Transformer Tester
Darui Electric recommends:
The Transformer Comprehensive Tester is based on the successfully developed transformer calibrator, using indirect method for detailed analysis of transformer mathematicalTransformer Tester；However, test results depend on the accuracy of the equivalent model and measurement precision of each parameter. The instrument can measure CT volt-ampere characteristics and curves (1A, 5A), 5% and 10% error curves, DC resistance, ratio polarity, CT dynamic stability and short-time thermal current tests per national standards. It can directly measure PT ratio, measure bushing CTs installed in transformers, qualitatively measure PT ratio error and polarity, and perform on-site measurement of actual secondary burden of CTs and PTs. The instrument uses high-precision, auto-linear-regulated DC and AC power supplies, high-speed high-reliability digital processing modules, high-power output to meet test requirements while being portable for field use, and high-precision high-stability front-end measurement circuits ensuring measurement accuracy and stability. It can operate in harsh environments including high temperature, high humidity, marine, desert, extreme cold, and high altitude conditions.
Product Features
The product features:
Automatic mode: uses indirect method - fast, simple, and convenient.Auto-adapts 380V AC and 220V AC power, automatically calculates knee point voltage/current and composite error, intuitively determines transformer qualification. Fully automatic VA characteristic curve testing and plotting eliminates manual voltage adjustment, recording, organizing and curve drawing. No special training required, easy to master. Suitable for schools, laboratories and other well-controlled environments.Disadvantages: longer test cycles, lower reliability; larger size, requires external power supply; requires several minutes of preheating before use in low-temperature environments.
Manual mode: uses direct method that truly reflects actual test conditions (accurate and reliable results); VA characteristic and other high-power tests can run continuously (short test cycle) with good reliability.Compact and simple structure, low cost, no external power required. Modular design enables multi-unit combination. Suitable for harsh field environments with high temperature, heavy dust and extreme cold.Disadvantage: low level of automation.
Comprehensive Functions: Can test protective CT VA characteristics, 5% and 10% error curves, DC resistance, ratio, and polarity.
1) The instrument can perform qualitative PT measurements: by applying a power frequency voltage to the primary side of the PT, it measures primary voltage and secondary induced voltage to determine the PT ratio and polarity at that voltage, and can perform VA characteristic tests on PTs.
2) The instrument can measure on-site secondary burden of CTs and PTs, and measure CT ratio error and phase error under that burden.
Large-screen graphic LCD, full Chinese graphic interface：clear, elegant, intuitive and convenient.Directly displays VA characteristic curves during testing. Built-in thermal printer for quick printing of curves and test data; supports data storage at any time.
High Expandability:
a) External voltage regulator testing: if the standalone output voltage or current is insufficient, a user-supplied 20kVA-30kVA voltage regulator can be connected for testing. External voltage regulator (weight 86kg-105kg) test wiring and method are very simple; appropriate protection circuits required for circuit and personnel safety.
b) Optional external booster: selected external booster up to 2000V/3A, can be used for VA characteristic testing of 5000/1 class current transformers.
Storage and Printing, all parameter settings are retained after power loss.
Technical Specifications
3.1VA Characteristic Technical Specifications:
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Input Voltage
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Output Range
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Measurement Range
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Measurement Accuracy
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Main Unit
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AC220V
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0～550V, 0～20A
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0～550V, 0～20A
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< =0.5%
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Main Unit
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AC380V
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0～950V, 0～20A
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0～950V, 0～20A
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< =0.5%
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External Booster
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AC220V
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0～2000V，0～3A
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0～2000V，0～3A
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< =0.5%
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External Voltage Regulator
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A220V |
0-250V，0-80A |
0～1000V，0～30A
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< =0.5%
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Power Supply
Power
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AC 220V±10%，50/60Hz
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Operating Environment
Temperature
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-10℃ - +50℃
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External Measurement
Power Supply (long-term
continuous operation)
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AC 220V or AC 380V
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Dimensions, Weight
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240×320×350mm3，28kg
(No external power supply or 380V power required)
420×300×270mm3， 34.5Kg
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3.2CT Measurement Range:
Ratio: 5A/5A~25000A/5A (5A/1A~5000A/1A).
Turns ratio error: 1%.
3.3PT Measurement Range:
2.2kV~132kV, measurement error: ratio error class 0.5.
3.4Actual Secondary Burden Test
PT burden 10VA~500VA, measurement error: class 2
CT burden 0.1Ω~25Ω, measurement error: class 2
3.5-inchOperating Conditions:
Supply Voltage: AC 220V ±10%
Supply Frequency: 50Hz ±2%
Ambient Temperature: (-10~40)C
Ambient Humidity: <85% at 25C
Altitude: below 5000m
3.6 Precautions:
1. CT secondary winding must not have grounding points.
2. For bushing CTs installed in transformers, restore original wiring after testing.
3. Connect and disconnect wiring only when voltage regulator switch and output switch are in the off position.
4. The device must be reliably grounded before testing.
5. Return to zero promptly after testing. Prohibited from prolonged operation at high voltage or high current.
6. When using external booster, current booster or 380V power supply, equip with proper protection systems to ensure personnel and equipment safety.
7. If LCD screen is blank or printer malfunctions, do not strike the panel, shake the unit, or disassemble for repair; contact the manufacturer for maintenance.
8. The standalone unit is heavy; exercise caution for personal safety when moving for testing.
9、
Test personnel must maintain appropriate safety distance from the equipment under test.
Note: The above information and technical parameters are compiled and published by Yangzhou Darui Electric Co., Ltd.
