TECHNICAL MANUAL CALIBRATION PROCEDURE FOR LCR METER 875A, 875B (B & K PRECISION) This publication replaces T.O. 33K dated 30 August 2011.

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1 TECHNICAL MANUAL CALIBRATION PROCEDURE FOR LCR METER 875A, 875B (B & K PRECISION) This publication replaces T.O. 33K dated 30 August Distribution Statement C - Distribution authorized to U. S. Government agencies and their contractors for official use or for administrative or operational purposes only, 30 September Requests for this document shall be referred to AFMETCAL, 813 Irving-Wick Dr W, Heath, OH Destruction Notice - For unclassified, limited documents, destroy by any method that will prevent disclosure of the contents or reconstruction of the document. Published under Authority of the Secretary of the Air Force 30 OCTOBER 2011

2 LCR METER 875A, 875B (B & K PRECISION) 1 CALIBRATION DESCRIPTION: Table 1. Test Instrument (TI) Performance Test Characteristics Specifications Method Capacitance Range: 875A, 200 p to 2 mf; Compared to a 875B, 200 p to 20 mf Standard Capacitors Accuracy: 875A, 200 pf rng, (3% rdg + 1 dgt); 2 nf to 2 F rngs, (2% rdg + 1 dgt); 20 to 200 F rngs, (3% rdg + 3 dgts); 2 mf rng, (5% rdg + 3 dgts) Zero rdg: 875A 200 pf rng, less than 5 dgts; 2 F rng, less than 3 dgts; 20 nf to 2 mf rng, less than 2 dgts Accuracy: 875B, 200 pf to 200 F rngs, (1% rdg + 2 dgts); 2 and 20 mf rngs, (2% rdg +10 dgts) Resistance Range: 0 to 20 M Compared to a Standard Resistor Accuracy: 875A, 20 rng, (2% rdg + 2 dgts); 200 to 2 M rngs, (0.5% rdg + 1 dgt); 20 M rng, (3% rdg + 1 dgt) Zero rdg: 875A, 20 rng, less than 10 dgts; 200 rng, less than 1 dgt; greater than 200 rng, 0 dgts; 0 reading 10 dgts Accuracy: 875B, 2 rng, (1% rdg + 5 dgts); 20 to 200 k rngs, (1% rdg + 2 dgts); 2 and 20 M rngs, (2% rdg + 2 dgts) 1

3 Table 1. (Cont.) Test Instrument (TI) Performance Test Characteristics Specifications Method Inductance Range: 200 H to 200 H Compared to a Standard Inductor Accuracy: 875A, 200 H rng, (3% rdg + 1 dgt); 2 to 200 mh rngs, (2% rdg + 1 dgt); 2 to 20 H rngs, (3% rdg + 1 dgt); 200 H rng, (5% rdg + 1 dgt) 2 EQUIPMENT REQUIREMENTS: Zero rdg: 875A, 200 H to 200 H rngs, less than 10 dgts Accuracy: 875B, 200 H rng, (2% rdg + 2 dgts); 2 to 200 mh rngs, (1% rdg + 2 dgts); 2 to 200 H rngs, Accuracies are not specified. Ranges are used for reference only Minimum Use Calibration Sub- Noun Specifications Equipment Item 2.1 CAPACITOR SET Range: 100 pf to 1.4 F ARCO SS32 Accuracy: (0.1% pf) of charted value 2.2 CAPACITOR Range: 10 F NSN Accuracy: measured value 2.3 CAPACITOR Range: 100 F NSN Accuracy: measured value 2.4 DECADE Range: 10 to 10 M Shallcross RESISTOR 833 Accuracy: 0.125% of setting 2.5 RESISTANCE Range: 1.9 ESI STANDARD * RS925D Accuracy: 0.25% See footnote at the end of the Equipment Requirements. 2

4 Minimum Use Calibration Sub- Noun Specifications Equipment Item 2.6 STANDARD Range: 100 mh GENRAD INDUCTOR 1482L Accuracy: 0.25% 2.7 RLC DIGIBRIDGE Range: 0 to 100 F General Radio 1689M Accuracy: 0.25% of rdg 2.8 MULTI-FREQUENCY Range: 0 to 100 pf Andeen-Hagerling CAPACITANCE AH2700 BRIDGE * Accuracy: 0.3% of 120 Hz * Required to calibrate P/N 875B. 3 PRELIMINARY OPERATIONS: 3.1 Review and become familiar with the entire procedure before beginning the Calibration Process. WARNING Unless otherwise designated, and prior to beginning the Calibration Process, ensure that all test equipment voltage and/or current outputs are set to zero (0) or turned off, where applicable. Ensure that all equipment switches are set to the proper position before making connections or applying power. If not strictly observed, could result in injury to, or death of personnel or long term health hazards. 3.2 Connect test equipment to an appropriate power source. Set POWER switches to ON and allow warm-up as required by the manufacturer. 3.3 Use only that portion of the Calibration Process that applies to TI being calibrated. 3.4 Connect the test leads to the TI + (red) and - (black) input jacks, observing polarity. 3.5 Set TI (P/N 875A) Function switch to LCR, and select the 20 range. 3.6 Short TI test leads together. The TI (P/N 875A) must indicate 10 counts or less. NOTE All tolerances listed in the Calibration Process for P/N 875A do not include the Zero rdg specification. If applicable, check the Zero rdg for all applicable ranges and subtract the Zero rdg error from reading of measurement. 3.7 Set RLC Digibridge as required, measure Capacitors (2.2) and (2.3) at 120 Hz. Record the measured values for later use. 3.8 For the TI (P/N 875B) calibration, measure the 100 pf capacitor of the Capacitor Set at 120 Hz. Record the measured value for later use. 3

5 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 CAPACITANCE CALIBRATION: Set the TI Function switch to LCR Connect adapters required for calibration to TI test leads and position them so the leads are not touching. NOTE When using the Capacitor Set, use the 4 position Adapter Bar to connect TI to capacitors Select the first TI Range listed in Table 2. Record TI indication for all ranges for P/N 875A, 20 and 200 F ranges only for P/N 875B Select the appropriate capacitor/capacitors for the first corresponding value listed in the Applied column of Table Discharge each capacitor selected and then connect the TI test leads to the capacitor/capacitors The TI must indicate within the corresponding values listed in the Limits column of Table 2. Allow for step recorded indication Disconnect the capacitor/capacitors from TI test leads Repeat steps through for each remaining range and applied value listed in Table 2. Table 2. (875A) (875B) TI Range Applied (µf) Limits (F) Limits (F) 200 pf * to p (1% of Measured value + 2 dgts) 2 nf * to n to n 20 nf * to n to n 200 nf * to n to n 2 F * to to F * 2 10 (3% of Measured value + 3 dgts) (1% of Measured value + 2 dgts) 200 F * (3% of Measured value + 3 dgts) (1% of Measured value + 2 dgts) * 1 For P/N 875B slowly turn the TI 0 Adj control for a zero reading on the display. 4

6 * 2 For P/N 875B, set the TI Range for the 2 F rng, if necessary, and slowly turn the TI 0 Adj control for a zero reading on the display. 4.2 RESISTANCE CALIBRATION: Connect the TI test leads to the Decade Resistor (Resistance Standard for P/N 875B) Select the first TI Range listed in Table Set the Decade Resistor (Resistance Standard for P/N 875B) to the first corresponding value listed in the Applied column of Table The TI must indicate within the corresponding values listed in the Limits column of Table Repeat steps through for each remaining range and applied value listed in Table 3. Table 3. (875A) (875B) TI Range Applied ( ) Limits ( ) Limits ( ) 2 * N/A to * 1, * to to * to to k * to k to k to k to k to k.988 to k to.504 k.493 to.507 k 20 k * k to k to k 200 k * k to k to k 2 M M to M to M 20 M M 9.69 to M 9.78 to M * 1 For P/N 875B, before measurement set Decade Resistor or Resistance Standard to minimum Ω and slowly turn the TI 0 Adj control for a zero reading on the display. * 2 Replace the Resistance Standard with the Decade Resistor for the remaining applied values Disconnect the TI test leads from the Decade Resistor. 5

7 4.3 INDUCTANCE CALIBRATION: Set the TI Function switch to LCR and select TI 200 mh Range. For P/N 875B, connect test leads used for measurement together and slowly turn the TI 0 Adj control for a zero reading on the display Connect the TI test leads to the Standard Inductor The TI must indicate between 97.9 to mh (98.8 to mh for P/N 875B) Set all Power switches to STANDBY/OFF. Disconnect and secure all equipment. CALIBRATION PERFORMANCE TABLE Not Required 6