380942 calibration procedure - user equipuserequip.com/files/specs/6207/380942-external.pdf · this...

DISCLAIMER

Extech recommends the use of our test and measurement calibration services at our facility in Nashua,

NH. We utilize proprietary calibration procedures, which may be provided to our customers as a

courtesy. Use of Extech calibration procedures by anyone other than Extech technicians may void the

factory warranty and is at the user’s own risk.

Written By: _____________________________

Teri M King

Approved By: _____________________________ Date Approved: ______________________

Matt Caffrey

Extech Instruments Corporation

EICM380942-CP August 2012 Revision: 1.0

380942 CALIBRATION PROCEDURE

380942 Calibration Procedure

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Procedure Number: EICM380942-CP


Revision Log

Revision Number

Date Approved

Pages Affected

Description of Revision

Initial February 2008 All Initial Release

1.0 August 2012 5 On page 5, changed the wording in Section 4.1.0.


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Table of Contents

REVISION LOG …………………………………………………………......................... 2

1.0. INTRODUCTION………………………………………………………………....... 4

1.1. Purpose……………………………………………………………………... 4

1.2. Scope / Field of Application……………………………………………….. 4

1.3. Document Security…………………………………………………............. 4

1.4. Document References………………………………………………............ 4

2.0. REQUIRED EQUIPMENT…………………………………………………………. 4

3.0. 380942 ACCURACY TEST…………….…………………………………………... 4

4.0. 380942 CALIBRATION ADJUSTMENTS………………………………………… 5

4.1.0. mADC Zero Adjustment…………………………………………………... 5

4.2.0. 400 VDC Adjustment………………………………………………………. 5

4.3.0. 400 VAC Adjustment……………...……………………………………….. 5

4.4.0. 4000 mAAC Jaw Balance Adjustment………………………….................. 5

4.5.0. 4000 mAAC Zero Adjustment.…………………………………………….. 5

4.6.0. 4000 mAAC Adjustment…..……………………………………………….. 5

4.7.0. 400 mAAC Adjustment……….……………………………………………. 6

4.8.0. 30 AAC Adjustment……….……………………………………………. 6

FIGURE: 1 “Calibration Potentiometers”…………………………………………… 7

APPENDIX: A “Checking Procedure”……………………………………………… 8


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1.0. INTRODUCTION

1.1. Purpose

The purpose of this procedure is to provide detailed instructions on how to test and/or adjust

Extech Instruments Model 380942.

1.2. Scope / Field of Application

This procedure will be used by Extech Instruments Calibration Laboratory for detailed

instructions on how to test and/or adjust Extech Instruments Model 380942.

1.3. Document Security

This document is considered to be proprietary. Therefore, this document may not be

reproduced or transmitted in any form for use outside of Extech Instruments without the

consent of Extech Instruments Corporation.

1.4. Document References

Model 380942 “30A True RMS Clamp Meter” Checking Procedure.

380942 Data Sheet – EICDS380942.

2. REQUIRED EQUIPMENT

The following equipment will be needed to properly calibrate the instrument.

(1) Calibrated Wavetek Universal Calibrator (Model: 9100) or equivalent.

3. 380942 ACCURACY TEST

3.1. Install two (2) “AA” batteries into the instrument.

3.2. Connect the banana to banana test leads to the input socket of the 380942.

3.3. Connect the other end of the banana to banana test leads to the output of the Wavetek 9100.

3.4. Power on and set the 380942 to VDC.

3.5. Set the Wavetek 9100 to DC Voltage.

3.6. Apply 150.0 VDC to the EX470.

NOTE: The instrument should read 150.0 VDC +/- (1.0%rdg+2d)

3.7.Record the EX470 reading on the proper data sheet. (EICDS- EX470)

3.8.For the remaining test points refer to the “Model EX470 – Checking Procedure” listed in

Appendix A.


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NOTE: When calibrating customer owned instruments, technicians must record all of the “as

received” readings on the corresponding data sheet. If the instrument is newly purchased from stock

and does not meet the specified tolerances, proceed to Section: 4. Technicians are not required to

record “Out of Tolerance” indications for newly purchased instruments.

3.9. If any of the readings were outside of the specified tolerances, proceed to Section: 4.

3.10. If all of the readings were within the specified tolerances, the verification is now complete.

380942 CALIBRATION ADJUSTMENTS

NOTE: To access the calibration potentiometers, carefully remove the top faceplate.

4.1.0 mADC Zero Adjustment:

4.1.1. Set the unit to the mAAC Range.

4.1.2. Snap the jaws on the unit a couple times to release any magnetic errors that may be

present.

4.1.3. Apply 0.00 mADC, adjust the “VR6” potentiometer until the unit displays a value of

“0.00”.

4.2.0 400 VDC Adjustment:

4.2.1. Set the unit to the 400 VDC Range.

4.2.2. Apply 200.0 VDC to the meters input sockets.

4.2.3. Adjust the “VR3” potentiometer until the unit displays a value of “200.0”.

4.3.0 400 VAC Adjustment:

4.3.1. Set the unit to the 400 VAC Range.

4.3.2. Apply 200.0 VAC (60.00 Hz) to the unit.


4.4.0 4000 mAAC Jaw Balance Adjustment:

4.4.1. Set the unit to the 4000 mAAC Range.

4.4.2 Apply 2000 mAAC (60.00 Hz) to the clamp meter’s Jaw Sensor.

4.4.3. Adjust the “VR7” and “VR8” until the clamp meters display is stable when the clamp is

moved around.

4.5 4000 mAAC Zero Adjustment:


NOTE: The accuracy of the reading is not important at this time.


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4.5.2. With no input applied adjust the “VR9” potentiometer until the unit displays a value of

“0.0”.

4.6 4000 mAAC Range Adjustment:


4.6.2. Apply 1000 mAAC (60.00 Hz) to the jaw sensor.

4.6.3. Adjust the “VR2” potentiometer until the unit displays a value of “1000”

4.7 400 mAAC Range Adjustment:


4.7.2. Apply 200.0 mAAC (60.00 Hz) to the jaw sensor.


4.8 30 AAC Range Adjustment:

4.8.1 Set the unit to the 30 AAC Range.

4.8.2 Apply 20.00 AAC (60.00 Hz) to the jaw sensor.


NOTE: After all adjustments have been made, proceed to Section: 3 to retest the instrument.

Record the data from Section: 3 as the “Final Reading” of the instrument. If the instrument is

new, record the data as the “Calibration Data”.


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Figure: 1 Calibration Potentiometers

VR7 – AAC Jaw Balance Adjustment

VR6 – mADC Zero Adjustment

VR4 – 400mAAC Adjustment

VR8 – Jaw Balance Adjustment

VR2 – 4000mAAC Adjustment

VR1 – 30AAC Adjustment

VR9 – 4000mAAC Zero

VR3 – 400VDC Adjustment

VR11 – 400VAC Adjustment


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Appendix: A CHECKING PROCEDURE

Page 1 of 1

MODEL 380942

30A True RMS Clamp Meter

1. VISUAL - Check for cosmetic problems, scratches, wrong labels, loose labels, etc.

2. Insert 2 each "1.5V AA" batteries and observe correct polarity.

3. Visually check the display for any missing segments.

4. Test the following functions:

FUNCTION RANGE INPUT TOLERANCE READING NOTES DC Volts 400 V 150.0 V +/- (1.0%rdg+2d) 148.3-151.7 V

400 V 350.0 V +/- (1.0%rdg+2d) 346.3-353.7 V

AC Volts 400 V 150.0 V +/- (2.0%rdg+5d) 146.5-153.5 V *test @ 40 to 1KHz.

400 V 150.0 V +/- (1.5%rdg+4d) 147.4-152.7 V *test @ 50/60 Hz.

400 V 350.0 V +/- (1.5%rdg+4d) 344.4-355.7 V

DC Current 4000 mA 750 mA +/- (2.0%rdg+3d) 732-768 mA

4000 mA 3500 mA +/- (2.0%rdg+3d) 3427-3573 mA

30 A 10.00 A +/- (2.0%rdg+3d) 9.77-10.23 A

30 A 25.00 A +/- (2.0%rdg+3d) 24.47-25.53 A

AC Current 400 mA 150.0 mA +/- (2.0%rdg+5d) 146.5-153.5 mA *test @ 40/100 Hz

400 mA 150.0 mA +/- (1.5%rdg+5d) 147.2-152.8 mA *test @ 50/60 Hz

400 mA 350.0 mA +/- (1.5%rdg+5d) 344.2-355.8 mA

4000 mA 1500 mA +/- (3.0%rdg+5d) 1450-1550 mA *test @ 40 to 1KHz

4000 mA 1500 mA +/- (2.5%rdg+5d) 1458-1543 mA *test @ 50/60 Hz

4000 mA 3500 mA +/- (2.5%rdg+5d) 3408-3593 mA

30 A 10.00 A +/- (2.0%rdg+5d) 9.75-10.25 A

30 A 25.00 A +/- (2.0%rdg+5d) 24.45-25.55 A

30 A 25.00 A +/- (2.5%rdg+5d) 24.33-25.68 A *test @ 40 to 1KHz

5. Re-pack the instrument and check for:

test leads,

manual,

case.

380942 calibration procedure - user equipuserequip.com/files/specs/6207/380942-external.pdf · this...

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