The PFRS-25 is a power transformer frequency sweep response analyzer designed to confirm the mechanical integrity of a power transformer by measuring the frequency response per the IEEE C57.149-2012 and IEC 60076-18 standards. The included test and analysis software can be used to perform tests automatically and to graphically compare test results and provide correlation analysis per the IEEE C57.149-2012 and DL/T 911-2004 standards. The software can be used to quickly assess the mechanical and electrical integrity of the transformer under test.
The PFRS-25 can confirm the mechanical integrity of a transformer by comparing the frequency response of the transformer with the previous known results. Every transformer has a unique frequency response system which changes if the mechanical geometry of the transformer is changed. These changes can occur due to physical movement or transportation. The physical geometry can also change if the transformer experiences high fault current due to internal or external fault. The fingerprint comparison of the frequency response system can be used to detect power transformer problems such as:
- Core movements
- Shorted turns or open windings
- Winding displacements or deformations
- Winding connection problems
- Broken clamping structures
The PFRS-25’s sweep range is user selectable from 0.1 Hz – 25 MHz. A typical test sweep time, with frequency ranging from 20 Hz to 2 MHz, is less than 25 seconds. A quick sweep test can be performed in under 10 seconds to confirm proper cable connections.
The PFRS-25’s test voltage range is programmable from 0.2 Vpp to 20 Vpp in 0.2 Vpp steps. This enables the user to match the test voltage to tests performed by another manufacturer’s device.
The PFRS-25 offers a dynamic range greater than 130 db with a measurement accuracy of ±0.5 db. THe higher dynamic range eliminates the effects of noise and facilitates the comparison of different sweeps.
The PFRS-25 is computer-controlled via USB or wirelessley via Bluetooth. The Bluetooth feature allows test personnel to be at a comfortable distance from the transformer for increased safety and productivity.
An optional built-in battery backup is also available that can provide power for up to three hours. The PFRS-25 uses a sealed lead acid battery (12V, 7AH).
Windows-based sweep frequency response analysis software is included with each PFRS-25. The software can perform tests automatically and can be used to analyze the test data. The test data can be compared with previous data to analyze any changes. The software graphically compares test results as a magnitude vs. frequency plot, phase vs. frequency graph, or display both graphs at the same time. The software provides an analytical tool that can perform correlation coefficients between two traces per the IEEE C57.149-2012 or DL/T 911-2004 standard.
Users can quickly run tests in the field using pre-defined test connections. These include user-defined configurations as well as configurations defined by the IEEE C57.149-2012 standard. Test data can be exported to XML and EXCEL formats. The PFRS-25 software can import SFRA test records allowing the user to compare the PFRS-25 test records against other devices on the market.
- Technical Specifications
- Downloads
ENVIRONMENT |
|
| Ambient Temperature | |
| Operating | -20°C to +55°C (-4°F to +131°F) |
| Storage | -20°C to 70°C (-4°F to +158°F) |
| Humidity | < 95% RH, non-condensing |
CE MARKING |
|
| EMC | 2004/108/EC |
| LVD | 2006/95/EC |
GENERAL |
|
| AC power supply | 90 – 264 V AC, 47 – 63 Hz |
| Internal battery | 3.2 Ah, 38 Watts |
| Dimensions | 13" x 11" x 6" (34 cm x 29 cm x 15 cm) |
| Weight | 10.0 lbs. (4.5 Kg) Includes the field rugged ABS Enclosure |
| Transportation Case (optional) | 24.5” x 19.37” x 12.22” / 62.33 cm x 49.2 cm x 31.04 cm |
MEASUREMENT SECTION |
|
| Frequency Range | 0.1 Hz – 25 MHz, user selectable |
| Frequency Resolution | 0.01% OR 0.001Hz |
| Frequency Accuracy | 0.01% (measurement error) |
| Level Resolution | 0.0005 dB |
| Number of Points | Default 1046, Up to 32,000 points (user selectable) |
| Measurement Time | <20 S, fast setting 6 s (20 Hz – 2 MHz) |
| Points Spacing | Log, linear, or both |
| Sweep Settings | 20 Hz to 2 MHz |
| Internal Noise Level (average) | >140 dB |
| Dynamic Range | >150 dB |
| Accuracy | ±0.1 dB from +10 to -40 dB and ±0.3 dB (min) below -40 dB |
| IF Bandwidth | User selectable; default <10% |
| PC Communication | USB and Bluetooth |
| Software | Windows-compatible |
| Standards/Guides | Fulfills requirements in IEC 60076-18, IEEE C57.149-2012, CIGRE Technical Brochure 342, DL/T 911-2004, as well as other international standards and recommendations |
ANALOG OUTPUT |
|
| Channels | 1 |
| Compliance Voltage | 0.2 – 24 V p-p |
| Measurement voltage at 50 Ω | 0.1 – 12 V P-P |
| Channel Protection | Short-circuit and over-voltage protection |
| Sweep Direction | Low to high or high to low |
| Frequency Range | 0.1 Hz – 25 MHz, user selectable |
ANALOG INPUT |
|
| Channels | 2 |
| Sampling | Simultaneous |
| Frequency Range | 0.1 Hz – 25 MHz |
| Input Impedance | 50 Ω |
| Sampling Rate | 100 MS/s |
