Agilent Technologies N2771A User manual

User’s Guide
Agilent Technologies N2771A 15 kV High Voltage
Probe
WARNING This high voltage probe is designed to prevent accidental shock to the operator when properly
used. This operating note must be read and understood prior to using the probe. Improper
procedures or incorrect analysis of the measurement situation can result in serious shock.
General Information
The Agilent Technologies N2771A High Voltage Divider Probe is an accessory to be used with analog
or digital oscilloscopes having input resistance of 1 MΩ(±1%) and nominal input capacitance between
6 and 20 pF. The Agilent Technologies N2771A is a 1000:1 divider which extends the voltage
measurement capability to 15 kV dc or 10 kV rms ac (30 kV peak).
Characteristics (Not Warranted)
Maximum Input Voltage Temperature Coefficient
DC Voltage: 15 kV
AC Voltage: 10 kV RMS
PEAK Voltage: 30 kV
Less than 200 ppm/ °C
Compensation Range Division Ratio
For input capacitance of 6 pF to 20 pF 1000:1
Bandwidth Pollution Degree 2
50 MHz (-3 dB)
Input Resistance Operating Temperature
1 GΩ, when terminated by 1 MΩ0°C to +50 °C
Cable Length: Storage Temperature:
2 meter −20 °C to +70 °C
Altitude: Humidity
Up to 4,600 meters (15,000 ft) Up to 80% relative humidity at +40 °C
s1

2
Voltage Derating
The following graph shows the voltage versus frequency derating curve for the Agilent N2771A High
Voltage Probe.
Voltage Versus Frequency Derating Curve
Frequency Compensation Adjustment
The N2771A High Voltage Probe has a Frequency Compensation adjustment that compensates for
the input capacitance of the oscilloscope being used with the probe.
Use a square-wave generator set for approximately 100 Hz output. Proceed with the following steps
for frequency compensation.
1Connect the probe to the oscilloscope.
2Connect probe tip to square-wave generator.
3Adjust the square wave generator for approximately 10 volts amplitude.
4Adjust the oscilloscope time base for 20 usec/div.
5Use a trimmer tool to adjust the compensation capacitor for the flattest pulse top. See the figure
below for the location of the adjustment.
!
Frequency Compensation Adjustment

3
Safety Precautions
• This high voltage probe must only be used by personnel who are trained, experienced, or
otherwise qualified to recognize hazardous situations and who are trained in the safety
precautions that are necessary to avoid possible injury when using such a device.
• Do not work alone when working with high voltage circuits
• For your own safety, inspect the probes for cracks and frayed or broken leads before each use.
If defects are noted, DO NOT use the probe.
• Hands, shoes, floor and work bench must be dry. Avoid making measurements under humid,
damp or other environmental conditions that might effect the safety of the measurement
situation.
• It is advisable to turn the high voltage source off before connecting or disconnecting the probe.
• The probe body should be kept clean and free of any conductive contamination. Refer to the
section on cleaning.
Operation
1Connect the probe to the BNC input of the oscilloscope.
2Select the desired volts/division range. (If you can set probe attenuation on the oscilloscope,
set it to 1000:1)
3Whenever possible, turn the high voltage source off before making any connections.
4Connect the divider probe ground lead (alligator clip) to a good earth ground or reliable chassis
ground.
5Before turning on the high voltage source, make sure that no part of the person holding the
probe is touching the device under test. Once this is certain, turn on the high voltage source.
6Measure the voltage under test and observe the waveform on the oscilloscope. Remember the
actual voltage is 1000 times greater than the oscilloscope waveform if the probe attenuation
has not been set to 1000:1.
7Turn off the high voltage source
8Disconnect the Agilent N2771A High Voltage Probe from the high voltage source BEFORE
disconnecting the ground clip lead.
WARNING • Do not attempt to take measurements from sources where the chassis or return lead is not
grounded
• The ground lead is critical to the safe operation of the probe. Failure to make this connection
when making high voltage measurements may result in personal injury or damage to the probe
or oscilloscope. This connection must always be made BEFORE the probe tip comes in contact
with the high voltage and must not be removed until the probe tip has been removed from the
high voltage source.
• Do not connect the ground clip lead to the high voltage source for any reason.
• Do not make any floating measurements with the Agilent N2771A High Voltage probe.
Cleaning
• Clean only the exterior probe body and cables. Use a soft cotton cloth lightly moistened with
a mild solution of detergent and water. Do not allow any portion of the probe to be submerged
at any time.
• Dry the probe thoroughly before attempting to make voltage measurements.
• Do not subject the probe to solvents or solvent fumes as these can cause deterioration of the
probe body and cables.
!

4
Manual Part Number
N2771-92001
$
Printed in Malaysia
Agilent Technologies
1900 Garden of the Gods Road
Colorado Springs, Colorado 80907
S1