374/375/376 Clamp Meter Calibration Manual December 2010 © 2010 Fluke Corporation. All rights reserved. Specifications are subject to change without notice. All product names are trademarks of their respective companies.
LIMITED WARRANTY AND LIMITATION OF LIABILITY Each Fluke product is warranted to be free from defects in material and workmanship under normal use and service. The warranty period is three years and begins on the date of shipment. Parts, product repairs, and services are warranted for 90 days.
Table of Contents Title Introduction........................................................................................................ Contact Fluke..................................................................................................... Safety Information ............................................................................................. The Meter........................................................................................................... Specifications...........
374/375/376 Calibration Manual ii
List of Tables Table 1. 2. 3. 4. 5. Title Symbols.................................................................................................................. Performance Tests .................................................................................................. Required Equipment............................................................................................... Adjustment Procedure ............................................................................................
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List of Figures Figure Title 1. 2. 3. 4. 5. The Meter ............................................................................................................... Position Sensitivity................................................................................................. Calibration Activation ............................................................................................ Current Calibration Setup...................................................................................
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Introduction XWWarning Read "Safety Information" before you use the Product. This manual explains the Calibration Adjustment for the 374, 375, and 376 Clamp Meters (the Product). Please see the 374/375/376 Users Manual for usage information.
374/375/376 Calibration Manual 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 Product and in this manual are explained in Table 1.
Clamp Meter Safety Information • Use caution around bare conductors or bus bars. To prevent electrical shock, do not touch the conductor. • Comply with local and national safety codes. Use personal protective equipment (approved rubber gloves, face protection, and flame-resistant clothes) to prevent shock and arc blast injury where hazardous live conductors are exposed. • Disconnect power and discharge all high-voltage capacitors before you measure resistance or continuity.
374/375/376 Calibration Manual Table 1. Symbols Symbol B Meaning AC (Alternating Current) Symbol Meaning J Earth ground F DC (Direct Current) ~ Do not dispose of this product as unsorted municipal waste. Go to Fluke’s website for recycling information. X Hazardous voltage P Conforms to European Union directives. W Risk of Danger. Important information. See Manual. ) Conforms to relevant North American Safety Standards. Battery. Low battery when shown on display.
Clamp Meter The Meter The Meter Clamp Meter fig01.eps Figure 1. The Meter Specifications Electrical Specifications AC Current via Jaw Range 374 and 375 ...................................... 600.0 A 376..................................................... 999.9 A Resolution ............................................... 0.1 A Accuracy ................................................. 2 % ± 5 digits (10-100 Hz) 2.5 % ± 5 digits (100-500 Hz) Crest Factor (50/60 Hz) ..........................
374/375/376 Calibration Manual Position Sensitivity A B C ghn12.eps Figure 2. Position Sensitivity 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 374 and 375 ..........
Clamp Meter Specifications DC Voltage Range 374 and 375 ........................................ 600.0 V 376 ...................................................... 1000 V Resolution 374 and 375 ........................................ 0.1 V 376 ...................................................... 0.1 V (≤ 600.0 V) 1 V (≤ 1000 V) Accuracy ................................................. 1 % ± 5 digits mV dc Range 375 and 376....................................... 500.0 mV Resolution ....................
374/375/376 Calibration Manual Mechanical Specifications Size (L x W x H) ..................................... 246 mm x 83 m x 43 mm Weight..................................................... 388 g Jaw Opening ........................................... 34 mm Flexible Current Probe Diameter ............ 7.5 mm Flexible Current Probe Cable Length (head to electronics connector) .............. 1.8 m Environmental Specifications Operating Temperature...........................
Clamp Meter Performance Tests Performance Tests XWWarning To prevent possible electrical shock, fire, or personal injury, do not perform the performance test procedures unless the Product is fully assembled. The following performance tests verify the complete operation of the Product and check the accuracy of each function against the Product’s specifications. See Table 2. If the Product fails any part of the test, calibration adjustment and/or repair is indicated. See “Calibration Adjustment”. Table 2.
374/375/376 Calibration Manual Table 2. Performance Tests (cont.) Test (Switch Position) ? AC Amps (with 50turn Coil) DC Amps (with 50turn Coil) iFlex Current Probe (with Simulation) iFlex Current Probe (with 50turn Coil) Meter Reading Limit Calibrator Output 374 375 376 Low High 0.2 A @ 50 Hz X X X 9.7 A 10.3 A 10 A @ 50 Hz X X X 495.0 A 505.0 A 18 A @ 5 0Hz - - X 891.0 A 909.0 A 6 A @ 440 Hz X X X 296.0 A 304.0 A 0.2 A X X X 9.7 A 10.3 A 10 A X X X 495.
Clamp Meter Calibration Adjustment Adjustment Procedure To adjust Product calibration: 1. Turn the Product over to access the battery compartment door screw. 2. Use a flat-head screwdriver to loosen the battery compartment door screw and lift off the battery compartment door. See Figure 5. 3. Remove the calibration sticker. 4. Connect the Power Supply to the Product battery terminals. 5. Turn the Product ON. 6. Use a small jumper to short the two pads together under the calibration sticker.
374/375/376 Calibration Manual 5522A CALIBRATOR NORMAL V, , ,RTD AUX A, -SENSE, AUX V SCOPE OUT STBY HI 7 LO TRIG 4 GUARD 20A 1 +/ 20V PK MAX Figure 4. Current Calibration Setup The calibration adjustment is complete. When the adjustment is complete: 1. Remove the Power Supply. 2. Replace the batteries. 3. Reattach the battery compartment door. 4. Tighten the battery compartment door screw. 12 TC 20V PK MAX ghn50.
Clamp Meter Calibration Adjustment Table 4. Adjustment Procedure Test (Switch Position) LCD Reading 374 375 376 Calibrator Output K C-00 X X X 600 V @ 50 Hz AC Volts C-01 X X X 300 V @ 50 Hz C-02 X X X 300 V @ 100 Hz C-03 X X X 300 V @ 200 Hz C-04 X X X 300 V @ 300 Hz C-05 X X X 300 V @ 400 Hz C-06 X X X 300 V @ 500 Hz Save X X X STBY L C-07 X X X 0V DC Volts C-08 X X X 600 V C-09 X X X 0V C-10 X X X 0.
374/375/376 Calibration Manual Table 4. Adjustment Procedure (cont.
Clamp Meter Maintenance Maintenance Clean the Product WCaution To prevent possible damage to the Product or to equipment under test, do not use abrasive cleaners. They will damage the case. To clean the Product, use a cloth with a mild cleaning solution. Battery Replacement XW Warning To prevent possible explosion, fire, or personal injury, replace the batteries when the low battery indicator () shows to prevent incorrect measurements.
374/375/376 Calibration Manual 3 1 2 fig11_12.eps Figure 5. Changing the Batteries User Replaceable Parts User replaceable parts are listed in Table 5. Table 5. User Replaceable Parts Fluke Part Number 16 Description Qty 3845988 Battery Door Assembly 1 3752958 Soft Case 1 3608883 User Manual 1 376756 Battery (AA 1.
