MEASURING INSTRUMENTS CATALOG No.E2019
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D-42DMitutoyo reserves the right to change any or all aspects of any product specication, including prices, designs and service content, without notice.DMaximum Permissible Error of partial measuring surface contact error EMPE [JIS B 7507: 2016]The partial measuring surface contact error of a caliper is an indication error applied to the outside measurement.Table 1 shows the Maximum Permissible Error EMPE of the indication value of the partial measuring surface contact error.The value can be obtained by inserting a gauge block, or an equivalent orhigher gauge, between the outside measuring surfaces (Fig. 3), measuring the different position along the jaw at an arbitrary position in the measuring range and then subtracting the dimension of the gauge from the indicated value.Scale Shift Error SMPE [JIS B 7507: 2016]The scale shift error in a caliper is an indication error of the inside measurement, depth measurement, etc., if a measuring surface other than the outside measuring surface is used.The Maximum Permissible Error SMPE of the indication value of the inside measurement equals a value indicated in Table 1. The Maximum Permissible Error SMPE of the depth measurement is obtained by adding 0.02 mm to a value indicated in Table 1.The indication error of the inside measurement can be obtained by measuring the inside dimensions with the inside measuring surface of a gauge block, or using an equivalent or higher gauge, at an arbitrary position in the measuring range (Fig. 4), and then subtracting the dimension of the gauge from the indicated value.Performance evaluation method for the caliperJIS B 7507 was revised and issued in 2016 as the Japanese Industrial Standards of the caliper, and the “Instrumental error” indicating the indication error of the caliper has been changed to “Maximum Permissible Error (MPE) of indication”.The “Instrumental error” of the old JIS adopts acceptance criteria that the specication range (precision specication) equals acceptance range, and the OK/NG judgment does not include measurement uncertainty. (Fig. 1)The “Maximum Permissible Error (MPE) of indication” of the new JIS adopts the basic concept of the OK/NG judgment taking into account the uncertainty adopted in the ISO standard (ISO 14253-1).The verication of conformity and nonconformity to the specications is clearly stipulated to use the internationally recognized acceptance criteria (simple acceptance) when the specication range equals the acceptance range, and it is accepted that the specication range equals the acceptance range if a given condition considering uncertainty is met.In this case, the internationally recognized acceptance criterion is ISO/TR 14253-6:2012. (Fig. 2)The following describes the standard inspection method including the revised content of JIS 2016.Fig. 1Fig. 2Old JIS Instrumental errorJIS B 7507-1993 Conformity rangeUncertainty is not included in judgmentSpecication range=Acceptance rangeSpecication rangeAcceptance rangeNon-conformity rangeNon-conformity rangeNew JIS Maximum Permissible Error (MPE)JIS B 7507: 2016 (ISO/TR 14253-6: 2012)When a condition considering uncertainty is satisedSpecication range=Conformity rangeNon-conformity rangeNon-conformity rangeConformity rangeSpecication rangeUncertaintyrangeUncertaintyrangeU(Rejected)(Rejected)AcceptedUUUUnit: mmMeasurement lengthScale interval, graduation or resolution0.050.0250 or less± 0.05± 0.02Over 50, 100 or less± 0.06± 0.03Over 100, 200 or less± 0.07Over 200, 300 or less± 0.08± 0.04Note: EMPE includes the measurement error arising from the straightness, flatness and parallelism of the measuring surface.Table 1: Maximum Permissible Error EMPE of partial measuring surface contact errorGauge blockGauge blockFig. 3: Measurement of partial measuring surface contact errorFig. 4: Measurement of scale shift error (inside measurement)The “Instrumental error” indicating the indication error of JIS has been changed to “Maximum Permissible Error (MPE) of indication” in the following three models:• 530 Series M-Shape Standard Caliper described in D-11 (530-101 530-108 530-109)• 532 Series M-Shape Fine-feed Caliper described in D-13 (All models)• 531 Series M-Shape Automatic Stop Caliper described in D-13 (All models)

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