Relay Test Equipment

The HMJBC-802 Relay Test Equipment is an industrial control relay protection tester, built-in all English Windows platform operating software. Equipped with trackball mouse, optimized keyboard and large-screen TFT LCD display. can verify various relays (such as current, voltage, inverse time, power direction, impedance, differential, low cycle, synchronization, frequency, DC, intermediate, time, etc.) and microcomputer protection, and can simulate various complex transients Conduct a whole set of tests for non-permanent, permanent, and conversion failures.

1.With standard 4-phase voltage and 3-phase current output, various combined outputs can be conveniently performed for various types of protection tests. Each phase voltage can output 300V, current three can output 90A, the 4th phase voltage Ux is a multi-function voltage item, which can be set to 4 kinds of 3U0 or check synchronous voltage, or output under any voltage value.

2.The single machine is operated by a convenient and flexible optical trackball mouse through the large-screen LCD display, all in English. It can complete most of the field test and verification work, can verify various relays and microcomputer protections, and can simulate various complex transient, permanent, and transitional faults for a whole set of tests. It can be used after booting, and the operation is convenient and quick.

3.Through the full set of English operating software on the Windows platform, various large-scale, complex and more automated calibration tasks can be performed, and various protection settings can be easily tested and scanned, test data can be stored in real time, vector graphics can be displayed, and drawing Fault waveforms, online printing reports, etc.

4.The software can complete various large-scale and complex calibration tasks with a high degree of automation, such as three-phase differential test, factory power quick-cutting, automatic switching test, line protection check simultaneous reclosure, etc. It can easily test and scan various protection settings , Perform fault playback, store test data in real time, display vector diagrams, print reports online, etc.

5.Abundant contacts. Relay Test Equipment has 10 contact inputs and 8 empty contact outputs. The input contact is compatible with 0-250V potential contact and can be automatically recognized.

6. Large screen TFT display. This machine adopts 800×600 dot matrix large-screen TFT high-resolution true-color liquid crystal display, all operation processes are set on the display, the operation interface and test results are displayed in Chinese, and the display is intuitive and clear.

7. Self-protection. Relay Test Equipment adopts a reasonably designed heat dissipation structure, and has a variety of reliable and complete protection measures, soft start of the power supply, and certain fault self-diagnosis and blocking functions.

8. Relay Test Equipment is a cross-professional joint design product that integrates advanced scientific and technological achievements from multiple disciplines. It combines the performance of a large-scale tester and the price of a small-scale tester, and has a high performance-price ratio.

Switch quantity and time measurement

1. Control the digital signal processor microcomputer

This HMJBC-802 Relay Test Equipment industrical control relay test equipment uses a high-speed, high-performance digital control processor as the control microcomputer, and a double-precision algorithm is applied to the software to generate arbitrary high-precision waveforms for each phase. Due to the integrated structure, each part is tightly combined, the data transmission distance is short, and the structure is compact. It overcomes the problem of low output waveform points caused by long data communication lines and narrow frequency bands in the notebook computer directly controlled measurement and control instrument.

The output part adopts DSP control, which has fast calculation speed, strong real-time digital signal processing ability, transmission frequency bandwidth, and high-resolution D/A conversion control. The output waveform has high precision, low distortion and good linearity. Adopting a large number of advanced technology and precision components and materials, and carrying out a professional structural design, the device is small in size, light in weight, full-featured, easy to carry, and it can be started to work, and the flow test is very convenient.

High-performance embedded industrial control computer and 8.4 "large-screen high-resolution color TFT LCD display, which can provide rich and intuitive information, including the current working status of the equipment, next-step work prompts and various help information, etc.;

2. Voltage and current amplifier

The current and voltage of each phase do not use the current and booster, but the direct output mode, so that the current and voltage source can directly output the waveform from DC to the waveform containing various frequency components, such as the combination of square wave and the superposition of various harmonics Waveform, fault transient waveform, etc., can better simulate the current and voltage characteristics of various short-circuit faults.

The power amplifier circuit uses imported high-power high-fidelity modular power devices as the power output stage, combined with a carefully and reasonably designed heat dissipation structure, with sufficient power redundancy and heat capacity. The power amplifier circuit has complete overheating, overcurrent, overvoltage and short circuit protection. When there is overcurrent in the current loop and overload or short circuit in the voltage loop, the output power is automatically limited, the entire power amplifier circuit is turned off, and an alarm signal is displayed. In order to prevent the power amplifier circuit from overheating caused by long-term work under high current, the device has set a software time limit under high current. The device can work for a long time when the output is 10A and below. When the current exceeds 10A, the software will start in a limited time. When the limited time is up, the software will automatically turn off the power output and give an alarm indication. The larger the output current, the shorter the time limit.

3. Binary input and output

The switch input circuit is compatible with empty contacts and 0～250V potential contacts. In the electric potential mode, 0～6V is combined and 11～250V is divided. The switch value can conveniently measure the action time and the action time difference of each phase switch contact.

The input part is isolated from the host's working power supply and power amplifier power supply. The binary input ground is a floating ground, so the common terminals of the binary input parts are not connected to the common terminals UN and IN of the current and voltage parts.

The switch potential input has directionality. The common terminal should be connected to the positive terminal of the potential, and the open input terminal should be connected to the negative end of the potential to ensure that the potential of the common terminal is higher than the open input terminal. When wiring on site, connect the open input common terminal to +KM, and connect the negative end of the contact to the open input terminal. If the connection is reversed, it will not be detected correctly.

The open part is the relay empty contact output. The output capacity is DC: 220V/0.2A, AC: 220V/0.5A. Switch output and voltage, current, binary input and other parts are completely isolated. The action process of each output is different in each test module. For details, please refer to the software operating instructions of each module.

The connection diagram of two kinds of familiar digital output are as follows:

4. LCD display and rotating mouse operation

The device uses 800×600 high-resolution TFT liquid crystal display as the display. The whole process of the test and the test results are displayed on the display screen. A full set of Chinese character operation interface is clear and beautiful. The operation control is carried out by a photoelectric trackball mouse and two buttons. All data and test procedures are set by the mouse on the display screen. The operation is simple and convenient, and easy to master.

5. Dedicated DC power output

The device is equipped with a dedicated adjustable DC power output on the chassis bottom panel, which can be divided into 110V and 220V, which can be used as an auxiliary power supply for field tests. A potentiometer is also set up for the power supply, which can be adjusted in the range of 80%-110%. The power supply has a rated working current of 1.5A, which can be used as a DC working power supply for protection devices or as a power supply for tripping and closing circuits. If the power supply is overloaded or short-circuited, the corresponding fuse (2A/250V) will be burned out, and this fuse can be replaced at this time.

6. Install independent adjustable DC power supply

The device is equipped with an adjustable DC power output on the bottom of the chassis, which can be divided into two levels of 110V and 220V, which can be used as an auxiliary power supply for field tests. The power supply is also equipped with a potentiometer, which can be adjusted in the range of 80% -110%. The maximum output current of the power supply can reach 1.5A. A cooling fan, power cord, grounding terminal and three fuses are additionally installed on the bottom plate. One of the three insurances is the total power insurance (10A/250V), and the other is the voltage loop insurance (2A/250V).

The differential module can be tested not only by three-channel current but also by six-phase current. When three phase current is adopted, the largest output of every phase current can achieve 40A.

Most of Parameters Setting Values of protection give the current value directly. For example, the value of differential threshold is 2A, the unit is A. However, the setting values given by some protection are not current value but a coefficient. For example, the value of differential threshold is 0.3 without an unit. Actually, it is the setting value of protection given in the mode of ‘Per Unit Value’. You can convert per unit value to actual current as the following formula: Actual current value = per unit value × rated current on high voltage side.

● Calculating method of Rated current:

Ie1=Sn /（1.732﹡U1n﹡CT1）

Ie2=Sn /（1.732﹡U2n﹡CT2）

In which:

Ie1、Ie2 — transformer I、II side secondary rated current

Sn — the largest rated capacity of transformer

U1n、U2n — transformer I、II side primary rated voltage

CT1、CT2 — CT ratio respectively on the primary side and on secondary side

Note ：Some protections have calcualtion function themselves,in this case , Ie1、Ie2 are calculated without considering 1.732 mentioned in above formula. For example, calculating Ie1, directly according to the formula: Ie1= Sn /（1.732﹡U1n﹡CT1）.The reason is that the equilibrium factor includes 1.732 when calculating the differential and brake current.

Take connection of transformer Y/Y/△-11 as example, calculating mode of each side’s equilibrium factor is as follows:

K1=1/1.732=0.577

K2=U2n﹡CT2/（1.732﹡U1n﹡CT1）

K2=U3n﹡CT3/（U1n﹡CT1）

If setting equilibrium factor on high voltage side to be 1, and convert other sides to high voltage side, its calculation formula is as follows:

K1=1

K2=U2n﹡CT2/（U1n﹡CT1）

K2=1.732﹡U3n﹡CT3/（U1n﹡CT1）

Calculating equilibrium factor in terms of current is as follows:

K1=1

K2=Ie1/Ie2

K2= Ie1/Ie3

In which：

K1、K2、K3 — equilibrium factor on Transformer I、II、III side

Ie1、Ie2、Ie3 — secondary rated current on Transformer I、II、III side

U1n、U2n、U3n — primary rated voltage on Transformer I、II、III side

CT1、CT2、CT3 — CT transformation ratio on Transformer I、II、III side

Note ：

Equilibrium factor of differential protection are not all the same, the calculating mode of some protections may not be the same as the above-mentioned one. Please refer to corresponding instruction when doing the test.

1. In order to prevent the body from inducing static electricity when the tester is running. Before the test, the host must be reliably grounded through the ground terminal;

2. Pay attention to safety when outputting voltages above 36V to prevent electric shock accidents;

3. It is forbidden to add external voltage and current to the voltage and current output terminals of the tester. During the test, be sure to prevent the external voltage on the tested protective device from being fed back to the output terminal of the tester and damage the tester;

4. Pay attention to keep the air flow through the vents on the side of the chassis, please do not block the vents, so as not to affect the heat dissipation;

5. It is strictly forbidden to short-circuit the voltage test channel and open the current test channel. It is strictly forbidden to introduce external AC and DC power into the voltage source and current source output jacks of the instrument, otherwise the instrument may be damaged;

6. During the test, please do not switch the power frequently, so as not to damage the instrument or reduce the accuracy of the test;

7. During the test, if an abnormal situation is encountered, the power supply should be cut off immediately;

8. Do not place the device in the open air and get wet by rain; when the device works abnormally, please contact the manufacturer in time and do not repair it yourself.

Brief analysis and wiring method of relay protection tester's binary input principle

When testing the relay protection device, the input of the relay protection tester is closely related to whether the protection device operates or not, and the operation time. The relay protection is often tripped in the field test, but the relay tester does not receive the action contact. Check the input wiring and the protection action are all good, and it also shows normal when the binary input is short-circuited separately for testing. In response to such problems, we can start with the analysis of the principle of opening input.

Take the binary input as an example. The binary input of other circuits has the same principle as the binary input A, and shares the power supply and COM terminal. The voltage source voltage is U1 and O1 is an optocoupler. The negative side of the optocoupler is connected to the main board of the test device. When the optocoupler changes from on to off or from off, that is, when the on and off state of the optocoupler changes, the tester will record the optocoupler The moment when the state changes.

The working principle of this circuit: O1 minimum conduction current is Imin, maximum operating current is Imax, loop current is I, when I≥Imin, O1 is on, when IImax, The circuit is burned out. In the following, we will explain the two cases of no potential contact and potential contact.

1. Without potential contacts:

Wire directly from the trip terminal of the protection device without introducing a DC power circuit. There may be two connection methods during the test:

1. Take the two points 1 and 2 to connect to the binary inputs COM and A of the test device. Since there is no potential, the two points can be switched at will. At this time, if the switch is divided, the circuit is open, I=0, and the optocoupler fails. When the protection device gives a trip signal, the switch will switch from on to on. At this time, (the values of U1, R1, and R2 are fixed) the optocoupler is turned on, and the test device records the action. This kind of connection usually does not appear abnormal during testing.

2. When connecting from points 1 and 3, one more resistor R is inserted in the loop. At this time, the size of the current I depends on R. The larger R is, the smaller I is. When R is large enough to cause I

Two, with potential contacts

When the protection device has been connected to the system and the system's DC system is live, it is assumed here that the voltage between +KM and -KM is U2, and the direction is positive and negative. At this time, the COM of the test device must be connected to a positive potential. If it is connected reversely, no matter how the wiring is connected, the optocoupler is always in the on state, which has nothing to do with whether the protection is tripped or not, so it must be excluded. There may be multiple connection methods under normal wiring. The following three examples are used for analysis:

1. COM contact 1, A contact 2, the current when the switch is not closed in this case, U2 is the system voltage, 110V or 220V, U1 is the internal voltage of the test device, generally 24V, at this time, the current I＜0, the optocoupler fails . The protection trips. When the switch is closed, the voltage at both ends of the switch is 0V. At this time, the current and the optocoupler are turned on, and the test device records the action.

2. COM contact 1 and A contact 3. In this case, when the switch is not closed, the current will flow and the optocoupler will fail. When the protection trips and the switch is closed, the voltage across the switch is 0V. At this time, the current and the optocoupler are still blocked, and the test device cannot record the action, so this connection is wrong.

3. COM contact 2 and A contact 3. In this case, when the switch is not closed, the current, if R is small, can make I≥Imin, then the photocoupler is turned on, when the protection trips and the switch is closed, the voltage on the resistor R UR=U2, current and optocoupler are blocked. In this way, the optocoupler changes from on to off, the state changes, and the test device can normally record the operating time. If R is large, the current will be blocked when the switch is not closed. In this case, no matter whether the switch is closed or not, the optocoupler will not work, and the test device cannot normally record the protection action. Therefore, this connection method is the same as the second connection method without potential. The normal test depends on the size of R, and it is generally not recommended.

In addition, there are other wiring methods and pure potential testing. The principles are the same as those listed above, so I won’t repeat them.

To sum up, in the field test, whether it is a non-potential contact or a potential contact, the first wiring method listed in the two cases should be used as much as possible, and no abnormality will usually occur. When it is unable to record normally, you can throw off the protection wiring, and use the short wiring to short-circuit A and COM directly when the test device is running. If the test device can record the action normally, the fault of the relay protection tester can be eliminated.