Keysight N2791A, N2891A User Manual

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N2791A 25 MHz and N2891A 70 MHz High-Voltage Differential Probes

User’s Guide

Page 2

Contents

Inspecting the Probe 3 Cleaning the Probe 3 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 N2791A Performance Verification Procedures 21 N2791A Performance Verification Test Record 23 N2891A Performance Verification Procedures 24 N2891A Performance Verification Test Record 26

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Inspecting the Probe

❏ Inspect the shipping container for damage.

Keep the damaged shipping container or cushioning material until the contents of the shipment have been checked for completeness and the probe has been checked mechanically and electrically.

❏ Check the accessories.

• If the contents are incomplete or damaged, notify your Keysight Technologies Sales Office.

❏ Inspect the instrument.

• If there is mechanical damage or defect, or if the probe does not operate properly or pass calibration tests, notify your Keysight Technologies Sales 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’ option without waiting for claim settlement.

Cleaning the Probe

Disconnect the probe and clean it with a soft cloth. Make sure the probe is completely dry before reconnecting it to an oscilloscope. Avoid using abrasive cleaners and chemicals containing benzene or similar solvents.

Handling the Probe

Handle the probe with care and refer to the safety notices at the back of this manual and on page 9. Note that the probe cable is a sensitive part of the probe and, therefore, you should be careful not to damage it through excessive bending or pulling. You should also avoid any mechanical shocks to this product in order to guarantee accurate performance and protection.

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N2791A/N2891A High-Voltage Differential Probes

The N2791A/N2891A high-voltage differential probes allow conventional earthgrounded oscilloscopes to be used for floating signal measurements (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 userselectable attenuation settings of 10:1 and 100:1 while the N2891A offers attenuation settings of 100:1 and 1000:1, making both probes highly versatile and usable for a broad range of applications including power supply measurements and motor controls. Both probes are compatible with any oscilloscope with a 1 MW BNC input. The probes can be powered by any USB port on an oscilloscope or computer, or by internal batteries (4x AA included with the probe).

The images below show some key parts of the N2891A probe body. The N2791A has similar switches/LEDs, but they are arranged differently.

on/off switch

overrange indicator

attenuation switch

Battery Use

• Insert 4 AA batteries in the back of the unit as indicated within the chassis

(see pages 10-11 for information on accessing the battery location)

• When battery life has expired, remove the batteries

• When the batteries gets close to running out, the power indicator will start

to flicker and dim

• Note the WEEE label on the batteries and dispose of properly

power LED indicator

USB power cord input

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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 1 Safety Hook, Red 1 Safety Hook, Black 1 Alligator Clip, Red 1 Alligator Clip, Black 1 USB Power Cord (2 m) 1 AA Battery 4 Trimmer Tool 1 User’s Guide 1

For N2791A replacement accessories, you can order the N2791-68700 Differential Probe Accessory Kit. It includes:

Part Quantity

Safety Hook, Red 1 Safety Hook, Black 1 Alligator Clip, Red 1 Alligator Clip, Black 1 USB Power Cord (2 m) 1

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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 1 Safety Hook, Red 1 Safety Hook, Black 1 High Voltage Alligator Clip, Red 1 High Voltage Alligator Clip, Black 1 USB Power Cord (2 m) 1 AA Battery 4 Trimmer Tool 1 User’s Guide 1

For N2891A replacement accessories, you can order the N2891-68700 Differential Probe Accessory Kit. It includes:

Part Quantity

Safety Hook, Red 1 Safety Hook, Black 1 High Voltage Alligator Clip, Red 1 High Voltage Alligator Clip, Black 1 USB Power Cord (2 m) 1

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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.

Electrical Characteristics

Characteristics

N2791A N2891A

Bandwidth (-3 dB) >25 MHz (driving 1 MW oscilloscope

input)

70 MHz (driving 1 MW oscilloscope

input) Attenuation ratio 10:1, 100:1 (switchable) 100:1, 1000:1 (switchable) Probe Risetime (10%-90%) 14 ns 5 ns Absolute Maximum Rated

1000 Vrms CAT II 5000 Vrms CAT I Input Voltage (each side to ground)

Maximum Differential Input Voltage (DC + AC Peak)

Maximum Common Mode Input Voltage

Input Impedance 4 MW, 10 pF (each side to ground)

\70 V at 10:1 attenuation

\700 V at 100:1 attenuation

\70 V at 10:1 attenuation

\700 V at 100:1 attenuation

8 MW, 8 pF (between inputs)

\700 V at 100:1 attenuation \7000 V at 1000:1 attenuation

\7000 V at 10:1 attenuation \7000 V at 1000:1 attenuation

50 MW, 7 pF (each side to ground) 100 MW, 5 pF (between inputs)

Output Voltage Swing \7 V (driving 1 MW oscilloscope input) \7 V (driving 1 MW oscilloscope

input) Offset (typical) \7.5 mV (adjustable) \5 mV (adjustable) CMRR (typical) -80 dB at 60 Hz, -40 dB at 1 MHz -80 dB at 50 Hz, -60 dB at 20 kHz Power Requirements 4 AA batteries or USB power adapter

(5 V/200 mA, 9 V/120 mA)

4 AA batteries or USB power adapter

(5 V/200 mA, 9 V/120 mA) Battery Life 15 hours (alkaline battery) 11.5 hours (alkaline battery) Battery/Power Cord The supplied voltage must be less than

12 V and greater than 4.4 V or else the probe could be damaged

- all are typical

The supplied voltage must be less

than 12 V and greater than 4.4 V or

else the probe could be damaged

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Characteristics

Mechanical Characteristics

N2791A N2891A Weight (probe only) 400 g (probe and PVC jacket) 500 g BNC Cable Length 95 cm (37 inches) 90 cm (35 inches) Length of Input Leads 45 cm (18 inches) 60 cm (24inches) Dimensions (L x W x H) 170 mm x 63 mm x 21 mm

(6.7 inches x 2.5 inches x 0.83 inches)

202 mm x 83 mm x 38 mm (8.0 inches x

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

Altitude Operating: 3,000 m

Nonoperating: 15,300 m

Humidity Operating: 25 - 85% room humidity

Nonoperating: 25 - 85% room humidity

Pollution Degree Pollution Degree 2

Safety Specifications

CEI/IEC 61010-031 CAT II (N2791A) CEI/IEC 61010-031 CAT I (N2891A)

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Safety Information

Warning To avoid personal injury and to prevent fire or damage to this product or products

connected to it, review and comply with the following safety precautions. Be aware that if you use this probe assembly in a manner not specified, the protection this product provides may be impaired.

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. Do not use the N2891A probe above 5000 Vrms CAT I (both 100:1 and 1000:1 attenuation settings) between each input lead and earth.

Must be Grounded

Before making connections to the input leads of this probe, ensure that the output BNC connector is attached to the BNC channel input of the oscilloscope and the oscilloscope is properly grounded.

Use Fused Test Prods if Necessary

If this probe is intended to be used with circuits of installation category II, it should incorporate the fused test prods.

Do Not Operate Without Covers

To avoid electrical shock or fire hazard, do not operate this probe with the covers removed.

Do Not Operate in Wet / Damp Conditions

To avoid electrical shock, do not operate this probe in wet or damp conditions.

Do Not Operate in an Explosive Atmosphere

To avoid injury or fire hazard, do not operate this probe in an explosive atmosphere.

Avoid Exposed Circuit

To avoid injury, remove jewelry such as rings, watches, and other metallic objects. Do not touch exposed connections and components when power is present.

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Using the N2791A High-Voltage Differential Probe

To replace batteries, first slip off the cover

Then slide the battery cover off on the rear of the 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 N2791A High-Voltage Differential Probe

• To use this probe, first insert the four AA batteries into the probe or connect the USB power cord to the probe and a USB port (see page 4 to see where the USB power cord input is located on the probe).

• Then connect the BNC output connector to the channel input of the oscilloscope. The oscilloscope must have a ground referenced.

• Select the proper attenuation ratio (10:1 or 100:1) on the probe via the attenuation switch and specify the attenuation and probe configuration on your oscilloscope.

TIP: When measuring signals below 70 V, switch the attenuation ratio to 10:1 in order to obtain a higher resolution signal with less noise. Otherwise set the attenuation ratio to 100:1.

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Using the N2891A High-Voltage Differential Probe

Slide the battery cover off the rear of the probe body

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. This probe is not for electrically insulating the circuit under test and the measuring instrument.

Using the N2891A High-Voltage Differential Probe

• Then connect the BNC output connector to the channel input of the oscilloscope. The oscilloscope must have a ground referenced.

• Select the proper attenuation ratio (100:1 or 1000:1) on the probe via the attenuation switch (see the picture on page 4) and specify the attenuation and probe configuration on your oscilloscope.

TIP: When measuring signals below 700 V, switch the attenuation ratio to 100:1 in order to obtain a higher resolution signal with less noise. Otherwise set the attenuation ratio to 1000:1.

• 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. This probe is not for electrically insulating the circuit under test and the measuring instrument.

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N2791A Plots

-100 -50 0 50 100 150

-0.2

0.2

0.4

0.6

0.8

1.2

Time (ns)

Volts

Step Input Signal

Measured Step Response (17 ns 10-90% rise time)

-100 0 100 200 300 400 500

-0.2

0.2

0.4

0.6

0.8

1.2

Time (ns)

Volts

Step Input Signal

Measured Step Response (17 ns 10-90% rise time)

N2791A Plots

Graph of normalized step response (50Ω, 16.5 ns rising edge step generator), 17 ns normalized rising edge (10-90%), 10:1 attenuation

Graph of normalized step response (50Ω, 17 ns rising edge step generator), 17 ns normalized rising edge (10-90%), 100:1 attenuation

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N2791A Plots

-20

-15

-10

-5

Fre q uency (MHz )

Vout

Vin

Vout/Vin

-10

-7.5

-5

-2.5

2.5

F re quency (MHz)

Vout/Vin

Vout

Vin

Graph of dB(Vin), dB(Vout) + 20dB, and dB(Vout/Vin) + 20dB frequency response, 10:1 attenuation

Graph of dB(Vin), dB(Vout) + 40dB, and dB(Vout/Vin) + 40dB frequency response, 100:1 attenuation

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N2791A Plots

-100

-80

-60

-40

-20

F re quency (H z)

Frequency (Hz )

22 pF

Graph of dB(Vout/Vin) + 20dB frequency response when inputs driven in common mode (common mode rejection), 10:1 attenuation

Magnitude plot of probe input impedance versus frequency (single-ended mode)

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N2791A Plots

100

300

500

700

900

1100

Freque ncy (H z)

Vrms

Typical derating plot of the absolute maximum input voltage in common mode

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N2891A Plots

-20 0 20 40 60 80 100

-0.2

0.2

0.4

0.6

0.8

1.2

Time (nS)

Normaliz ed S tep Response (V)

Step Input Signal

Probe Step Response (10 ns 10-90% rise time)

-20 0 20 40 60 80 100

-0.2

0.2

0.4

0.6

0.8

1.2

Time ( nS )

Normaliz ed S t ep Res pons e (V )

Step Input Signal

Probe Step Response (10 ns 10-90% rise time)

N2891A Plots

Graph of normalized step response (50 W, 10 ns rising edge step generator), 10 ns normalized rising edge (10-90%), 100:1 attenuation

Graph of normalized step response (50 W, 10 ns rising edge step generator), 10 ns normalized rising edge (10-90%), 1000:1 attenuation

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N2891A Plots

-35

-30

-25

-20

-15

-10

-5

Frequency Hz

Normalized S21+40dB

-16

-14

-12

-10

-8

-6

-4

-2

Frequenc y Hz

Normali zed S21+60dB

Graph of dB (S21) + 40 dB frequency response, 100:1 attenuation

Graph of dB (S21) + 60 dB frequency response, 1000:1 attenuation

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N2891A Plots

-90

-80

-70

-60

-50

-40

-30

-20

-10

Frequenc y (Hz)

CMRR dB

Frequency (Hz)

Input i m pedance (Ohms )

5 pF

7.2 pF

differential

single-ended

Graph of dB (S21) + 40 dB frequency response when inputs driven in common mode (common mode rejection), 100:1 attenuation

Magnitude plot of probe input impedance versus frequency, single-ended and differential

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N2891A Plots

Frequ ency (H z)

Vrms

Typical derating plot of the absolute maximum input voltage in common mode

Input impedance equivalent circuit diagram

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Using the Accessories

hook or clip

probe lead

Using the Accessories

The accessories supplied with the N2791A and N2891A probes are attached by pushing them onto the probe leads as shown below.

The following accessories are supplied with the N2791A probe and with the N2791-68700 Accessory Kit.

Safety Hook and Alligator Clips

Use the safety hooks to clamp onto smaller components and use the alligator clips to clamp onto thicker gauge devices

safety hook

The following accessories are supplied with the N2891A probe and with the N2891-68700 Accessory Kit.

Safety Hook and High-Voltage Alligator Clips

Use the safety hooks to clamp onto smaller components and use the alligator clips to clamp onto thicker gauge devices

safety hook

high-voltage alligator clip

alligator clip

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N2791A Performance Verification Procedures

The following procedure can be used to test the DC differential gain accuracy and bandwidth of the N2791A differential probe. Please note that these procedures do not indicate that these characteristics are warranted. Instead, these procedures are meant to give you an idea of how your probe performs.

Required Test Equipment

Description Critical Specifications

Digitizing Oscilloscope Bandwidth: >50 MHz

1 MΩ/50Ω selectable input

Signal Generator Precision DC voltage source

BNC Adapter BNC (f) to Dual Banana (m)

50 Ω BNC Feed Through Adapter

DC Differential Gain Accuracy

1 Set the volts/division on channel 1 of the oscilloscope to 20 mV/div. Set the

seconds/div to 200 μs and the acquisition mode to average 64.

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.

4 Connect the active head channel 1 from the Fluke 9500B to channel 1 of the

oscilloscope. Set the calibrator channel 1 to 0.1V peak-to-peak amplitude and 1 KHz (square wave, 1 MΩ load), enable the output.

5 Select the amplitude measurement on the oscilloscope and record the DC

amplitude (approximately 100 mV) of the square wave. This measurement is only the oscilloscope.

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.

Amplitude accuracy: less than or equal to 0.25%

1 MΩ/50Ω selectable load Sine wave greater than or equal to 25 MHz

Adapter 50 Ω precision feed through Keysight 11048C Termination between

Recommended Model

Part Number

Keysight MSO9254A Display probe output

Fluke 9500B Signal source for DC gain

and bandwidth

Keysight 1251-2277 Interconnection between

probe and generator

probe and calibrator for bandwidth verification

Functions

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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).

11 Enable the output of the calibrator. 12 Record the DC amplitude of the square wave and divide 100 into just the

amplitude of the oscilloscope. Verify that the probe gain accuracy is +/-2% +

scope gain accuracy.

13 Set the calibrator to 1 V output and set the attenuation button on the probe to

10:1.

14 Record the DC amplitude of the square wave and divide 10 into just the amplitude

of the oscilloscope. Verify that the probe gain accuracy is +/-2% + scope gain

accuracy.

15 Disable the calibrator output and leave the setup connected for the next

procedure.

Bandwidth

1 Connect the 50 Ω BNC feed through adapter to the calibrator’s active head

channel 1. 2 Attach the BNC (f)-to-banana post adapter to the BNC feed through adapter. 3 Attach the differential probe input leads by clipping the alligator clamp to the

BNC adapter banana post. 4 Set the probe to 10:1 attenuation. 5 Set the volts/division on channel 1 of the oscilloscope to 50 mV/div and seconds/

division to 50 ns/div. Set the trace to the center of the oscilloscope. Input

impedance should be set to 1 ΜΩ. Set the average mode to 16 points. 6 Set the calibrator to sine wave, 3 V peak-to-peak amplitude. Set the frequency

to 25 MHz, 50 Ω load. 7 Write down the peak-to-peak amplitude measured by the oscilloscope. It should

be greater than or equal to 210 mV - scope vertical accuracy. 8 Disable the generator output and disconnect the probe input.

Page 23

N2791A Performance Verification Test Record

Keysight Technologies

Recommended Test Interval: 1 Year Recommended Date of Next Certification:_________ Certification Temperature:_____________________

Test Probe Settings Limits Results

Gain 100:1 98 mV to 102 mV Gain 10:1 98 mV to 102 mV Bandwidth 10:1 Greater than or equal to 210 mV - scope

vertical accuracy

N2791A 25 MHz Differential Probe Serial No.:________________________ Certification Date:________________ Tested By:_______________________ _________________________________ _________________________________

Page 24

N2891A Performance Verification Procedures

The following procedure can be used to test and verify the DC differential gain

accuracy and bandwidth of the N2891A high voltage differential probe. Please

note that these procedures do not indicate that these characteristics are

warranted. Instead, these procedures are meant to give you an idea of how your

probe performs.

Required Test Equipment

Description Critical Specifications

Digitizing Oscilloscope Bandwidth: >50 MHz

1 MΩ/50Ω selectable input

Signal Generator Precision DC voltage source

BNC Adapter BNC (f) to Dual Banana (m)

50 Ω BNC Feed Through Adapter

DC Differential Gain Accuracy

Amplitude accuracy: less than or equal to 0.25%

1 MΩ/50Ω selectable load Sine wave greater than or equal to 25 MHz

Adapter

50 Ω precision feed through Keysight 11048C Termination

Recommended Model

Part Number

Keysight MSO9254A Display probe output

Fluke 9500B Signal source for DC

Keysight 1251-2277 Interconnection

Functions

gain and bandwidth

between probe and generator

between probe and calibrator for bandwidth verification

WARNING: Generator produces hazardous voltages. To avoid shock, do not touch exposed

metal parts after generator output is enabled.

WARNING: These procedures require the application of high voltage to the inputs of the

N2891A probe. Because this adapter has exposed metal surfaces, only qualified personnel

should perform any testing with voltage levels exceeding 30 Vrms. All pertinent safety

rules and guidelines for elevated voltage measurements should be followed and adhered

to.

1 Set the volts/division on channel 1 of the oscilloscope to 20 mV/div. Set the

seconds/div to 200 μs and the acquisition mode to average 32.

Page 25

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. 4 Connect the active head channel 1 from the Fluke 9500B to channel 1 of the

oscilloscope. Set the calibrator channel 1 to 0.1V peak-to-peak amplitude and

1 KHz (square wave, 1 MΩ load), enable the output. 5 Select the amplitude measurement on the oscilloscope and record the DC

amplitude (approximately 100 mV) of the square wave. This measurement is only

the oscilloscope. 6 Disable the Fluke calibrator output, disconnect the channel 1 active head from

channel 1 of the oscilloscope. 7 Connect the output of the N2891A probe to channel 1 of the oscilloscope. 8 Attach the BNC adapter to the Fluke channel 1 active head. 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).

11 Enable the output of the calibrator. 12 Record the DC amplitude of the square wave and divide 100 into just the

amplitude of the oscilloscope. Verify that the probe gain accuracy is +/-2% +

scope gain accuracy.

13 Set the calibrator to 100 V output and set the attenuation button on the probe

to 1000:1.

14 Record the DC amplitude of the square wave and divide 10 into just the amplitude

of the oscilloscope. Verify that the probe gain accuracy is +/-2% + scope gain

accuracy.

15 Disable the calibrator output and leave the setup connected for the next

procedure.

Bandwidth

1 Connect the 50 Ω BNC feed through adapter to the calibrator’s active head

channel 1. 2 Attach the BNC (f)-to-banana post adapter to the BNC feed through adapter. 3 Attach the differential probe input leads by clipping the alligator clamp to the

BNC adapter banana post. 4 Set the probe to 100:1 attenuation. 5 Set the volts/division on channel 1 of the oscilloscope to 10 mV/div and seconds/

division to 20 ns/div. Set the trace to the center of the oscilloscope. Input

impedance should be set to 1 ΜΩ. Disable average mode. 6 Set the calibrator to sine wave, 5 V peak-to-peak amplitude. Set the frequency

to 70 MHz, 50 Ω load. 7 Write down the peak-to-peak amplitude measured by the oscilloscope. It should

be greater than or equal to 35 mV - scope vertical accuracy. 8 Disable the generator output and disconnect the probe input.

Page 26

N2891A Performance Verification Test Record

Keysight Technologies

Recommended Test Interval: 1 Year Recommended Date of Next Certification:_________ Certification Temperature:_____________________

Test Probe Settings Limits Results

Gain 100:1 98 mV to 102 mV Gain 1000:1 98 mV to 102 mV Bandwidth 100:1 Greater than or equal to 35 mV - scope

vertical accuracy

N2891A 70 MHz Differential Probe Serial No.:_______________________ Certification Date:________________ Tested By:_______________________ _________________________________ _________________________________

Page 27

Offset Zero Calibration Procedure

The N2791A/N2891A differential probe can be adjusted for zeroing out the

probe’s offset voltage using the trimmer tool supplied with the probe. 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). 2 Short the + and - probe inputs together with the hook tips. 3 Turn on power to the oscilloscope and the probe, and leave them on for > 30

minutes so they can stabilize. 4Press [Default Setup] and [Auto Scale] on the oscilloscope. 5 Press the channel 1 button, then press the Probe softkey, and then set the units

to Volt and the probe attenuation to 10:1 (for N2791A) or 100:1 (for N2891A). 6 Set the scope to DC coupled mode and the scope offset to 0 Volt. 7 Set the oscilloscope to Averaging mode (x8 or higher) or high-resolution mode

to reduce oscilloscope noise. 8 Using the trimmer tool that comes with the probe, adjust the probe offset voltage

to 0 volts.

Page 28

Offset Zero Calibration Procedure

Page 29

Safety

Notices

This apparatus has been designed and tested in accor dance with IEC Publication 61010, Safety Requirements for Measuring Apparatus, and has been supplied in a safe condition. This is a Safety Class I instrument (provided with ter minal for protective earthing). Before applying power, verify that the correct safety precau tions are taken (see the following warnings). In addition, note the external markings on the instrument that are described under "Safety Symbols."

Warnings

• Whenever it is likely that the ground protection is impaired, you must make the instrument inoperative and secure it against any unintended opera tion.

• Service instructions are for trained service personnel. To avoid dangerous electric shock, do not perform any service unless qualified to do so. Do not attempt internal service or adjustment unless another per son, capable of rendering first aid and resuscitation, is pres ent.

• Do not install substitute parts or perform any unauthorized modification to the instrument.

• Capacitors inside the instrument may retain a charge even if the instrument is discon nected from its source of supply.

• Do not operate the instrument in the presence of flammable gasses or fumes. 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.

Safety Symbols

Instruction manual symbol: the product is marked with this symbol when it is necessary for you to refer to the instruction manual in order to protect against damage to the product or personal injury.

Hazardous voltage symbol.

Keysight Technologies 1900 Garden of the Gods Road Colorado Springs, CO 80901

Page 30

Notices

No part of this manual may be reproduced in any form or by any means (including electronic stor age and retrieval or translation into a foreign language) without prior agreement and written con sent from Keysight Technologies, Inc. as governed by United States and international copyright laws.

Manual Part Number N2791-97003, Aug 2014

Print History N2791-97002, Feb 2011

N2791-97001, Nov 2009 N2791-97000, May 2009 Keysight Technologies, Inc.

1900 Garden of the Gods Road Colorado Springs, CO 80907 USA

Restricted Rights Legend If software is for use in the per-

formance of a U.S. Government prime contract or subcontract, Software is delivered and licensed as “Commercial com puter software” as defined in DFAR 252.227-7014 (June

1995), or as a “commercial item” as defined in FAR 2.101(a) or as “Restricted computer software” as defined in FAR 52.227-19 (June 1987) or any equivalent agency regulation or contract clause. Use, duplication or disclo sure of Software is subject to Keysight Technologies’ standard commercial license terms, and non-DOD Departments and Agen cies of the U.S. Government will receive no greater than Restricted Rights as defined in FAR 52.227-19(c)(1-2) (June

1987). U.S. Government users will receive no greater than Lim ited Rights as defined in FAR

52.227-14 (June 1987) or DFAR

252.227-7015 (b)(2) (November

1995), as applicable in any tech nical data.

ity and fitness for a particular purpose. Keysight shall not be liable for errors or for incidental or consequential damages in connection with the furnishing, use, or perfor mance of this document or of

any information contained herein. Should Keysight and the user have a separate

written agreement with war ranty terms covering the material in this document that conflict with these terms, the warranty terms in the separate agreement shall control.

Technology Licenses The hardware and/or software

described in this document are furnished under a license and may be used or copied only in accordance with the terms of such license.

WARNING

A WARNING notice denotes a hazard. It calls attention to an operating

procedure, practice, or the like that, if not correctly performed or adhered to, could result in

personal injury or death. Do not proceed beyond a WARNING notice until the indicated conditions are fully understood and met.

CAUTION

A CAUTION notice denotes a hazard. It calls attention to an operating procedure, practice, or the like that, if not correctly performed or adhered to, could result in damage to the product or loss of important data. Do not proceed beyond a CAUTION notice until the indicated conditions are fully understood and met.

Document Warranty

The material contained in this document is provided “as is,” and is subject to being changed, without notice, in future editions. Further, to the maximum extent permit

ted by applicable law, Keysight disclaims all warranties, either express or implied, with regard to this manual and any information contained herein, including but not limited to the implied warranties of merchantabil

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Keysight Technologies, Printed in the Philippines August 2014 Manual Part Number: N2791-97003

*N2791-97003*