Greenlee 5990A User manual

52084986 © 2018 Greenlee Tools, Inc. 8/18
Read and understand all of the instructions and safety information in this
manual before operating or servicing this tool.
Lea y entienda todas las instrucciones y la información sobre seguridad
que aparecen en este manual, antes de manejar esta herramienta o
darle mantenimiento.
Lire attentivement et bien comprendre toutes les instructions et les
informations sur la sécurité de ce manuel avant d'utiliser ou de procéder
à l'entretien de cet outil.
INSTRUCTION MANUAL
INSTRUCTION MANUAL
MANUAL DE INSTRUCCIONES
MANUEL D'INSTRUCTIONS
5990A
Megohmmeter
Megóhmetro
Megohmmetre
Español.................. 26
Français................. 50

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Table of Contents
Description .............................................................................................. 3
Safety ...................................................................................................... 3
Purpose.................................................................................................... 3
Important Safety Information............................................................... 4–6
Identification.......................................................................................7-11
LC Display ......................................................................................... 7
Operator’s Panel................................................................................ 8
Connectors.................................................................................. 9–10
High Voltage Shielded Test Tips with High Voltage Alligator Clips... 11
Performing Measurements.............................................................. 12–13
Measurements................................................................................. 14–18
General Information About DC High Voltage Testing........................ 14
Guard Terminal................................................................................ 15
Insulation Resistance Measurement......................................... 16–17
Voltage Measurement ..................................................................... 18
Maintenance.................................................................................... 19–21
Specifications................................................................................. 22–23
Accuracy ......................................................................................... 22
Measurements ................................................................................ 22
Insulation Resistance...................................................................... 22
General Capability vs Resistance.................................................... 23
Voltage ............................................................................................ 23
General Specifications........................................................................... 24
Measurement Categories ...................................................................... 25
Statement of Conformity ....................................................................... 25

5990A
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Description
The Greenlee 5990A Megohmmeter is intended to test insulation and detect voltage. The unit
features an easy-to-read and accurate analog scale.
Safety
Safety is essential in the use and maintenance of Greenlee tools and equipment. This instruc-
tion manual and any markings on the tool provide information for avoiding hazards and unsafe
practices related to the use of this tool. Observe all of the safety information provided.
Purpose
This instruction manual is intended to familiarize all personnel with the safe operation and
maintenance procedures for Greenlee 5990A Megohmmeter.
Keep this manual available to all personnel.
Replacement manuals are available upon request at no charge.
Greenlee and are registered trademarks of Greenlee Tools, Inc.
Do not discard this product or throw away!
For recycling information, go to www.greenlee.com.
All specifications are nominal and may change as design improvements occur. Greenlee Tools, Inc. shall not be liable for
damages resulting from misapplication or misuse of its products.
® Registered: The color green for electrical test instruments is a registered trademark of Greenlee Tools, Inc.
KEEP THIS MANUAL

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Important Safety Information
Read and understand this material before operating or servicing this
equipment. Failure to understand how to safely operate this tool can
result in an accident causing serious injury or death.
This symbol is used to call your attention to hazards or unsafe practices which could
result in an injury or property damage. The signal word, defined below, indicates the
severity of the hazard. The message after the signal word provides information for
preventing or avoiding the hazard.
SAFETY ALERT SYMBOL
Immediate hazards which, if not avoided, WILL result in severe injury or death.
Hazards which, if not avoided, COULD result in severe injury or death.
Hazards or unsafe practices which, if not avoided, MAY result in injury or
property damage.
Electric shock hazard:
Contact with live circuits can result in severe injury or death.

5990A
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Important Safety Information
Electric shock and fire hazard:
• Do not expose this unit to rain or moisture.
• Do not use the unit if it is wet or damaged.
• Use test leads or accessories that are appropriate for the application. See the category and
voltage rating of the test lead or accessory.
• Inspect the test leads before use. They must be clean and dry, and the insulation must be in
good condition.
• Use this unit for the manufacturer’s intended purpose only, as described in this manual.
Anyotheruse can impair the protection provided by the unit.
Failure to observe these warnings could result in severe injury or death.
Electric shock hazard:
• Do not apply more than the rated voltage between any two input terminals, or between any
input terminal and earth ground.
• Do not contact the test lead tips or any uninsulated portion of the accessory.
• Do not contact the test lead tips while performing the insulation resistance test.
Failure to observe these warnings could result in severe injury or death.
Electric shock hazard:
• Do not operate with the case open.
• Before opening the case, remove the test leads from the circuit and shut off the unit.
Failure to observe these warnings could result in severe injury or death.
Electric shock hazard:
• Unless measuring voltage, shut off and lock out power. Make sure that all capacitors are
discharged. Voltage must not be present.
• Using this unit near equipment that generates electromagnetic interference can result in
unstable or inaccurate readings.
Failure to observe these warnings could result in severe injury or death.

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Working with the instrument:
• Equipment under test must be switched off (i.e. de-energized) before test leads are con-
nected to the equipment.
• Do not touch any conductive parts of equipment under test during the test.
• Make sure that the tested object is disconnected (mains voltage disconnected) before start-
ing the Insulation Resistance measurement!
• Do not touch the tested object whilst testing it, risk of electric shock!
• In case of a capacitive test object (long tested cable etc.), automatic discharge of the object
may not be done immediately after finishing the measurement – “Please wait, discharging”
message will be displayed.
Handling with capacitive loads:
• Note that 40 nF charged to 1 kV or 9 nF charged to 5 kV are hazardous live!
• Never touch the measured object during the testing until it is totally discharged.
• Maximum external voltage between any two leads is 600 V (CAT IV environment).
Important Safety Information
Electric shock hazard:
Contact with live circuits can result in severe injury or death.
Electric shock hazard:
• Do not attempt to repair this unit. It contains no user-serviceable parts.
• Do not expose the unit to extremes in temperature or high humidity. See Specifications.
Failure to observe these precautions may result in injury and can damage the unit.

5990A
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Instrument Description
Instrument Casing
The instrument is housed in a plastic box that maintains the protection class defined in the
general specifications.
LCD
The LCD has a backlight and offers easy-to-read results. See Fig.1 below.
Legend:
1.......... Battery indicator: This indicates condition of the battery. In battery charging mode it flashes.
2.......... Hazardous Voltage Warning icon: This indicates that voltage higher than 70 V may be
present at the test terminals!
3.......... Analog display
4.......... Auxiliary digital display
5.......... Auxiliary units
6.......... Analog units
7.......... Bar graph
8.......... Warning icon: Carefully read and understand the User Manual.
9.......... Pass or Fail icon
10........ Main units
11........ Main digital display
12........ Test voltage: Menu for selecting the test voltage.
Fig. 1 LCD Display

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5990A Megohmmeter
5990A
52085064 REV1
The operator’s panel is shown in Fig. 2 below.
Legend:
1...........Ω: Press to switch to Insulation Measurement Mode. Press again to set a resistance
limit value.
2.......... V: Press to switch to Voltage measurement mode.
3.......... Light:Press to to turn the display backlight ON or OFF.
4.......... tcursor: Press to decrease the test voltage parameter or resistance limit value.
5.......... ucursor: Press to increase the test voltage parameter or resistance limit value.
6.......... START/STOP: Press to start or stop insulation measurement.
7.......... ON/OFF: Press to switch the instrument ON or OFF.
Fig. 2. Front Panel
Operator’s Panel
Instrument Description (cont’d)
LCD
Keypad4 5
6
7
1
2
3

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The 5990A Tester contains the following connections:
• Four banana safety sockets for test leads (Fig. 3).
• Socket for mains supply cable (Fig. 4).
Fig. 3 Test Leads Connector Diagram
Connectors
1.......... (-OUT): Negative Insulation Resistance test terminal
2.......... GUARD: Guard terminals are intended to lead away potential leakage current while
measuring the Insulation. Both green sockets are connected together inside of
the instrument.
3.......... (+OUT): Positive Insulation Resistance test terminal
Use original test accessories only!
Max allowed external voltage between test terminals and ground is 600V!
Max allowed external voltage between test terminals is 600V!
Instrument Description (cont’d)
1 2 3

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Fig. 4. Mains connector
Fig. 4 Mains Connector
Connectors (cont’d)
1..........Mains connector: This is to connect the instrument to the mains supply.
Use original mains supply cable only!
Instrument Description (cont’d)