DC resistance tester

I. Overview

The DC resistance of transformers is a necessary measurement item for semi-finished and finished products in transformer manufacturing, factory testing, installation, major repairs, changes to tap changers, handover testing, and preventive testing by power departments. It is possible to check the welding quality of the winding joints and whether there is a turn to turn short circuit in the winding. It can also detect whether the various positions of the voltage tap changer are in good contact, whether the actual position of the tap changer matches the indicated position, whether the lead wire is broken, and whether there are broken wires when multiple wires are wound together. In order to meet the needs of rapid measurement of transformer DC resistance, our company has developedofXX10ADC resistance testerThe instrument adopts a new power technology, which has the characteristics of small size, light weight, large output current, good repeatability, strong anti-interference ability, and protective function. The whole machine is controlled by a high-speed microcontroller, with a high degree of automation and automatic discharge and discharge alarm functions. The instrument has high testing accuracy, easy operation, and can achieve rapid measurement of transformer direct resistance.

two、DC resistance testerFunctional Features

1The instrument can use an Android phone or tablet, follow the WeChat official account, and downloaduseAPPControl the instrument through dedicated software, store and upload test data for easy access.

2The highest output power of the instrumentpress24VFacilitate the selection of larger test currents when high resistance values are present, thereby improving testing speed

3The instrument adopts a new power technology, with multiple current levels and a wide measurement range, which canAutomatically select current based on load, suitable for measuring DC resistance of small and medium-sized transformers and voltage transformers.

4It has multiple protection functions such as back electromotive force impact, disconnection and power outage during testing, and overheating of the power supply, which can reliably protect against the impact of back electromotive force on the instrument,And synchronize the sound alarm.

5It has the function of converting copper and aluminum materials to any temperature, allowing for touch input of any winding temperature and temperature conversion.

6Intelligent power management technology ensures that the instrument operates at its minimum power state, effectively saving energy and reducing heat generation.

7Seven inch high brightness touch color LCD, clear display under strong light, full touch screen operation, free switching between Chinese and English.

8The instrument comes with a perpetual calendar clock and power down storage, which can be storedstore1000The group test data can be accessed at any time.

9The instrument has Bluetooth communication，RS232communicationandUSBInterface, used for computer communicationandUDisk data storage.

10 Equipped with a panel type micro printer, it can print measurement results in Chinese.

3、 Main technical indicators

4、 Panel structure

AC220 openclose Instrument working power supply, ACflow220V.

pick up land pillar Grounding point and safety protection for the entire instrument

I+TheI-Output current terminal，I+Positive output current，I-Negative output current.

V+TheV- Voltage sampling terminal，V+For the positive terminal of the voltage line，V-The negative terminal of the voltage line.

RS232Universal serial interface, which can control instruments through computers.

USBcanto, toward, at, facingUOutput test results from the disk.

wind fan exhaust vent

5、 Instrument operation instructions

1The startup interface displays as shown in Figure 1:

Figure 1

2. Enter the following interface for data testing, as shown in Figure 2

Figure 2

Sample model: Pointhit Editable sample name (maximum length can be entered)enter16Chinese characters);

winding temperature: Pointhit Can bounceexitYou can set the temperature, clickDelete, clickConfirm, clickreturn;

converted temperature: Pointhit Can bounceexit You can set the temperature, clickDelete, clickConfirm, clickreturn;

tap position:pointhitcanplayexit Settings, clickDelete, clickConfirm, clickreturn;

Test phase: ClickatABTheBCTheCATheAOTheBOTheCOTheAmBmTheBmCmTheCmAmTheAMOmTheBmOmTheCmOmTheabThebcThecaTheaoTheboThecoCycle between them;

Winding Material: ClickThe winding material can be selected;

test current: ClickcurrentatAUTOThe<20mAThe40mAThe200mAThe1AThe5AThe10ACycle between them;

3After selecting the current, clickStart measurement, Showshow“Charging in progress, please wait a momentwait”Enter the testing mode, and after a few seconds, the test results will be displayed, as shown in Figure 3

picturethree

After displaying the test results, you can clickhit Directly switchtap positionThere is no need to return to the main interface. After switching to the tap position, wait patiently for a few seconds for the test results to appear. You can clickUDisk storageclickPrinting,Print test data；clicksign out,Exit the testing interface；

3 Click in Figure 1data managementEnter the data query interface, as shown in Figure 4:

Figure 4

pointhit Can query historical data, delete data, and alsocanUDisk storage and printing data, clickexitReturn to the main realmnoodles;

4Click in Figure 1System SettingsEnter the system settings interface, as shown in Figure 5:

Figure 5

Figure 6

brightness adjustmentThe screen brightness can be adjusted by moving the buttons according to the on-site environment.

Bluetooth connection:pointhit“Bluetooth connectionpick up”Pop up the QR code (as shown in Figure 6),Scan the QR code with the corresponding software downloaded from the mobile phone to achieve mobile phone functionalityControl the instrument throughout the entire process.

Language settings:Click the button to switchmiddle/English interface.

factory settingsOnly the manufacturer can set it.

Set up clicksReturn to the homepage,Return to the main interface.

4 Click in Figure 1Clock modification,Enter the clock modification interface, as shown in Figure 7:

Figure 7

click Set the date and time;

6、 Testing and operation methods

A： Single phase measurement method, as shown in Figure 8:

Figure 8

BThe auxiliary magnetic method wiring is shown in Figure 9-11 (applicable)YuY（N）-d-11Connection group).

When measuring the low voltage side of a large capacity transformer, if under existing conditions,DC resistance testerThe maximum current is relatively small, or to speed up the measurement, you can chooseMagnetic assisted measurement.In the following figure, Figures 8, 9, and 10 respectively show the measurement of lowpressRacTheRbaTheRbcThe wiring method

1 After measuring the inductive load, the test line cannot be directly removed to avoid endangering the measurement due to inductive dischargetry Safety of personnel and equipment. The output terminal of this machine is equipped with a discharge circuit. After resetting the instrument, the inductor will release energy through the instrument. The test line can only be removed after the discharge indicator is completed.

2 For no-load tap changers, it is not allowed to switch tap changers during the measurement process.

3If the power suddenly loses during the measurement process, this machine will automatically start discharging. Please do not immediately disconnect the wiring, at least waitwait 30 The wiring can only be removed after seconds.

4When measuring, other untested windings should not be short circuited to ground, otherwise it will cause the transformer magnetization process to slow down, the data stabilization time to be prolonged, or the values to be incorrect.

5Please check the power supply before turning on the devicepress:hand overflow220V±10%，50Hz.

6Please confirm that the tested equipment has been powered off and disconnected from other live devices during the experiment.

7The casing must be reliably grounded during the experiment.

8During the experiment, unrelated items are not allowed to be stacked on or around the equipment panel.

9 When replacing the fuse and accessories, please use the same model as this instrument (see technical specifications for details)

10This instrument should be moisture-proof and oil proof.

11When selecting the current, reference should be made to the measurement range in the technical specifications column. When exceeding the range, due to the current not reaching the preset value, the instrument will remain stuckat“Charging in progresselectricity”At this point, press the reset button to reset the instrument and select a smaller current gear again.

8、 After sales service

Within one year from the date of purchase, any quality issues related to the company's products will be repaired free of charge, and lifetime warranty and technical services will be provided. If any abnormalities or malfunctions are found in the instrument, please contact the company in a timely manner to arrange a convenient solution for you and provide you with the fastest on-site service.

9、 Instrument completeness

“Easy Control Softwaredocument”Install

1Follow the publicnumber“Easy Control Softwaredocument”

2Enter the official account and enter the name of the instrument that needs software: DC resistance

3. Click on the address

Method 1: Click on the download link and then go to the top right cornersquare“…”Select from the middle

“Play in browseropen”

方法二:Long press the download link address and select copy, then paste and open it in the address box of the mobile browser

4 Click to download-complete-Installation