Introduction
Brief Description
The PT-5250 Differential Probe is an instrument that provides safe isolation for all oscilloscopes. It can convert high input differential voltages (up to 50 kV peak to peak) into a low voltage (±5V), displaying the waveform on the oscilloscope. It operates at frequencies up to 60 MHz and is designed for high voltage applications. The probe's output is designed for the oscilloscope's 1 MΩ input impedance, with a relative attenuation. When using a 50 Ω terminator, the attenuation is exactly doubled. The PT-5250 Differential Probe is also recommended for observing more accurate actual test voltage values on a digital multimeter (oscilloscope accuracy is 3%, digital multimeter accuracy is approximately 10 times higher).
What's Included
- BNC Coaxial Cable (BP-250) - 100 cm
- 9V DC Adapter (ADP-220)
- High Voltage IC Clips (BP-266N) - 1 pair
- High Voltage Banana Plug Transmission Lines (BP-367) - 30kV DC / 60 cm - 1 pair
- High Voltage Alligator Clips (BP-276N) - 1kV CAT III - 1 pair
- High Voltage Extension Cable (ETL-3100) - 1 meter / 30 kV DC
- Ground Extension Cable (ETG-6100) - 1 meter / 6 kV DC
- Instruction Manual
Safety Precautions
Please read the instruction manual carefully before use:
- Be careful of electric shock!
- Pay attention to the maximum input voltage!
- Maximum differential voltage: 50 kVp-p (±25 kV DC+AC peak) or 17 kV RMS
- Differential mode voltage input for pulse or single-shot wave: 14 kVRMS
- Maximum voltage between input and ground: 25 kVp-p (±12.5 kV DC+AC peak) or 8.8 kV RMS
- Do not operate this product in a humid environment or in potentially explosive conditions!
- Do not use this product with its cover open!
- When opening the product cover, disconnect the output and input terminals!
When measuring high voltages above ±10 kV (DC+AC peak) or 5 kV RMS, the ground lead must be securely connected before measurement to prevent damage to the oscilloscope.
High Voltage Operation Precautions
- When measuring high voltages above 1 kV, do not hold the unit by hand. It is recommended to place it on a workbench for testing.
- For mains voltage measurements (including single-phase and three-phase), do not exceed 8.8 kV RMS.
- For three-phase voltage measurements, do not exceed 8.8 kV RMS. Measurement time should not exceed 30 seconds. After testing high voltage, turn off the unit and let it rest for 30 minutes to allow internal high-voltage resistors to dissipate heat.
Specifications
| Parameter | X5000 Range | X500 Range |
|---|---|---|
| Bandwidth | DC - 20 MHz (-3dB) | DC - 60 MHz (-3dB) |
| Attenuation | X5000 | X500 |
| Accuracy | ±2% | |
| Input Voltage Range (peak to peak) | ≤ 50 kV (approx. 17 kV RMS or ± 25 kV DC) | ≤ 5 kV (approx. 1.7 kV RMS or ± 2.5 kV DC) |
| Maximum Allowable Input Voltage | Max. Differential Voltage: 50 kV peak to peak Max. Voltage between input and ground: 8.8 kV RMS |
|
| Input Impedance | Between terminals: 280 MΩ // 1.5 pF Single-ended to ground: 140 MΩ // 3 pF |
|
| Output Voltage | ≤ ±5V | |
| Common-mode Voltage | 8.8 kV RMS | |
| Output Impedance | 50 Ω | |
| Rise Time | ≥ 17.5 ns | ≥ 4.7 ns |
| Noise | ≤ 1 mV RMS | |
| Noise Rejection Ratio | 60Hz: >80dB; 100Hz: >60dB; 1MHz: >50dB | |
| Power | Requires external 9V DC power supply (must use company-specified product) | |
Probe Panel Description
The PT-5250 probe is a handheld device with several controls and indicators:
- Input Terminal: Connection point for the high voltage signal.
- Output Terminal: BNC connector for outputting the signal to an oscilloscope.
- Attenuation Selection and Power Switch Knob: Used to select the attenuation factor (X500, X5000) and to turn the probe on/off.
- Overload Indicator Light: Illuminates when the input voltage exceeds the probe's range.
- Power Indicator Light: Illuminates when the probe is powered on.
- External Power Input Terminal: Connector for the 9V DC power adapter.
The probe is grey and black, with clear labeling for each function. Accessories include various test clips (IC clips, alligator clips), connection cables, and a power adapter.
Operating Environment and Conditions
| Condition | General Use | During Operation | Storage |
|---|---|---|---|
| Temperature | +20°C ~ +30°C | 0°C ~ +50°C | -30°C ~ +70°C |
| Humidity | ≤ 70% RH | 10% ~ 85% RH | 10% ~ 90% RH |
Dimensions and Weight
Dimensions: 275 x 147 x 34 mm
Weight: 488 g
Operating Procedure
- Connect the BP-367 and BP-266N (or BP-276N) accessories together, then plug them into the input terminal of the PT-5250. Make contact with the BP-266N (or BP-276N) and the object to be measured.
- Connect the BP-250 to the output terminal of the PT-5250, and then connect it to the oscilloscope.
- If necessary, first adjust the vertical controls on the oscilloscope.
- Adjust the attenuation settings and vertical controls on the oscilloscope to match the positions indicated in the table below.
Attenuation and Input Voltage Settings
| Attenuation | X5000 Range | X500 Range |
|---|---|---|
| Max. Input Voltage (Peak to Peak) | 50 kV p-p | 5 kV p-p |
| Max. DC Input | ± 25 kV | ± 2.5 kV |
| Max. AC RMS Input | 17 kV RMS | 1.7 kV RMS |
Oscilloscope Vertical Deflection Conversion
The actual vertical deflection is calculated by multiplying the oscilloscope's selected vertical deflection by the attenuation factor. If a 50 Ω load is used, the actual voltage value is doubled.
| Oscilloscope Vertical Deflection (V/DIV) | Actual Deflection (V/DIV) - X5000 Range | Actual Deflection (V/DIV) - X500 Range |
|---|---|---|
| 1 | 5 kV | 500 V |
| 0.5 | 2.5 kV | 250 V |
| 0.2 | 1 kV | 100 V |
| 0.1 | 500 V | 50 V |
| 50 m | 250 V | 25 V |
| 20 m | 100 V | 10 V |
| 10 m | 50 V | 5 V |
| 5 m | 25 V | 2.5 V |
| 2 m | 10 V | 1 V |
Example: If the probe is set to x 500 and the oscilloscope's vertical deflection is set to 1 V/div, the actual vertical deflection is 500 x 1 V/div = 500 V/div. If the oscilloscope input is loaded with 50 Ω, the deflection becomes 500 V/div x 2 = 1 kV/div.
Maintenance, Cleaning, and Warranty
Maintenance
When maintaining this product, please use tools specified by the manufacturer. The manufacturer will not be responsible for repairs performed by unauthorized personnel.
Cleaning
This product does not require any specific cleaning. If necessary, use a soft, clean cloth lightly dampened with a small amount of cleaning solution to wipe the exterior of the product.
Warranty
Except for intentional damage caused by human factors, this product is covered by warranty and can be repaired. It does not include responsibilities related to safety regulations. The warranty covers replacement of parts and shipping costs, up to the amount of the invoice.
The warranty covers damage caused only under normal operating conditions and does not include intentional damage, operational errors, improper mechanical operation, improper maintenance, overload, or overvoltage.
The manufacturer's warranty is limited to the replacement of damaged parts. Users cannot claim direct or indirect liability from the manufacturer. The manufacturer's warranty is valid for 12 months from the date of sale. If any unauthorized repair or part replacement is performed, the manufacturer's warranty will be voided.
Repair
For any repairs, maintenance, or part replacements outside of the warranty period, please return the product to the manufacturer for repair.
High Frequency Withstand Voltage Curve
The graph below illustrates the relationship between maximum input voltage and frequency under common-mode conditions. It shows a general trend where the maximum allowable voltage decreases as frequency increases.
Key data points:
- 1 kHz / 50 kVp-p
- 100 kHz / 40 kVp-p
- 500 kHz / 30 kVp-p
- 1 MHz / 25 kVp-p
- 3 MHz /15 kVp-p
- 20 MHz / 7 kVp-p
- 60 MHz / 3 kVp-p
The graph axes are Frequency (Hz) on the X-axis and Voltage (V) on the Y-axis.
Packing List
| Name | Quantity |
|---|---|
| Differential Probe Main Unit | 1 unit |
| BNC Coaxial Cable (BP-250) | 1 cable |
| Banana Plug Silicone Wire (BP-366A) | 1 pair |
| IC Clip (BP-266N) | 1 pair |
| Alligator Clip (BP-276N) | 1 pair |
| 9V Adapter (ADP-220) | 1 unit |
| High Voltage Test Extension Cable | 1 cable |
| Ground Wire | 1 cable |
| Instruction Manual | 1 copy |
| Certificate of Conformity | 1 copy |
