381 Remote Display True-rms Clamp Meter Users Manual PN 3538357 July 2010 © 2010 Fluke Corporation. All rights reserved. Printed in China. Specifications are subject to change without notice. All product names are trademarks of their respective companies.
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.
Table of Contents Title Page Introduction................................................................................................................. How to Contact Fluke ................................................................................................. Safety Information ...................................................................................................... Radio Frequency Data .............................................................................................
381 Users Manual Display.................................................................................................................... Measurements............................................................................................................ AC and DC Current (Jaw) ...................................................................................... AC Current (Flexible Current Probe) ...................................................................... AC and DC Voltage ..............
List of Tables Table 1. 2. 3. 4. 5. Title Page Symbols.............................................................................................................. Meter Features ................................................................................................... Rotary Function Switch ...................................................................................... Display................................................................................................................
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List of Figures Figure 1. 2. 3. 4. 5. 6. 7. 8. 9. Title Page Remote Display .................................................................................................. Meter Features ................................................................................................... Display................................................................................................................ Current Measurement with Jaw.......................................................................
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Introduction Warning Read "Safety Information" before you use the Meter. The Fluke 381 is a handheld, battery-operated Clamp Meter (the Meter) that has a remote-display module and detachable iFlex (Flexible Current Probe). The Remote Display can be removed from the Meter body and read away from the measurement source. This lets the display be easily read in difficult-measurement situations such as a hazardous environments, or very tight spaces.
381 Users Manual 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.
Remote Display True-rms Clamp Meter Safety Information 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. Do not use the Meter around explosive gas, vapor or in damp or wet environments.
381 Users Manual 4 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. Adhere to local and national safety codes.
Remote Display True-rms Clamp Meter Safety Information Caution To avoid possible damage to the Meter or to equipment under test: Use the proper jacks, function, and range for the measurement application. Table 1. Symbols Symbol Meaning Symbol Meaning Earth ground DC (Direct Current) Hazardous voltage Conforms to European Union directives. Risk of Danger. Important information. See Manual. Conforms to relevant North American Safety Standards. Battery.
381 Users Manual Symbol Meaning CAT III IEC Measurement Category III CAT III equipment has protection against transients in equipment in fixed-equipment installations, such as distribution panels, feeders and short branch circuits, and lighting systems in large buildings. Symbol Meaning CAT IV Examined and licensed by TÜV Product Services. Conforms to relevant Australian standards. Do not apply to or remove from HAZARDOUS LIVE conductors.
Remote Display True-rms Clamp Meter Radio Frequency Data Radio Frequency Data Note Changes or modifications to the wireless 2.4 GHz radio not expressly approved by Fluke Corporation could void the user's authority to operate the equipment. This device complies with Part 15 of the FCC Rules. Operation is subject to the two conditions that follow: 1. This device can not cause interference. 2. This device must accept any interference, including interference that can cause undesired operation of the device.
381 Users Manual off and on, the user is encouraged to try to correct the interference by one or more of the measures that follow: Reorient or relocate the receiving antenna. Increase the separation between the equipment and receiver. Consult the dealer or an experienced radio/TV technician for help. The term "IC:" before the radio certification number only signifies the device meets Industry's Canada technical specifications. Features The following sections explain the Meter features in detail.
Remote Display True-rms Clamp Meter Features The display module is synchronized with a Meter base when it is docked on the Meter base and turned on. Different display modules can be synchronized with a Meter base but, only one display module can be synchronized to a Meter base at the same time. The Meter base and display can be a maximum of 10 meters from each other before the radio signal connection is broken. This distance can change with the obstacles between the Meter base and display.
381 Users Manual Hazardous Voltage Indicator When the Meter senses a voltage 30 V or a voltage overload (OL), is shown on the display and the red high-voltage LED () on the Meter base illuminates to tell you a hazardous voltage is at the Meter input. Flexible Current Probe Warning To avoid electrical shock, do not apply or remove from live hazardous conductors.
Remote Display True-rms Clamp Meter Features Backlight Push to toggle the Backlight on and off. The Backlight automatically goes off after 2 minutes. To disable the Backlight Auto Off feature, hold down while turning on the Meter. Display Hold To capture and hold the present display reading, push while taking a reading. Push again to return to the live reading. MIN MAX AVG Min Max Avg mode can capture the minimum, maximum, and average readings of a given output signal over an extended time.
381 Users Manual Inrush Inrush Current is surge current that occurs when an electrical device is first powered on. The Meter can capture this surge current reading. Current spikes from motor drives are one example of such an event. The Inrush function takes approximately 400 samples over a 100 ms period and calculates the starting current envelope. Low Battery Indicators The Meter uses two low battery symbols: and . When appears, the batteries in the Meter base should be changed.
Remote Display True-rms Clamp Meter Features 2 1 3 5 6 7 CAT 1000 V CAT 600 V ZERO iFlex REMOTE DISPLAY 381 TRMS CLAMP METER 1000 A 4 16 14 11 13 10 9 8 12 15 ghn02.eps Figure 2.
381 Users Manual Table 2. Meter Features Item 14 Description Current sensing Jaw Tactile Barrier Rotary Function Switch, see Table 3. Hazardous-voltage indicator Display release button Display Backlight button: turns the Backlight on and off. The Backlight stays on for 2 minutes when there is no button or switch interaction and then shuts off. Hold button: freezes the display reading and releases the reading when pushed a second time.
Remote Display True-rms Clamp Meter Features Item Description Zero/Shift button: removes dc offset from dc current measurements. Also used to shift and corresponds to the yellow items on the Rotary Function Switch. Inrush button: push to enter inrush mode. Push a second time to exit inrush mode. Integration time is 100 ms. Jaw release Alignment marks: to meet accuracy specifications, the conductor must be aligned with these marks.
381 Users Manual Table 3. Rotary Function Switch Switch Position OFF AC voltage DC voltage 16 Function Meter is powered down Resistance and continuity AC current. Push to shift to frequency. DC current AC current and frequency measurement using the Flexible Current Probe. Push to shift to frequency.
Remote Display True-rms Clamp Meter Features Display To view all segments on the display at once, push while turning the Meter on. See Figure 3 and Table 4. 2 1 3 15 4 14 5 13 12 6 11 10 9 8 7 ghn01.eps Figure 3.
381 Users Manual Table 4. Display Item 18 Description Inrush is active Item Description Meter base low-battery symbol Hold is active Measurement is taken at the Jaw. Volts RF signal is being sent to remote display. Amps Continuity Ohms, DC, AC, Hz Hazardous voltage is present. Main display Measurement is taken at the Flexible Current Probe. Remote display low-battery symbol Min, Max, or Avg reading is being shown. Min Max mode is active.
Remote Display True-rms Clamp Meter Measurements Measurements Note Prior to first use, remove the battery isolator (small piece of plastic between the batteries and battery contacts). AC and DC Current (Jaw) Warning To avoid electric shock or personal injury: When making current measurements, disconnect the test leads from the Meter. Keep fingers behind Tactile Barrier. See Figure 2 and Table 2. Note When measuring current, center the conductor in the Jaw using the alignment marks on the Jaw.
381 Users Manual Note Before zeroing the Meter, make sure the Jaws are closed and there is no conductor inside the Jaw. To measure ac or dc current: 1. Turn the Rotary Function Switch to the proper function. You should see on the display, indicating that the measurement is coming from the Jaw. Note When the measured current is < 0.5 A, the center dot in the display icon will flash on and off. With current > 0.5 A, the center dot will be steady. 2. 3. 4. 5.
Remote Display True-rms Clamp Meter Measurements C 10 AT CA 0 0 V 60 T 0V CAT 1000 V CAT 600 V 1000 A 10 38 1 00 A R TR EMO MS TE CL DISP AM LA PM Y E TE R iFle x ghn04.eps Figure 4.
381 Users Manual AC Current (Flexible Current Probe) Warning To prevent possible electrical shock or personal injury: Do not apply the Flexible Current Probe around or remove from HAZARDOUS LIVE conductors. Take special care during fitting and removal of the Flexible Current Probe. De-energize the installation under test or wear suitable protective clothing. To use the Flexible Current Probe, follow these instructions: 1. Connect the Flexible Current Probe to the Meter. See Figure 5. 2.
Remote Display True-rms Clamp Meter Measurements 4. . When the Rotary Function Switch is in the correct Turn the Rotary Function Switch to position, shows on the display, meaning that the readings are coming from the Flexible Current Probe. Note When the measured current is < 0.5 A, the center dot in the display icon () will flash on and off. With current > 0.5 A, the center dot will be steady. 5. Observe the current value on the Meter display.
381 Users Manual ghn09.eps Figure 5.
Remote Display True-rms Clamp Meter Measurements ghn05.eps Figure 6.
381 Users Manual Resistance/Continuity To measure resistance or continuity: 1. Turn the Rotary Function Switch to . 2. Remove power from the circuit being tested. 3. Connect the black test lead to the COM terminal and the red test lead to the terminal. 4. Measure the resistance by touching the probes to the desired test points of the circuit. 5. View the reading on the display. If the resistance is < 30 , continuity is indicated by a beeper continuously sounding.
Remote Display True-rms Clamp Meter Measurements Off CAT 1000 V CAT 600 V 3 On 100 ms 1000 A 1 REMOTE DISPLAY 381 TRMS CLAMP METER CAT 1000 V CAT 600 V 1000 A REMOTE DISPLAY 381 TRMS CLAMP METER iFlex INRUSH 4 2 ghn11.eps Figure 7.
381 Users Manual Frequency Measurement (Jaw and Flexible Current Probe) To measure frequency: 1. Turn the Meter Rotary Function Switch to or if the Flexible Current Probe is being used for the measurement. 2. Center the Jaw or Flexible Current Probe around the measurement source. 3. Push on the Meter to shift to Hz. The frequency is displayed on the Meter display.
Remote Display True-rms Clamp Meter Maintenance Clean the instrument case with a damp cloth and mild detergent. Battery Replacement To replace the batteries in the Meter body, see Figure 8: 1. Turn the Meter OFF. 2. Use a flat head screwdriver to loosen the battery compartment door screw on the Meter base, and remove the door from the case bottom. 3. Remove the batteries. 4. Replace the batteries with three new AAA batteries. 5. Reattach the battery compartment door to the case bottom and tighten the screw.
1 Users Manual ghn03.eps Figure 8.
Remote Display True-rms Clamp Meter User-Replaceable Parts User-Replaceable Parts Table 5. User-Replaceable Parts Description Qty. Fluke Part Number Battery, AAA 1.
381 Users Manual Specifications Electrical Specifications AC Current Via Jaw Range ..................................................... 999.9 A Resolution ............................................... 0.1 A Accuracy ................................................. 2 % 5 digits (10-100 Hz) 5 % 5 digits (100-500 Hz) Crest Factor (50/60 Hz) .......................... 3 @ 500 A 2.5 @ 600 A 1.42 @1000 A Add 2 % for C.F.
Remote Display True-rms Clamp Meter Specifications AC Current via Flexible Current Probe Range .....................................................999.9 A / 2500 A (45 Hz – 500 Hz) Resolution ...............................................0.1 A / 1 A Accuracy .................................................3 % 5 digits Crest Factor (50/60Hz) ...........................3.0 at 1100 A 2.5 at 1400 A 1.42 at 2500 A Add 2 % for C.F.
381 Users Manual Position Sensitivity A B C ghn12.eps Figure 9.
Remote Display True-rms Clamp Meter Specifications Distance from Optimum i2500-10 Flex i2500-18 Flex Error A 0.5 in (12.7 mm) 1.4 in (35.6 mm) 0.5 % B 0.8 in (20.3 mm) 2.0 in (50.8 mm) 1.0 % C 1.4 in (35.6 mm) 2.5 in (63.5 mm) 2.0 % Measurement uncertainty assumes centralized primary conductor at optimum position, no external electrical or magnetic field, and within operating temperature range. DC Current Range .....................................................999.9 A Resolution .
381 Users Manual DC Voltage Range ..................................................... 600.0 V /1000 V Resolution ............................................... 0.1 V / 1 V Accuracy ................................................. 1 % 5 digits Frequency – Via Jaw Range ..................................................... 5.0 – 500.0 Hz Resolution ............................................... 0.1 Hz Accuracy ................................................. 0.5 % 5 digits Trigger Level ..........
Remote Display True-rms Clamp Meter Specifications Frequency via Flexible Current Probe Range .....................................................5.0 to 500.0 Hz Resolution ...............................................0.1 Hz Accuracy .................................................0.5 % 5 digits Trigger Level ...........................................5 to 20 Hz, 25 A 20 to 100 Hz, 20 A 100 to 500 Hz, 25 A Resistance Range .....................................................
381 Users Manual Flexible Current Probe Cable Length (head to electronics connector) .............. 1.8 m Environmental Specifications Operating Temperature........................... -10 C to +50 C Storage Temperature.............................. -40 C to +60 C Operating Humidity ................................. Non condensing (< 10 C) 90 % RH (at 10 C to 30 C) 75 % RH (at 30 C to 40 C) 45 % RH (at 40 C to 50 C) (Without Condensation) Operating Altitude ..................................
Remote Display True-rms Clamp Meter Specifications FCC Part 15 Subpart C Sections 15.207, 15.209, 15.249 FCCID: T68-F381 RSS-210 IC: 6627A-F381 Temperature Coefficients Add 0.1 x specified accuracy for each degree C above 28 C or below 18 C Wireless Frequency ................................2.4 GHz ISM Band 10 meter range Safety Compliance..................................ANSI/ISA S82.02.01:2004 CAN/CSA-C22.2 No. 61010-1-04 IEC/EN 61010-1:2001 to 1000V CAT III, 600V CAT IV. Double Insulation Clearance..
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