Fluke 374, 375, 376 Operating Manual

Users Manual

374/375/376

Clamp Meter

PN 3608883 July 2010

LIMITED WARRANTY AND LIMITATION OF LIABILITY

This Fluke product will be free from defects in material and workmanship for three years from the date of purchase. This warranty does not cover fuses, disposable batteries, or damage from accident, neglect, misuse, alteration, contamination, or abnormal conditions of operation or handling. Resellers are not authorized to extend any other warranty on Fluke’s behalf. To obtain service during the warranty period, contact your nearest Fluke authorized service center to obtain return authorization information, then send the product to that Service Center with a description of the problem.

THIS WARRANTY IS YOUR ONLY REMEDY. NO OTHER WARRANTIES, SUCH AS FITNESS FOR A PARTICULAR PURPOSE, ARE EXPRESSED OR IMPLIED. FLUKE IS NOT LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LOSSES, ARISING FROM ANY CAUSE OR THEORY. Since some states or countries do not allow the exclusion or limitation of an implied warranty or of incidental or consequential damages, this limitation of liability may not apply to you.

Fluke Corporation P.O. Box 9090 Everett, WA 98206-9090 U.S.A.

11/99

Fluke Europe B.V. P.O. Box 1186 5602 BD Eindhoven The Netherlands

Title Page

Introduction................................................................................................................. 1

How to Contact Fluke ................................................................................................. 2

Safety Information ...................................................................................................... 3

The Meter ................................................................................................................... 9

Specifications ............................................................................................................. 19

Electrical Specifications.......................................................................................... 19

Mechanical Specifications ...................................................................................... 26

Environmental Specifications ................................................................................. 27

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Users Manual

Introduction

XWWarning

Read "Safety Information" before you use the Meter.

The Fluke 374, 375, and 376 (the Meter) measure true-rms ac current and voltage, dc current and voltage, inrush current, resistance, and capacitance. The 375 and 376 also measure frequency and dc millivolts. The detachable iFlex (Flexible Current Probe) that is included with the 376 (optional with the 374 and 375) expands the measurement range to 2500 A ac. The Flexible Current Probe provides increased display flexibility and allows measurements of awkward sized conductors and improved wire access. The illustrations in this manual show the 376.

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Users Manual

How to Contact Fluke

To contact Fluke, call one of the following telephone numbers:

• Technical Support USA: 1-800-44-FLUKE (1-800-443-5853)

• Calibration/Repair USA: 1-888-99-FLUKE (1-888-993-5853)

• Canada: 1-800-36-FLUKE (1-800-363-5853)

• Europe: +31 402-675-200

• Japan: +81-3-3434-0181

• Singapore: +65-738-5655

• Anywhere in the world: +1-425-446-5500

Or, visit Fluke's website at www.fluke.com

To register your product, visit http://register.fluke.com

To see, print, or download the latest manual supplement, visit

http://us.fluke.com/usen/support/manuals

Clamp Meters

Safety Information

A Warning identifies conditions and actions that pose hazard(s) to the user. A Caution identifies conditions and procedures that could cause Meter damage, equipment under test damage, or permanent loss of data.

Symbols used on the Meter and in this manual are explained in Table 1.

XWWarning

To prevent possible electrical shock or personal injury, follow these guidelines:

• Use the Meter only as specified in this manual or the protection provided by the

Meter can be compromised.

• Examine the case before you use the Meter. Look for cracks or missing plastic.

Carefully look at the insulation around the connectors.

• Never measure current while the test leads are inserted into the input jacks.

• Make sure the battery door is closed and latched before operating the Meter.

• Remove the test leads from the Meter before the battery door is opened.

• Examine the test leads for damaged insulation or exposed metal. Check test lead

continuity. Replace damaged test leads before using the Meter.

• Do not use the Meter if it operates incorrectly. Protection can be compromised.

When in doubt, have the Meter serviced.

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Users Manual

• Do not use the Meter around explosive gas, vapor or in damp or wet

environments.

• Use only type AA batteries, properly installed in the Meter case, to power the

Meter.

• When measuring current with the Jaw, keep fingers behind the Tactile Barrier.

See "The Meter" .

• To avoid false readings that can lead to electrical shock and injury, replace the

batteries as soon as the low battery indicator () appears.

• When servicing the Meter, use only specified replacement parts.

• Have the Meter serviced only by qualified service personnel.

• Be careful around voltages > 30 V ac rms, 42 V ac peak, or 60 V dc. Such

voltages pose a shock hazard.

• Do not apply more than the rated voltage, as marked on the Meter, between the

terminals or between any terminal and earth ground.

• When using the probes, keep fingers behind the finger guards on the probes.

• Connect the common test lead before connecting the live test lead. When

disconnecting test leads, disconnect the live test lead first.

• Do not work alone so assistance can be rendered in an emergency.

• Use extreme caution when working around bare conductors or bus bars. Contact

with the conductor could result in electric shock.

Clamp Meters

Safety Information

• Adhere to local and national safety codes. Individual protective equipment must

be used to prevent shock and arc blast injury where hazardous live conductors are exposed.

• Disconnect circuit power and discharge all high-voltage capacitors before you

measure resistance, continuity, or capacitance.

• For the 374 and 375, do not measure ac/dc current in circuits carrying more than

1000 V or 600 A with the Meter Jaw.

• For the 376, do not measure ac/dc current in circuits carrying more than 1000 V

or 1000 A with the Meter Jaw.

• Never operate the Meter with the back cover removed or the case open.

• Do not measure ac current in circuits carrying more than 1000 V or 2500 A with

the Flexible Current Probe.

• Do not apply the Flexible Current Probe around or remove from HAZARDOUS

LIVE conductors.

• Do not use the flexible current sensor if the inner contrasting insulation color is

showing.

• Take special care during fitting and removal of the Flexible Current Probe. De-

energize the installation under test or wear suitable protective clothing.

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Users Manual

WCaution

To avoid possible damage to the Meter or to equipment under test:

• Use the proper jacks, function, and range for the measurement application.

• Clean the case and accessories with a damp cloth and mild detergent only.

Do not use abrasives or solvents.

Table 1. Symbols

Symbol Meaning Symbol Meaning

B AC (Alternating Current)

F DC (Direct Current) ~

X Hazardous voltage P

Earth ground

Do not dispose of this product as unsorted municipal waste. Go to Fluke’s website for recycling information.

Conforms to European Union directives.

+ 22 hidden pages

Fluke 374, 375, 376 Operating Manual

Table of Contents

Introduction

How to Contact Fluke

Safety Information