Greenlee CM-330 User manual

999 5223.8 REV 1 © 2004 Greenlee Textron Inc. 9/04
CM-330
Clamp-on
Ammeter
Amperímetro
con pinza
Pince
ampèremétrique
INSTRUCTION MANUAL
MANUAL DE INSTRUCCIONES
MANUEL D’INSTRUCTIONS
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.

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Description
The Greenlee CM-330 Clamp-on Ammeter is a hand-held testing device
capable of measuring up to 400 amps of alternating current.
Safety
Safety is essential in the use and maintenance of Greenlee tools and
equipment. This instruction 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 of This Manual
This instruction manual is intended to familiarize all personnel with the
safe operation and maintenance procedures for the Greenlee CM-330
Clamp-on Ammeter.
Keep this manual available to all personnel.
Replacement manuals are available upon request at no charge.
KEEP THIS MANUAL
All specifications are nominal and may change as design improvements occur.
Greenlee Textron 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 Textron Inc.

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CM-330
Important Safety Information
Electric shock hazard:
Contact with live circuits could result in severe
injury or death.
Read and understand this material before
operating or servicing this equipment. Failure to
understand how to safely operate this tool could
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.

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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 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 operate with the case or battery door open.
•Before opening the case or battery door, remove the jaw from the
circuit and shut off the unit.
Failure to observe these warnings could result in severe injury or death.
Electric shock hazard:
Using this unit near equipment that generates electromagnetic
interference can result in unstable or inaccurate readings.
Failure to observe this warning could 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.
Refer to “Specifications.”
Failure to observe these precautions may result in injury and can
damage the unit.

5
CM-330
Using the Features
•Data Hold Button Press momentarily to hold the present value on the
display. will appear on the display.
Press again to return to normal mode.
•Max Hold Button Press momentarily to hold the maximum value on the
display. “MAX” will appear on the display. The highest value will remain
on the display, which will update when the meter measures a new
maximum.
Press again to return to normal mode.
Identification
1. Jaw
2. Lever
3. Selector
4. Display
5. Max Hold button
6. Data Hold button
Symbols on the Unit
Warning—Read the instruction manual
Risk of electric shock
Double insulation
Display Icons
7. Data Hold is activated.
8. MAX Max Hold is activated.
9. AC amps
10. Low battery indicator
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