TABLE OF CONTENTS SECTION I INTRODUCTION AND DESCRIPTION

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1 Walter G. LEGGE Co., Inc. 444 Central Ave., Peekskill, NY tel # fax address: info@leggesystems.com website: TABLE OF CONTENTS SECTION PAGE 1 INTRODUCTION AND DESCRIPTION EQUIPMENT REQUIREMENTS PRELIMINARY OPERATION CALIBRATION PROCESS OHM METER TEST MAXIMUM CURRENT TEST NAVY CALIBRATION CHECKLIST... 5 SECTION I INTRODUCTION AND DESCRIPTION 1.1. This procedure describes the calibration of the Walter G. LEGGE Company, Inc. models SLTM M. The instrument being calibrated is referred to herein as the TI (Test Instrument). 1.2 This procedure was prepared by Mr. D. C. Burton of the Metrology Engineering Center. All comments concerning this procedure should be directed to the Metrology Engineering Center, Naval Plant Representative Office, Pomona, California. Use of a Calibration Problem Report card is recommended. 1.3 This procedure includes tests of essential performance parameters only. Any malfunctions noticed during calibration, whether specifically tested for or not should be corrected.

2 TABLE 1. CALIBRATION DESCRIPTION TI PERFORMANCE TEST Characteristics Specifications Method OHM METER Range: 0 to 10 The TI meter indication Scale division: 0,100k, will be compared to a 250k, 500k, 1M ohm, and decade resistor with an Tolerance: +3% or +1/16 uncertainty of better of an inch at 1M than +0.75% CURRENT Range: 0.5 ma Measured with a voltohm-amp meter SECTION 2 EQUIPMENT REQUIREMENTS NOTE Minimum use specifications are the principal parameters required for performance of the calibration, and are included to assist in the selection of alternate equipment, which may be used at the discretion of the using laboratory. Satisfactory performance of alternated items shall be verified prior to use. All applicable equipment must bear evidence of current calibration. The instruments utilized in this procedure were selected from those known to be available at Department of Defense facilities, and the listing by make or model number carries no implication of preference, recommendation, or approval by the equipment produced by other manufactures may be capable of equally satisfactory performance in the procedure. ITEM MINIMUM USE CALIBRATION SPECIFICATIONS EQUIPMENT 2.1 Decade resistor Range: 0 to 1.111M ohm General Radio 1433B Uncertainty: +0.75% or 1432B 2.2 Test leads Clip leads to banana Pomona Electronics plug,12 inch long, or local 18 AWG supply 2.3 Volt-Ohm- Current range:0 to 1mA Simpson 270-4, Amp meter dv or 260 (VOM) Uncertainty: +2% of FS

3 SECTION 3 PRELIMINARY OPERATIONS 3.1 Adjust the TI meter mechanical adjustment control to set the meter pointer to the extreme left of the meter red scales. 3.2 Apply power to the TI by connection the TI line cord to the appropriated power source. Allow 10 minutes for warm up. 3.3 Depress and hold the TI red pushbutton switch on the meter housing, and verify that the meter pointer moves up scale, to the right, and stops at rest on 0, if not, adjust the screwdriver control located next to the red pushbutton switch for a precise 0 indication. 3.4 Release the red push Button switch to open the TI meter zero circuit. SECTION 4 CALIBRATION PROCESS NOTE Unless otherwise specified, verify the results of each test and take corrective action whenever the test requirement is not met, before proceeding. 4.1 OHM METER TEST Using the clip test leads (item 2.2) connect the decade resistor to the TI. Figure 1: OHM METER TEST SETUP

4 4.1.2 Set the decade resistor as required to position the TI meter pointer to each of the values listed below. The decade resistor setting at each indication must be within the tolerance limits listed. TI METER INDICATION (ohms) DECADE RESISTOR TOLERANCE LIMITS (ohms) 100k to k to k to Set the decade resistor to 1M ohm and verify that the TI meter pointer indicates 1M +1/16 of an inch Set the decade resistor to 1.111M ohm and verify that the TI meter pointer moves into the red area of the meter Disconnect the test leads from the decade resistor. 4.2 MAXIMUM CURRENT TEST Set the VOM range switch to 1 ma dc and connect the lead from the left shoe plate to the + terminal and the lead from the right shoe plate to the - terminal of the VOM The maximum dc current indication on the VOM should be 0.5 ma dc If no other measurements are to be performed, disconnect the TI line cord from the power outlet, and disconnect the test equipment from the TI.

5 PROCEDURE STEP NO. (1) FUNCTION TESTED (2) NOMINAL (3) MEASURED VALUES (4) OUT OF TOL (6) CALIBRATION TOLERANCES (7) 3.1 METER SET EXTREME L.H. SCALE 3.3 METER ZERO SET ADJUST AS REQUIRED 4.1 OHM METER TEST GREEN AREA 100 " " 250 (OHMS) TO TO " " RED - GREEN AREA 1 Mohms RED AREA Mohms CK () TO ± 1/16 INCH IN RED AREA 4.2 CURRENT TEST VOM INDICATION 0.5 ma 0.5 to 0.6 ma MAX.