Chapter 1 Device features and technical parameters
Section 1 Main features(LY808 Relay Protection Analyzer)
¿Flexible combination of voltage and current output
Six phase voltage and six phase current can be output, which has made it is possiable to be any combition, such as the output mode of the combination of conventional four phase current and three-phase current, six phase voltage mode, six phase current mode and 12 phase output mode. It not only can be compatible with the traditional way of various tests, but also can conveniently carry out differential test of three-phase transformer.
¿Operation mode
The device is directly connected with a computer or a desktop computer, which is convenient and efficient and stable performance.
¿A new hi-fi linear power amplifier
The output port has always insisted on using the modular linear power amplifier instead of the switching power amplifier, which has the high fidelity and high reliability function and excellent performance. High-mid frequency will not be produced to disturb the test, also ensure the smoothing accuracy of waveform produced by the whole course of the high current to the tiny current is excellent.
¿High performance Mainframe
The output part adopts DSP control, which has fast operation, real-time digital signal processing capability, wide bandwidth and high resolution D/A conversion control. The output waveform has the features of high precision, small distortion and good linearity. With using a large number of advanced technology and precision components and materials and the structure of professional design, the device has the features of small volume, light weight, full function, easy to carry, boot can work, flow test is very convenient.
¿Powerful software function
It can complete all kinds of high automatic validation work which is large and complex. It can also conveniently test and scan protection setting, playback of fault, real-time store test data, display vector, online print report and so on. Besides, six-phase current can facilitate the test of three-phase differential protection.
¿IndependentDCpower output
An 110V and 220V adjustable DC power is designed to supply output.
¿Complete interface
The device with USB communication port can communicate with the computer and other external devices.
¿Perfect self-protection function
With reasonable design of the heat dissipation structure and the reliable and perfect hardware protection measures, it has the power soft start function and the software of the fault self-diagnosis and the output latch function.
Section 2 Nominal parameter(LY808 Relay Protection Analyzer)
¿ Parameter
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Type
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Current channel number
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Standard six phase
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Voltage channel number
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Standard six phase
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AC current output range
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30A / phase or 180A (six phase parallel)
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DC current output range
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10A DC /phase
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AC voltage output range
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120V AC /phase
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DC voltage output range
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160V DC / phase
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¿ Nominal parameter
AC current output
The virtual value of each phase output when six phase current output 0~30A output precision 0.1 grade
The virtual value of each phase output when three phase current output 0~60A
The virtual value of six phase parallel current output 0~180A
The allowed virtual value when the phase current work long time 10A
The maximum output power of phase current 450VA
The maximum output power when six phase parallel current output 1000VA
The allowed working time when six phase parallel current maximum output 10s
Frequency range(fundamental wave) 0~1000Hz
Harmonic order 0~20
DC current output
Current output 0~±10A / phase output precision 0.2 grade
The maximum load volatage output 20V
AC voltage output
The virtual value of phase voltage output 0~120V output precision 0.1 grade
The virtual value of line voltage output 0~240V
The output power of phase voltage/ line voltage 80VA / 100VA
Frequency range(fundamental wave) 0~1000Hz
Harmonic order 0~20
DC voltage output
The output amplitude of phase voltage 0~±160V output precision 0.2 grade
The output amplitude of line voltage 0~±320V
The output power of phase voltage/ line voltage 70VA / 140VA
Input and output
8 channels input
Free contact 1~20mA,24V
Electric potential contacts “0”:0 ~ +6V; “1”:+11 V ~ +250 V
4 channels output DC:220 V/0.2 A;AC:220 V/0.5 A
Time measurment range
0.1ms ~ 9999s , measurement accuracy <0.1ms
Chapter 2 Hardware Structure(LY808 Relay Protection Analyzer)
Section 1 Hardware Structure
¿ Digital Signal Processor Microcomputer
High-speed digital controlling processor is adopted as the output core of the tester. 32 bit double precision arithmetic is employed in the software, through which arbitrary high-accuracy waveforms of each phase can be produced. Since integrative structure is adopted, the structure of the tester is layed compactly.The distance of data transmission is short with tight structure, which overcome the problem of fewer points of waveform output due to long data communicational line and narrow frequency band when using the test controller controlled directly by PC.
¿ D/A Conversion and Low-Pass Filtering
High precision D/A converter is employed for ensuring the precision and linearity of current and voltage in the whole range.
Due to high density of fitting ponit, fidelity of waveform is high and harmonic component is small, which don’t have a strict requirement on the low-pass filter. Consequently, it has good characteristics of transient, phase frequency and amplitude frequency, which is easy to perform accurate phase-shifting and harmonic superposition and ensures very high precision even when the frequency is high.
¿ Voltage and Current Amplifier
For phase current and voltage, we persist in adopting high performance linear amplifier output mode in order to make the current and voltage source to directly output all kinds of waveforms from the DC waveform to the waveforms including all kinds of frequency components, such as square wave, combined waveform overlapped by each order harmonic, fault transient waveform, etc. In addition, the output waveform is clear and smooth without high-frequency radiated interference with neighboring equipments. It can simulate well all kinds of current and voltage characteristics under the circumstance of short circuit fault.
For power amplifier circuit, we adopt import power parts with high-power and hi-fi module style as power output, combining with heat dissipation structure layed elaborately and reasonably, it has enough large power redundancy and thermal capacity. The power amplifier circuit has overheat, overflow, overvoltage and short circuit protections. When overflow occurs in the current circuit and overload or short circuit occurs in the voltage circuit, it will limit the output power automatically, switch off the whole power amplifier circuit and give alarm signal.In order to prevent the overheat of the power amplifier for long time operating under large current, a software time terminating system under large current is set in this tester. It can work for a long period when outputting is 10A or below. When the current is over 10A, the tester will start up the software time termination order. When time is up, the software will forbid power output automatically and give alarm signal. The higher output current is, the shorter the limiting time will be.
¿ Input and output
This tester has 8 channels input and 4 channels output.
The switching input circuit is compatible for both the empty contacts and 0-250V electric potential contacts in the input and output circuit. When the electric potential contacts are selected, 0-6V belongs to closed switch and 11-250V belongs to open switch. The switching capacity can test the action time and the action time interval of every phase switch’s contact conveniently.
The part of the digital input is isolated from the resources of the mainframe and the amplifier. The end of the digital input is hung, so the common end of the digital input is separated from the Common End UN, IN of current and voltage parts.
Switching potential input has directivity, you should connect the common end with the positive terminal of potential, and connecting the input end with negative terminal of potential for ensuring the potential of common end is higher than the one of input end. In practice, you should connect the input common end with +KM, and connecting the negative terminal of contact with input end.
The output part is the idle contact output of relay. Output capacity is DC:220V/0.2A,AC:220V/0.5A. Output of switching capacity is independent of voltage, current, input and all other parts. Action process of each digital output part is different in each testing module. For details, please refer to the operation instruction on software module.
The connection diagram of two kinds of familiar digital output is as follows:
Mode of potential contact
Mode of free contact
¿ Auxiliary DC Power Supply Output for Special Use
A circuit of special adjustable DC power supply output is allocated on the rear panel, which has 110V and 220V two shifts that can be used as test standby power supply on the spot. We still set a potentiometer for this power supply, it can be adjusted within the range of 80%-110%. Rated current of this power supply is 1.5A, which can be used as DC power supply of protective tester or switch loop supply. If overload or short circuit occurs, corresponding protector tube will be burned out (2A/250V), you will only need to change this protector tube at that time.
Chapter 3 Please Read the Following Instruction before Operation(LY808 Relay Protection Analyzer)
Section 1 General Rules for Use
Please do not shut off power supply directly during outputting so as to avoid the wrong protection action due to incorrect output.
When switch quantity is compatible with both idle contact and the potential (0~DC250V) and uses charged contact, the high terminal (anode) of contact potential should be connected with the common end +KM.
When taking the tester into operation, make sure that the air slots, the power switch and the power supply plug at the test set remain unobstructed.The instrument should be laid uprightly, or unfold the bracket for slightly tilted placement
Do not lead external AC/DC power into the voltage and current output sockets of tester.
If the disturbance is stronger on the spot or high safety is required, before doing the test, please ground the outlet of power source or the protective earth of the tester.
If the interface data is wrong or you can not input correctly when using this tester, you can settle the problem as follows: delete the ‘para’ file under the ‘E\Relaytestar\, and then restart the running program, all data on the interface will be resumed to the default.
Section 2 Procedures of turning on/off Tester
¿ Procedures for Turning On
Plug the power line of tester in AC220V outlet. If using external computer, please connect well the serial communication line with computer’s serial interface and the communication interface on the bottom of the tester.
Method one: Start up the Windows operating system firstly, and then enter the main software interface of ‘Relaytestar’.
Method two: It wills automatic recover the Windows operating system, which will need four minutes. Then enter the interface which can choose the way of starting up.This way is mainly used when the Windows operating system is damaged and cannot nomal start, which can make the Windows operating system restore to factory settings. The user cannot worry that the previous test report and data will be losing after self-recovery. But this way will take much time and it is not the best choice to often use.
Method three: This way will enter DOS state and mainly used by the management personnel. If the user enters DOS state carelessly, please turn off the power and wait a moment to boot again.
You can use the up and downs key or ‘1’,’2’,’3’ number key to choose the boot way within five seconds,otherwise the system will automatic start up by method one. The software interface will be showed after the Windows operating system started up. On the main interface, click all kinds of functions testing module logo by using the left key of external connected mouse or tracking ball mouse for doing all tests.
¿ Procedures for Turning Off
Please do not close down the power switch on the faceplate directly. You should terminate the Windows operating system firstly, and then press the power supply button when indication for safe turning off appears on the screen.
Move cursor on the main interface through mouse or press the ‘QUIT’ key on the faceplate to quit all functional testing units. After backing to the main interface, press the ‘QUIT’ key again, a dialog window for confirmation will be ejected on the screen. After your confirmation, you can turn off the power supply switch on the front panel when ‘You can turn off the power supply now’ appears on the screen, so the machine can be closed safely.
You can also turn off the device by choosing the ‘start’ menu of the operation system.
Chapter 4 Brief Instruction on Software Operating Method(LY808 Relay Protection Analyzer)
The Relaytestar software is new generational testing software developed byWuhanhuman Company. Its characteristics are more friendly and beautiful interface, more complete and powerful functions, and it also preserves its unique characteristic of simple and concise interface, easy operation and easy to learn. According to different functions of each testing module, we separate the testing modules to five groups, general testing, common protection, circuit protection, components protection and comprehensive function. Each group includes some sub-menus, such as the ‘common testing’ includes ‘AC Test’, ‘DC Test’, ‘Harmonic Superposition’, ‘State Series I’ and ‘State Series II’, and it can be extended at will. On the right of this window, it displays rolling introduction about the company.
Section 1 Introduction on Common Functions in Menu Bar
Name or symbols of menu items in every testing module are the same, and its definition and function are almost identiacal. We take the ‘AC Test module as example for introduction, which can be applied for all functional modules.
Opening file:The shortcut key is Ctrl+O, which is used for calling out testing parameters saved in appointed file and showing the parameters on software interface. If clicking this function, the testing parameters of current module will be saved as the following default path :E:\ Relaytestar\Para\name of current module\.
● Saving parameters:The shortcut key is Ctrl+S, which is used for saving the testing parameters on software interface and call out them again by using ‘Opening parameter’ later. Data will be saved in the default file of the current module.

Reporting Test:Shortcut key is Ctrl+R, which is used for calling out the test report saved in appointed file. The contents of test report will be displayed in the test report window and revising or printing the test report can be completed in this window. After every test, a dialog box will be ejected by the system to save the test report. The report will be saved as the following defaulted path: E:\ Relaytestar\Test Report\name of current module\
● Exit:Shortcut key is Ctrl+X,which is used for exiting current testing module。
● Start Test:It has identical function as the run key,which is used for starting the test.
● Stop Test:It has identical function as the ESC key, which is used for ending the test normally or compelled terminating program running.
● Short Circuit Calculation:After clicking it, a ‘short circuit calculation’ dialog box will be opened, which is used for short circuit calculation and automatically fill the interface with the calculated results when fault occurs just like the right chart shows. Note that zero sequence compensating factors must be set correctly when the fault type is grounding fault.
Section 2 Introduction on Common Button in the Tool Bar




Attention:
During the operation, if interface data is wrong or you can not input correctly, you can settle these problems as follows: delete the file of ‘para’ under 'E: \ Relaytestar \ in Windows system, and then restart the operating program, all data on the interface will be recovered to the default.
Chapter 5 AC Test
The ‘AC Test’module is a universal and comprehensive testing module. It has an independent testing unit with 4-phase voltage and 3-phase current output, also independent testing units with six phase voltage and six phase current output and an testing unit according to sequence component output, which can be switched between each other through 3P, 6U, 6I, 12P and five buttons of sequence component. Making use of these modules, we can carry out AC testing under all conditions in power system (note: 6 phase voltage, 6 phase current, 12 phase voltage-current function are only intended for Model 1000/1200 ). Their common features are as following: through setting corresponding voltage or current as variables, giving the variable certain changeable step size and selecting suitable testing mode (‘manual operation’, ‘semi-automation’ and ‘full-automation’ three modes are available) to test action value, return value, action time and return time of all kinds of voltage and current protection conveniently, and calculating return factor automatically. Since the ‘four phase voltage and three-phase current’ unit is used often and the operating method of other units is basically the same as it, so we only take the ‘four phase voltage and three-phase current’ as the example to introduce in detail.
Flexibly controlling output four phase voltage, three-phase current six phase voltage, six phase current, outputing full twelve phase at the same time.
Having the function of outputting according to phrase sequence component.Through setting the value of phrase sequence component directly, the module combines each phase voltage and current output automatically.
For each phrase voltage and current output, both amplitude and phase can be set arbitrarily. The amplitude can be set the upper limit.
Every component’s amplitude value, phase and frequency are variable, and the variable step size can all be set at will.
Ux can be set to be many kinds of output modes combination and also can be set arbitrary value
Full-automation, self-automation and manually operating are available,which can be switched between each other in the process of output.
Amplitude, phase, step size and numbers of variable can be revised directly in the status of output.
Power value can be displayed directly for verifying power measurer.
Action value, return value, action time and return time can be measured.
Section 1 Interface Instruction
¢ Set AC Component
After entering the effective value of voltage and current, click the ‘confirmation (enter)’ key or move the cursor to other place, the data entered will automatically be saved to three places of decimals. The default unit of voltage is V, and the default unit of current is A. When setting the phase, you can enter any angle in the range of -180~360°. If the angle overflows the above range, the system will switch it automatically into this range. For example, if entering ‘-181°’, it will be altered to be '179°’ automatically. In the vector diagram window, you can observe the real-time diagram of each AC vector.
The single phase largest output of AC voltage is 120V. If you need to output higher voltage, you can connect any two-phase voltage in series. Their amplitudes may not be the same, but the phases should be reversed .For example: set Ua to output 120V, 0°, and set Ub to output 120V ,180°, then the effective output value of Uab will be 240V.
The single phase largest output of AC current can reach 40A (when six phase current of Model 1000 output at one time, the largest output current of each phase can achieve 20A, and that of Model 1200 can achieve 30A). If larger current output is required, you can adopt parallel connection and the phase of each phase should be the same when operating in parallel. When selecting heavy current output, thicker and shorter lead wire is prefered, in addition, make sure that output time is as shorter as possible.
The ‘variable’ column alongside of the effective value set for AC component is used for choosing whether the output component is alterable. If you click the ‘variable’ column at the back of certain phase’s effective value or phase for ‘√’, it means that the output phase is alterable. Meanwhile, the ‘Step Size’ column will be changed from gray to highlight, which indicates the ‘Step Size’ setting permissible. The smallest value of variable step size of amplitude is 0.001, and the smallest value of variable step size of angle is 0.1.
The column of ‘upper limit’ is used for setting the largest output effective value of each phase. When doing the test,once the output of certain phase can’t be estimated and will result in damage to the relay, you can set an ‘upper limit value’ for this phase,therefore ,the output of this phase will be controlled within the limit value, which ensure the safe operation of relay.
¢ Ux
Ux is a special phase, it can set many kinds of output situations:
When setting it to be +3UO、-3UO、+
combining UA and UB with UC output currently to obtain 3UO component ,and then multiply their coefficient respectively to obtain the UX output value.The value always varies along with the change of UA, UB and UC.
If Ux is set to equal the value of certain phase such as UA, the output of Ux is the same as the one of corresponding phase.
If selecting the ‘Any Mode’, the output of Ux is the same as other three-phase voltage in the range of output and also can vary its amplitude and angle according to certain step size.
Attention:
There are 6 phases voltage output in the Relaytestar-1000/1200 tester, but there is not an independent special phase Ux . Consequently, the program assigned the fourth phase voltage Ua as the special phase Ux.
¢ Parameters Display
The line voltage, zero sequence, positive sequence and negative sequence components will be shown on the left side of the interface. Through this window, you can monitor the variable situation of ‘sequence component’ and ‘line voltage’. The values of this part are calculated completely according to each phase’s component value given above and can’t be obtained by setup. Through this window, the operator can observe each sequence component and values of line voltage when protection is performed, which is convenient for recording the operation data of protection according to different demands. For example, when doing low-voltage latching overcurrent test, if the line voltage is given for protection setting value, you can not only see the value of phase voltage when protection acts visually, but also can read directly the value of phase voltage from this window without calculating by operator themselves.
¢ Power Measurer Display Button

When clicking this button, a ‘Power Display’ box will be ejected just as the right figure shows.
In this displaying box, all kinds of amplitude, phase, power and other data of secondary side will be displayed default. If the data of primary side needs to be displayed, for example, when verifying on-the-spot meter, you only need to select the ‘primary side power and current’ and input corresponding TV and TA ratio. Click the ‘Power unit is megastage’ for conversion the power unit from ‘KW、Kvar’ to ‘MW、Mvar’ automatically.
¢ ‘Contact Action’ and ‘Action and Return’
When selecting the ‘Contact Action’ in the column of testaim, the tester will stop the test automatically when it receives signal of protective action, and will record the data of relay action at that time.
When selecting the ‘Action and Return’ in the column of test aim, the tester can test the data of relay action and return, and it can also calculate the return coefficient automatically.
¢ Modes of Manual Operation, Semi-automatic and Full-automatic Operation
Mode of Manual Operation
All variables are controlled by hand. Press the
key or
key on the tool bar, or press the “↓” key or“↑”key on the keyboard on front panel, each variable will increase or decrease one step. When relay acts, the tester will give a sound of ‘Di” and record the action value and time. If needing to test the return value of the relay, decreasing or increasing the variable till the relay’s contact return, the sound of ‘Di’ will disappear. The tester will record all necessary return data and calculate the return coefficient automatically.
Mode of Semi-automatic Operation
In this mode, all variable will increase or decrease automatically after starting the test when selecting ‘Increase’ or ‘Decrease’. You can set the interval of increase or decrease. When the relay acts, the tester will record action value of selected variables automatically and maintain output but the variety will be stopped temporarily. Meanwhile, a dialog box will be ejected for asking the change direction of next step, will you ‘increase’, ‘reduce’ or directly ‘stop’ the test? You should select an order according to the requirement of test.
Mode of Full-automatic Operation
In this mode, all variables will increase or decrease according to step size after starting the test when you select ‘Increase’ or ‘Decrease’. You can set the interval of increase and decrease when protection acts; it will record necessary data automatically. If the ‘only contact operation’ has been selected, the tester will stop the test after obtaining the action data automatically; if the ‘test action value and return value’ has been selected, the tester will automatically change direction after obtaining the action value and alter the value in the opposite direction till the contact of tester returns so as to measure the return value, record it and calculate the return coefficient.
Attention:
1. In the mode of ‘manual Operation’, the speeds of increase and decrease variable can not be very quickly when it almost achieve the value of protective operation, so as to ensure the variable stays for enough times at every step size for producing the action. Only doing like this, the result measured will be more accurate.
2. During the automatic test, the internal calculator will be reset to zero with each step process. When measuring the action time of relay, please select the mode of ‘manual Operation’ and make it to vary slowly if longer time is needed.
¢ Directly Set Parameter to Alter Output Value in the Output State
During the test, the software permits to use many functions to directly change output in the state of output:
You can switch the mode of ‘Manual Operation’, ‘Self-automation’ and ‘Full-automation’ in the output state, switch between ‘Increase’ or ‘Decrease’, or switch between ‘Contact Action’ or ‘Action and Return’. You can change the ‘Time interval of automatic variety’ in the mode of manual operation.
Whenever parameters need to be amended, it can be changed among all kinds of modes. Click corresponding ‘Alteration’ box to tick ‘√’ or cancel to complete this operation.
In the mode of ‘Manual Operation’, you can change output of each phase at one time. The concrete operating procedure is as following: directly input the amplitude and phase of each phase needing to be amended one by one (please do not press the ‘confirmation’ key before completing it). After finishing inputting all values, please press the ‘Confirmation’ key. Then, the tester will synchronously change output of each phase to be the corresponding input value .
¢ Input
All input of ‘Relaytestar’ Series Tester share one common terminal. When connecting the protective action contact, connect one end with the common terminal of tester and connect another end with any one of input A、B、C、R、a、b、c. Please note that if the connector has the positive potential,do connect this connector with common terminal.
In this testing module, input A、B、C、R、a、b、c are effective in default state. The relationship between them is ‘or’. When certain digital input is not needed, you can select to close it. When doing the test, switch-off and switch-on contacts of relay can be connected with any digital input (during the line protection, the software defaults the digital input R to be the signal incoming end of reclosing. When connecting the input common terminal (red terminal) with active contact, we normally connect it with the positive end of power supply. The tester will record the time in the column of input as soon as the tester receives the trigger signal of the digital input.
If the trigger signal occurs in multichannels digital input ,the corresponding data wii be recorded.
¢ Confirme the Switch State Change Time
Off/on of contacts of all kinds of relay and microcomputer protection normally has certain oscillation. To prevent the oscillation from influencing the test result, we usually set certain ‘Confirme the Switch State Change Time’. For common relay, ‘Confirme the Switch State Change Time’ is set to be 20ms,as for the microcomputer type protection, ‘Confirme the Switch State Change Time’ only needs to be set to be 5ms.
Record Test Result

There is an area for recording the ‘action value’, ‘return value’ and ‘return coefficient’ of test result on the lower right of the interface. It can record three-phase voltage, current, line voltage, voltage, positive sequence, negative sequence and zero sequence component of current, phase and frequency of AC, etc. You only need to tick the box before any item. Just as the right diagram shows
Short Circuit Calculation Button

‘AC Test’ module is a popular module. When more complex test needs to be simulated, please click the Short Calculation button in the tool column. A dialog box of ‘Short Calculation’ will be ejected, in which you can set arbitrarily.
Type of Fault
Four types of fault are available in the pulldown menu: single phase earthing short circuit, two phase short circuit, three-phase short circuit or normal state, among which the normal state means that the three phase voltage is positive sequence rated voltage and three-phase current is 0A.
Fault Direction
It is ‘Forward Direction Fault’ in the default mode. When reverse fault needs to be simulated for some directivity protection, you can select the ‘Reverse Fault’ in pulldown menu.
Rated Voltage
It represents the rated phase voltage of the system. The rated voltage usually is 57.735V.,which refers to the Non-fault phase voltage.
Setting Impedance
According to different setting valued given by the setting value list, you can set fault impedance according to ‘Z / Ф’ or ‘R / X’ two kinds of modes on the interface. Selecting which kind of mode to set setting impedance depends on the setting value list. Whatever you choose,the value of another kind of mode will be obtained through automatic calculation of the computer..
Multiple of Short Circuit Impedance
Above we set the ‘Setting Impedance’ in the setting value list, but we often verify it in 0.95 times or 1.05 times when doing the test. So ‘Short Circuit Impedance” = ‘Times Value’ ×’Setting Impedance’,involving ‘Short Circuit Impedance’ with short circuit calculation again. When doing the ‘Zero Sequence Protection’ test, the preemptive action of distance protection can be standed aside through flexible setting of short circuit impedance and in the case of not exiting the distance protection.
Model for Calculation
When selecting the ‘Maintaining Short Circuit Current’, certain short circuit current needs to be set. You can calculate the ‘Short Circuit Voltage’ of corresponding fault type by using the ‘Short Circuit Impedance’ and this ‘Short Circuit Current’ given. When selecting ‘Maintaining Short Circuit Voltage’, certain short circuit voltage needs to be set. You can calculate the ‘Short Circuit Current’ of corresponding fault type by using the ‘Short Circuit Impedance’ and this ‘Short Circuit Voltage’. When doing the ‘Distance Protection’ Test, flexible setting the short circuit impedance may avoid the priority-action of the ‘Distance Protection’ under the condition of not exiting the zero sequence protection.
Attention:
‘Short Circuit Voltage’ represents the fault line voltage when two phases is short circuit, while it refers to the fault phase voltage in the event of other types of short circuits.
Zero Sequence Compensating Factor
When simulating the ‘Earthing Distance Protection’ Test, the corresponding zero sequence compensating factor must be considered. Software gives three setting modes, please set according to the setting mode of zero sequence compensating factor given in the setting value list.
After finishing the above testing parameters setting, please click the ‘confirmation’ button, then the software will calculate the short circuit voltage, current and corresponding angles and fill these data on the ‘AC Test’ interface at once.
¢ Function of outputting according to sequence component

The following diagram shows the testing interface of sequence component:
Set directly all kinds of sequence component of voltage-current needed to be output on the interface. For example, when needing to output three phase negative sequence voltage,fill the blank after ‘U-’ with this value and software can calculate automatically the amplitude and phase relations of output voltage of each phase.
Attention:
1. You should note that the amplitude, variation step size and phase are all sequence components,which are combined by three-phase voltage or three-phase current but not actual output of single phase of tester. If changing any sequence component value on the interface (including amplitude and phase) ,software will real-time calculate corresponding three-phase voltage and current ,which will be displayed in the listing area on the lower left side of interface. The tester output voltage and current displayed on the interface rather than sequence component.
2. U0、I0、U-、I- on the interface are value of each sequence component,equaling to one third value of 3U0、3I0、3U-、3I- in general use, which is the same as the value displayed in the result list on the lower left corner of three-phase AC Test interface. When doing the test, firstly identify which one is the setting values given by protection, U0、I0、U-、I- or 3U0、3I0、3U-、3I-. If being U0、I0、U-、I-, you can set parameter directly according to the setting value; if being 3U0、3I0、U-、I-, the actual setting value should divide by 3,and then set parameters according to new setting value.