B+K precision PR-55 User manual

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Model: PR-55
High Voltage
Oscilloscope Probe
10 kV, 40 MHz
USER MANUAL

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© 2017 All rights reserved.
B&K Precision products are covered by US and
foreign patents, issued and pending. Information is
this publication supersedes all earlier versions.
Specifications subject to change without notice.
For product information, sales, service, and
technical support:
•Call 1-714-921-9095 or visit: bkprecision.com
Compliance Statements
Disposal of Old
Electrical & Electronic
Equipment
(Applicable in the European Union
and other European countries with
separate collection systems). This
product is subject to Directive
2012/19/EU of the European
Parliament and the Council of the European Union
on waste electrical and electronic equipment
(WEEE), and in jurisdictions adopting that Directive,
is marked as being put on the market after August
13, 2005, and should not be disposed of as
unsorted municipal waste. Please utilize your local
WEEE collection facilities in the disposition of this
product and otherwise observe all applicable
requirements.

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Safety Summary
WARNING CAUTION
To avoid personal injury and/or product damage,
review and comply with the following safety precautions.
These precautions apply to both operating and
maintenance personnel and must be followed during all
phases of operation, service, and repair of this instrument.
Only qualified personnel should use this probe. This
high voltage probe is designed to be used by personnel
who are trained, experienced, or otherwise qualified to
recognize hazardous situations and who are trained in the
safety precautions necessary to avoid possible injury
when using such a device.
This instrument is intended for usage within
Measurement Category I (CAT I) only.
Do not exceed 60 seconds of contact with high
voltage. When making contact between this probe and
any circuit with voltages ≥8 kV DC, ≥5 kVrms AC, or ≥15
kVpk-pk AC, wait for 5 minutes between such
measurements.
Do not work alone when working with high voltages.
Do not apply to the input any potential that exceeds
the maximum rating of the probe.
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.

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Avoid making measurements under humidity,
dampness or other environmental conditions that might
affect safety.
Turn the high voltage source off before connecting or
disconnecting the probe whenever possible.
The probe body should be kept clean and free of any
conductive contamination.
Do not remove the probe casing. Removal of the
probe’s casing may expose you to electric shock.
Keep fingers behind the probe’s finger guard during
use.
Always properly ground the probe with the lead before
contacting high voltage circuits with the probe tip. Always
disconnect the probe tip from high voltage circuits before
disconnecting the ground lead. Do not connect the probe
ground lead to any point which is at a potential other than
earth ground.
Use only on test instruments where the chassis or
return lead is properly grounded.
Use only in office-type indoor setting
The instrument is designed to be used in office-type
indoor environments. Do not operate the instrument:
•In the presence of noxious, corrosive, or
flammable fumes, gases, vapors, chemicals, or
finely-divided particulates.
•In environments where there is a danger of any
liquid being spilled on the instrument.
•In air temperatures exceeding the specified
operating temperatures.

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•In atmospheric pressures outside the specified
altitude limits or where the surrounding gas is
not air.
Use in an indoor Pollution Degree 2 environment.
Measurements made by this instrument may be outside
specifications if the instrument is used in non-office-type
environments. Such environments may include rapid
temperature or humidity changes, sunlight, vibration
and/or mechanical shocks, acoustic noise, electrical
noise, strong electric fields, or strong magnetic fields.
Not for critical applications. This instrument is not
authorized for use in contact with the human body or for
use as a component in a life-support device or system.
Hazardous voltages may be present in unexpected
locations in circuitry being tested when a fault condition
in the circuit exists.
Do not substitute parts that are not approved by B&K
Precision or modify this instrument. Return the instrument
to B&K Precision for service and repair to ensure that
safety and performance features are maintained.
AWARNING statement calls attention to an operating
procedure, practice, or condition, which, if not followed
correctly, could result in injury or death to personnel.
A CAUTION statement calls attention to an operating
procedure, practice, or condition, which, if not followed
correctly, could result in damage to or destruction of parts
or the entire product.

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1 General Information
1.1 Product Overview
The B&K Precision PR-55 is a 10 kV High
Voltage divider probe for use with both
digital and analog oscilloscopes.
1.2 Features
•Measure up to: 10kV (DC + ACpk)or
7kVrms AC
•40 MHz bandwidth
•Voltage dividing of 1000:1
•Frequency compensation
2 Using the Probe
1. Connect the probe to the BNC
input of the oscilloscope.
2. Select the desired volts/division
range on your oscilloscope.
3. If possible, always turn the high
voltage source off before
connecting or disconnecting the
probe.
4. Connect the divider probe
ground lead (alligator clip) to a
good earth ground or reliable
chassis ground.
5. Before turning on the high
voltage source, be certain the
operator is not touching any
part of the device under test.
6. Turn on the high voltage
source.

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7. You will now be able to analyze
the voltage waveform on your
oscilloscope.
8. Turn off the high voltage
source.
9. Disconnect the High Voltage
Probe from the high voltage
source BEFORE disconnecting
the ground clip lead.
WARNING
Do not exceed 60 seconds of contact
between this probe and any circuit with
voltages ≥8 kV DC, ≥5 kVrms AC, or ≥15
kVpk-pk AC. Wait for 5 minutes between
such measurements.
3 Frequency Compensation
Proper compensation of the probe is
required to assure amplitude accuracy of
the waveform being measured by matching
the probe to the oscilloscope’s input
capacitance. Compensation should be
adjusted whenever the probe is connected
to, or transferred between, oscilloscopes.
The procedure is the same as for a x10
passive probe.
•Connect the probe to the
oscilloscope.
•Connect probe tip to square-wave
generator.
•Adjust the square wave generator for
10 V amplitude.

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•Adjust the oscilloscope for a time
base of 500 µs/div.
•Turn trimmer (Figure 1) to adjust the
compensation on the probe making a
flat pulse top.
Figure 2 shows how over- and under-
compensated pulse responses will look.
Figure 2: Over/Under Compensation
Figure 1: Trimmer on BNC

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Figure 3 shows a perfectly compensated
probe.
Figure 3: Good Compensation

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4 Specifications
All specifications apply to the unit after a
temperature stabilization time of 15 minutes over an
ambient temperature range of 25 °C ± 5 °C.
PR-55
10 kV High Voltage Probe
Operating Parameters
Maximum Input Voltage
(CAT I)
10 kV (DC + ACpk)
7 kVrms AC
Division Ratio
1000:1
Bandwidth
40 MHz (-3 dB)
Compensation Range
5 pF to 50 pF
Temperature Coefficient
≤200 ppm/ºC
Input Resistance
100 MΩ± 5%
Rise Time
≤8.8 ns
Accuracy
DC Volts
±3% (below 10 kV)
AC Volts
±3% at 1 kHz
±3 dB 0 to 40 MHz
General
Cable Length
6.6 ft (2 m)
Designed for Use in
Pollution Degree 2
Operating Environment
32ºF to 122ºF (0ºC to 50ºC)
Storage Temperature
-4ºF to 158ºF (-20ºC to 70ºC)
Humidity
≤80% relative humidity at
104ºF (40ºC)
Dimensions
13 in (34 cm)
Weight
0.55 lbs (250 g)
Specifications are subject to change without notice.
To ensure the most current version of this manual,
please download the current version from our
website: bkprecision.com.

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5 Voltage Derating Curve
WARNING
When measuring higher frequency signals,
be sure to comply with the Voltage vs
Frequency Derating Curve.
6 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.
WARNING
Dry the probe thoroughly before attempting to
make voltage measurements.
CAUTION Do not subject the probe to
solvents or solvent fumes as these can cause
deterioration of the probe body and cables.
Figure 4: Voltage Derating Curve

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B&K Precision
22820 Savi Ranch Parkway
Yorba Linda, CA 92887
800-462-9832 or 714-921-9095
bkprecision.com
©2017 B&K Precision