as multiplier, time adder and minimum response time. In engineering step, the selection and adjustments of TC curves shall be done for the protection coordination with other protection devices in the feeder.

The follwing parameters are related to change and editing of TC curve’s characteristics.

9 Time Multiplier

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9 Time Adder

9 Minimum Response Time

Time Multiplier is multiplied to the operating time of basic curve (TDM=1.0), then Time Adder is added to the resulting operating time of the curve adjusted by multiplier. Minimum Response Time defines the fastest operating time of the curve.

The following tables describe the built-in TC Curve Type and the corresponding numbers in the setting. TC Curve graphs are shown in the appendix.

Setting No. 1 2 3 4 5 6 7 8 9 10

IEC Standard Curve Standard Inverse(NI),Very Inverse(VI),Extremely Inverse(EI) Long-time Inverse(LI),Short-time Inverse(SI)

www.jinkwang.co.kr 39 / 111 9 IEC, ANSI/IEEE, US STANDARD TC CURVE EQUATION

T = TDM • {α / (Mβ - 1) +γ}

TRESET = TDM • {τ / (Mβ - 1)}

T : Operate Time, TDM : Multiplier Setting, TRESET : Reset Time

Curve Type Standard α β γ τ

Moderately Inverse(IM) 0.0515 0.02 0.114 4.85

Short-time Inverse(U2) CO2 0.2394 0.02 0.01694 2.261

Long-time Inverse(U8) CO8 5.95 2 0.18 5.95

5.1.5 EXAMPLE OF TC CURVE EDITING

3-parameters are applied in the follwing order. The values in the parenthesis are examples.

9 Time Multiplier : 1.5

9 Time Adder : 0.03

9 Minimum Response Time : 0.1

In the next figure, for example, the curve A is the basic curve. Assume the operating time of the basic curve (A) at 16 times pickup current is 0.04 sec. When applying Time Multiplier, curve ‘A’

changes its shape, that is, the curve becomes less steep in time axis and operation time becomes longer by a multiplier at the same current value like ‘B’ in the figure. The operating time at 16 times pickup becomes 0.06 sec. Then Time Adder shall be applied. The operating time of the

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resulting curve ‘C’ is 0.09sec. Finally Minimum Response Time cuts the curve part, which is shorter than this time. Then the actual operating time of the example at 16 times becomes 0.1sec.

Figure 5-1 TC Curve Editing Example 1

There are two additional definite time over-current elements in the controller. The next figure shows 3-stage over-current protection characteristics. The third stage is prepared for instantaneous protection. Therefore the harmonic restraint is not applied to third stage elements, but the second stage definite time over-current element.

Figure 5-2 TC Curve Editing Example 2

www.jinkwang.co.kr 41 / 111 5.1.6 Auto Reclosing Sequence

The FTU-R200 supports 3-shot reclosing with sequence coordination.

For Permanent fault, under the condition of reclosing enabled, no other restraints such as cold-load, inrush and no High Current Trip, recloser will be locked out to open the Reclosing Count repeating trip and reclose according to the preset settings.

Range Def. Step Unit Comment

For example in the below figure, the reclosing sequence is organized in 2F2D, which means the Recloser protection function operates as Instantaneous(Fast) element during first 2 reclosing shots and operates as Time-Delayed element during last 2 reclosing shots. This composition also can be configured.

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Figure 5-3 Permanent Fault: 3 shot Reclosing & 2F2D

For temporary fault, if the fault is removed before the preset Reclosing Count and no fault is detected during the preset Reset Time, then the reclosing sequence is initialized to normal operation standby mode. When a fault is detected again during the Reset Time, the Recloser will be locked out after the remaining reclosing counts excluding the previously operated reclosing counts.

Figure 5-4 Temporary Faults: Fault Removal during 1st Reclosing Interval

www.jinkwang.co.kr 43 / 111 5.1.7 Sequence Coodination

In case that there are over 2 Reclosers which operate in serial connections, Sequence Coordination function prevents unnecessary trip of source-side Recloser by instantaneous element due to load-side fault. When this function is set to on and the fault is restored to normal state by load-side Recloser during source-side Recloser’s time-delayed operation, source-side Recloser only increments the reclosing counts without tripping. However, source-side Recloser performs tripping at the last reclosing count. If the Reclosing function is disabled, Sequence Coordination function is no longer carried out.

Range Def. Step Unit Comment

Seq. Coordination Active OFF/ON OFF

For Sequence Coordination, the following setting items should be issued and checked precisely between serially connected Reclosers.

9 Identical Protection Characteristics such as TC Curves, Total Operation Count, Instantaneous Operation Count

9 Identical Reclosing Interval(Dead Time)

9 Source-side TC Curve Time Delay Over 100msec than Load-side

9 Source-side Reset Time longer than Load-side longest Reclosing Interval (to Prevent Source-side Recloser reset during Load-side Reclosing action)

Figure 5-5 Operation of Sequence Coordination

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5.2 Cold Load Pickup

Cold Load Pickup is the phenomenon that takes place when a distribution circuit is re-energized following an extended outage of that circuit. Cold load pickup is a composite of two conditions:

inrush and loss of load diversity. The magnitude of cold load pickup current is a combination of non-diverse cyclic load current, continuously operating load current, transformer magnetizing current, capacitor inrush current, etc. The combination can result in current levels that are significantly higher than normal peak load levels. Cold load pickup current can be high enough to cause instantaneous overcurrent and/or time overcurrent relays to operate.

Cold load pickup is primarily an overcurrent condition. If degraded voltage is also a concern, then the application of voltage sensitive relays should also be considered.

Figure 5-6 Cold Load Pickup Current Shape

In Cold Load Pickup mode, without changing operational characteristics, pickup level is changed by the times of Cold Load Multiplier (0~10) and the characteristics of time-delayed element operate even if the setting is in the Instantaneous element. If the transient current goes down and retrains below the pickup level within Cold Load Duration, then the normal sequence mode is restored after Cold Load Restore Time. The Cold Load Restore Time is fixed value of 30msec. These setting exist for both phase fault and earth fault separately, and the value ‘0’ of Cold Load Multiplier means Cold Load Pickup Function disabled. Normaly Reclosing Sequence mode is applied.

www.jinkwang.co.kr 45 / 111 5.3 SENSITIVE EARTH FAULT (SEF) DETECTION

On the grounded network, it is hard to detect fault current because ground current of non-grounded network is much low. Therefore, FTU-R200 is designed to measure zero-sequence values from either external core Balanced Current Transformer (or ZCT) or Residual Connection of 3 Phase Current Transformers to detect earth fault in the non-grounded network. This function is generally called SEF detection.

In case of earth fault in the non-grounded network, since very small fault current due to line capacitance component flows into the fault point from both sides, SEF detection also considers the fault direction even in the radial network. Maximum Torque Angle is for setting the phase difference between zero-sequence voltage and zero-sequence current, and the protection zone is between -90° and +90° on the basis of Maximum Torque Angle. And it can be used for alarm or Trip.

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5.4 DIRECTIONAL BLOCKING

Directional Blocking is a protection feature that restricts tripping on faults to a designated side of the recloser. It prevents nuisance tripping if particular network conditions are causing ‘False’

earth faults. In radial systems Directional Blocking prevents nuisance tripping by blocking faults in the reverse direction and only responding to faults in the foward direction.

Protect for faults in the forward and reverse direction. A forward fault may use a different time-current curve and setting to a reverse fault (i.e. these are individually selectable). Both the forward protection and reverse protection are operating at the same time. This is an additional protection feature.

www.jinkwang.co.kr 47 / 111 5.5 INRUSH RESTRAINTS

Inrush Restraint works by raising the phase and earth currents for a short period of time to allow the inrush current to subside.

Inrush current is an over-current higher than pickup current level, which is mainly caused by transformer’s excitation current at closing action. To distinguish inrush current from load current, 2nd harmonics percentage is adopted as a criterion.

When, in the setting, ‘Fault Detection-Inrush Block’ is set to ‘Yes’ and ‘Fault Detection-Inrush Detection-Function In Use’ is set to ‘ON’, inrush current over pickup level is considered as normal load current and reclosing sequence is not processed.

This Function can be used to detect magnetizing inrush condition by comparing 2nd harmonic component to fundamental frequency component of current.

Range Def. Step Unit Comment

2nd Harmonic 5~50 20 1 %

Detection Time 0.02~1.00 0.02 0.01 sec

Function In Use OFF/ON ON

5.6 OPEN LINE DETECTION (LOSS OF PHASE)

Open Line is detected by Under Voltage characteristics at unbalanced condition.

When the voltage on one or two phases drops below the ‘Volt OFF Level’ setting, the ‘Delay Time’ starts running. If the voltage on those phases stays below ‘Volt OFF Level’ setting until the

‘Delay Time’ timer expires, the Loss of Phase will be detected.

If the voltage on detected phase rises to the ‘Vol ON Level’ setting, the Loss of Phase is released immediately.

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5.7 PHASE SYNC. CHECK

Range Def. Step Unit Comment

Phase Difference 5~60 30 1 Degree

Dalay Time 0.1~30.0 0.1 0.1 sec

Function In Use OFF/ON ON

5.8 UNDER VOLTAGE PROTECTION

As the supplied voltage to load lowers down, there occur the weakness of illumination intensity and shortening of life span for lighting load, and the damage to motors because of the over-current flow. To cope with this situation of damages to equipment, under-voltage protection (UV) is used. UV of FTU supports the delay time element. Furthermore, UV can be used to generate only alarm signal to operator instead of trip signal to Recloser.

Figure 5-8 Functional Diagram for Under Voltage Protection

Range Def. Step Unit Comment

Pickup Level 0.30~0.95 0.80 0.01 PU

Delay Time 0.0~180.0 1.0 0.1 sec

Function In Use OFF/ARAMP/TRIP OFF

www.jinkwang.co.kr 49 / 111 5.9 OVER VOLTAGE PROTECTION

On the other hand, as the supplied voltage goes up behind the regular load voltage, there occur some problems of equipment deterioration, insulation breakdown, equipment life span shortening, etc. Over Voltage Protection (OV) manages this situation. OV of FTU supports the delay time element. OV also can be used to generate only alarm signal to operator instead of trip signal to Recloser.

Figure 5-9 Functional Diagram for Over Voltage Function

5.10 UNDER FREQUENCY PROTECTION

Under Frequency protection (UF) element is used into expenditure that detect under frequency and separated load or generator. Under Frequency demands for power increase or occurs in control failure of generator.

Under Frequency protection element acts in case of voltage more than ‘Voltage OFF Level’ is approved to Voltage A-Phase. UF of FTU supports the delay time element. Furthermore, UV can be used to generate only alarm signal to operator instead of trip signal to Recloser.

Range Def. Step Unit Comment

Pickup Level 1.05~1.50 1.20 0.01 PU

Delay Time 0.0~180.0 1.0 0.1 sec

Function In Use OFF/ARAMP/TRIP OFF

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5.11 MULTIPLE PROTECTION GROUPS

The FTU-R200 supports up to 4 Protection Groups, each of which can be confiqured with completely separate protection characteristics with different inverse time curves and setting currents. The number of protection group avaliable to the operator can be configured.

And FTU-R200 support Automatic Protection Group Selection. Automatic Protection Group Selection is used to change the protection group depending on the direction of power flow. This allows the Recloser to be correctly graded with devices downstream regardless of the power flow direction.

Range Def. Step Unit

Default Group 1~4 1 1

ADGS(Automatic Default Group Selection) Function OFF/ON OFF

Reverse Group 1~4 1 1

Range Def. Step Unit Comment

Pickup 47.00~59.98 49.80 0.01 Hz

Dalay Time 0.03~10.00 0.10 0.01 sec

Function In Use OFF/ARAMP/TRIP OFF

www.jinkwang.co.kr 51 / 111 6 CONFIGURATION SETTING

6.1 I/O CONFIGURATION 6.1.1 AC RATING

9 SWITCH INSTALLATION

The FTU-R200 provides a function to set ‘Reference Phase’ and the ‘CT Direction’ according to the switch installation position and the current flowing direction.

Figure 6-1 shows the general and ‘assumed-default’ case of switch installation, in which the distribution lines with current A, B, C are connected to the phase A, B, C terminals of the switch, and the current is flowing A/B/C to R/S/T of the switch. In this case, the ‘Referece Phase’ setting value should ‘A’, which means that the phase of current flowing into the phase A terminal of the switch is ‘A’, In addition, the ‘CT Direction’ setting value should be ‘Foward’, which means that the current is flowing in the direction from the phase A/B/C terminals to the R/S/T terminals of the switch.

Range Def. Step Unit Comment

Line Configuration Y-G/DELTA Y-G

Systme Frequency 50/60 50 40 Hz

Rated Voltage (L-L) 1000~30000 22900 10 V Phase to Phase

Reference Voltage (L-N) 1000~30000 13200 10 V Phase to Earth

Reference Phase A/B/C A

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Figure 6-1 Switch installation position and the current flowing direction – Case 1

Figure 6-2 shows another case of switch installation, in which the distriburion lines with current A, B, C are connected to the phase A, B, C terminals of the switch, and the current is flowing from R/S/T to A/B/C of the switch. In this case, the ‘Referece Phase’ setting value should ‘A’, which means that the phase of current flowing into the phase A terminal of the switch is ‘A’, In addition, the ‘CT Direction’ setting value should be ‘Reverse’, which means that the current is flowing in the direction from the phase R/S/T terminals to the A/B/C terminals of the switch.

Figure 6-2 Switch installation position and the current flowing direction – Case 2

www.jinkwang.co.kr 53 / 111 Figure 6-3 shows another case of switch installation, in which the distriburion lines with current A, B, C are connected to the phase C, B, A terminals of the switch, and the current is flowing from R/S/T to A/B/C of the switch. In this case, the ‘Referece Phase’ setting value should ‘C’, which means that the phase of current flowing into the phase A terminal of the switch is ‘C’, In addition, the ‘CT Direction’ setting value should be ‘Reverse’, which means that the current is flowing in the direction from the phase R/S/T terminals to the A/B/C terminals of the switch.

Figure 6-3 Switch installation position and the current flowing direction – Case 3

Figure 6-3 Switch installation position and the current flowing direction – Case 3