Handling the Probe 3 N2791A/N2891A High-Voltage Differential Probes 4 Contents and Accessory Kits 5 Characteristics 7 Safety Information 9 Using the N2791A High-Voltage Differential Probe 10 Using the N2891A High-Voltage Differential Probe 11 N2791A Plots 12 N2891A Plots 16 Using the Accessories 20...
Office. • If the shipping container is damaged, or the cushioning materials show signs of stress, notify the carrier as well as your Keysight Technologies Sales Office. Keep the shipping materials for the carrier’s inspection. The Keysight Technologies office will arrange for repair or replacement at Keysight Technologies’...
(up to 700 V of differential or common mode voltage for the N2791A and up to 7000 V of differential or common mode voltage for the N2891A). The N2791A offers user-...
Contents and Accessory Kits Contents and Accessory Kits The following table lists the parts included with the N2791A high-voltage differential probe. Part Quantity N2791A 25 MHz differential probe Safety Hook, Red Safety Hook, Black Alligator Clip, Red Alligator Clip, Black...
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Contents and Accessory Kits The following table lists the parts included with the N2891A high-voltage differential probe. Part Quantity N2891A 70 MHz differential probe Safety Hook, Red Safety Hook, Black High Voltage Alligator Clip, Red High Voltage Alligator Clip, Black USB Power Cord (2 m) AA Battery Trimmer Tool...
Characteristics Characteristics Characteristics for the N2791A and N2891A high-voltage differential probes are shown below. The probe / oscilloscope should be warmed up for at least 20 minutes before any testing and the environmental conditions should not exceed the probe’s specified limits.
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202 mm x 83 mm x 38 mm (8.0 inches x (6.7 inches x 2.5 inches x 0.83 inches) 3.3 inches x 1.5 inches) Environmental Specifications (same for both N2791A and N2891A) Temperature Operating: -10 °C to +40 °C Nonoperating: -30 °C to +70 °C...
Observe Maximum Working Voltage To avoid injury, do not use the N2791A probe above 1000 Vrms CAT II (both 10:1 and 100:1 attenuation settings) between each input lead and earth or between the two input leads. Do not use the N2891A probe above 5000 Vrms CAT I (1000:1 attenuation) or 500 Vrms CAT I (100:1 attenuation) between the two input leads.
Using the N2791A High-Voltage Differential Probe Use Proper Power Source To ensure this probe functions well, use four AA batteries or the supplied USB power cord. For Indoor Use Only Only use this probe indoors. Do Not Operate With Suspected Failures If you suspect there is damage to this probe, have it inspected by a qualified service personnel.
Using the N2891A High-Voltage Differential Probe Using the appropriate probe accessories, connect the inputs to the circuit under test. To protect against electrical shock, use only the accessories supplied with this probe or in the accessory kit. This probe is to carry out differential measurements between two points on the circuit under test.
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N2791A Plots Vout/Vin Vout Frequency (MH z) Graph of dB(Vin), dB(Vout) + 20dB, and dB(Vout/Vin) + 20dB frequency response, 10:1 attenuation Vout/Vin -2.5 Vout -7.5 Frequency (MH z) Graph of dB(Vin), dB(Vout) + 40dB, and dB(Vout/Vin) + 40dB frequency response,...
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N2791A Plots -100 Frequency (H z) Graph of dB(Vout/Vin) + 20dB frequency response when inputs driven in common mode (common mode rejection), 10:1 attenuation Ω 22 pF Frequency (H z) Magnitude plot of probe input impedance versus frequency (single-ended mode)
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N2791A Plots 1100 V rm s Frequency (H z) Typical derating plot of the absolute maximum input voltage in common mode...
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N2891A Plots Frequency Hz Graph of dB (S21) + 40 dB frequency response, 100:1 attenuation Frequency Hz Graph of dB (S21) + 60 dB frequency response, 1000:1 attenuation...
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N2891A Plots Frequency (Hz) Graph of dB (S21) + 40 dB frequency response when inputs driven in common mode (common mode rejection), 100:1 attenuation differential 5 pF single-ended 7.2 pF Frequency (Hz) Magnitude plot of probe input impedance versus frequency, single-ended and differential...
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N2891A Plots Vrms Frequency (Hz) Typical derating plot of the absolute maximum input voltage in common mode Input impedance equivalent circuit diagram...
Using the Accessories Using the Accessories The accessories supplied with the N2791A and N2891A probes are attached by pushing them onto the probe leads as shown below. hook or clip probe lead The following accessories are supplied with the N2791A probe and with the N2791-68700 Accessory Kit.
6 Disable the Fluke calibrator output, disconnect the channel 1 active head from channel 1 of the oscilloscope. 7 Connect the output of the N2791A probe to channel 1 of the oscilloscope. 8 Attach the BNC adapter to the Fluke channel 1 active head.
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N2791A Performance Verification Procedures 9 Attach the differential probe input leads by clipping the alligator clamp to the BNC adapter banana post. 10 Set the probe to 100:1. Set the Fluke calibrator to 10 V and 1 KHz standard amplitude output (channel 1, square wave, 1 MΩ load).
N2791A Performance Verification Test Record N2791A Performance Verification Test Record Keysight Technologies N2791A 25 MHz Differential Probe Serial No.:________________________ Certification Date:________________ Tested By:_______________________ Recommended Test Interval: 1 Year _________________________________ Recommended Date of Next Certification:_________ _________________________________ Certification Temperature:_____________________ Test Probe Settings...
BNC Adapter BNC (f) to Dual Banana (m) Keysight 1251-2277 Interconnection Adapter between probe and generator 50 Ω BNC Feed Through 50 Ω precision feed through Keysight 11048C Termination Adapter between probe and calibrator for bandwidth verification DC Differential Gain Accuracy WARNING: Generator produces hazardous voltages.
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N2891A Performance Verification Procedures 2 Set the volts/division on channel 2 of the oscilloscope to 500 mV/div. Trigger on channel 2, select 50 Ω impedance. 3 Set the calibrator 9500B’s channel 2 as the trigger channel (50 Ω load). Connect the calibrator’s channel 2 active head to channel 2 of the oscilloscope.
N2891A Performance Verification Test Record N2891A Performance Verification Test Record Keysight Technologies N2891A 70 MHz Differential Probe Serial No.:_______________________ Certification Date:________________ Tested By:_______________________ Recommended Test Interval: 1 Year _________________________________ Recommended Date of Next Certification:_________ _________________________________ Certification Temperature:_____________________ Test Probe Settings...
Follow this procedure to perform the offset zero calibration. 1 Connect the N2791A/N2891A probe to channel 1 of the scope. Turn on the probe power. You may use the USB power code or batteries to power the probe. Select the probe attenuation ratio to 10:1 (for N2791A) or 100:1 (for N2891A).
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Operation of any electrical instrument in such an environ- ment constitutes a definite safety hazard. • Do not use the instrument in a manner not specified by the manufacturer. Keysight Technologies 1900 Garden of the Gods Road Colorado Springs, CO 80901...
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