
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 qualied personnel should use this probe. This high voltage
probe is designed to be used by personnel who are trained, experienced,
or otherwise qualied 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 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, oor and work bench must be dry.
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 ngers behind the probe’s nger 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
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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 ofce-type indoor setting
z The instrument is designed to be used in office-type indoor
environments. Do not operate the instrument:
z In the presence of noxious, corrosive, or flammable fumes,
gases, vapors, chemicals, or finely-divided particulates.
z In environments where there is a danger of any liquid being
spilled on the instrument.
z In air temperatures exceeding the specified operating
temperatures.
z 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 specications if the instrument is used
in non-ofce-type environments. Such environments may include rapid
temperature or humidity changes, sunlight, vibration and/or mechanical
shocks, acoustic noise, electrical noise, strong electric elds, or strong
magnetic elds.
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 Cal Test Electronics
or modify this instrument. Return the instrument to Cal Test Electronics
for service and repair to ensure that safety and performance features are
maintained.
WARNING statement calls attention to an operating procedure,
A
practice, or condition, which, if not followed correctly, could result in injury
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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.
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.
Contact Us
If you have a need for calibration or repair services, technical, or sales
support, please contact us:
22820 Savi Ranch Parkway
Yorba Linda, CA 92887
800-572-1028 or 714-221-9330
caltestelectronics.com
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1 Introduction
Overview
The Cal Test CT4026 is an 18 kV High Voltage divider probe for use
with both digital and analog oscilloscopes.
Features
z Measures up to: 18 kV (DC + ACpk) or 12 kVrms AC
z DC to 150 MHz bandwidth
z Voltage dividing of 1000:1
z Frequency compensation
Probe Accessories
Figure 1: CT4026 Probe Accessories
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