B57891M0473K000

NTC thermistors for temperature measurement Leaded NTC thermistors, lead spacing 2.5 mm Series/Type: Date: B57891M February 2009 © EPCOS AG 2009. Reproduction, publication and dissemination of this publication, enclosures hereto and the information contained therein without EPCOS' prior express consent is prohibited. Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Applications Temperature measurement and compensation Features Wide resistance range Cost-effective Lacquer-coated thermistor disk Leads: copper-clad Fe wire, tinned Marked with resistance and tolerance Options Lead spacing 5 mm available on request Delivery mode Bulk (standard), cardboard tape, reeled or in Ammo pack on request Dimensional drawing Dimensions in mm Approx. weight 0.2 g General technical data Climatic category Max. power Resistance tolerance Rated temperature Dissipation factor Thermal cooling time constant Heat capacity (IEC 60068-1) (at 25 °C) 40/125/56 200 ±5, ±10 25 approx. 3.5 approx. 12 approx. 40 (in air) (in air) P25 ∆RR/RR TR δth τc Cth mW % °C mW/K s mJ/K Please read Cautions and warnings and Important notes at the end of this document. Page 2 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Electrical specification and ordering codes R25 Ω 1k 1.5 k 2.2 k 3.3 k 4.7 k 6.8 k 10 k 15 k 22 k 33 k 47 k 68 k 100 k 150 k 220 k 330 k 470 k + = Resistance tolerance J = ±5% K = ±10% No. of R/T characteristic 1009 1008 1013 2003 2003 2003 4901 2004 2904 2904 4012 4012 4003 2005 2005 2007 2006 B25/100 K 3930 ±3% 3560 ±3% 3900 ±3% 3980 ±3% 3980 ±3% 3980 ±3% 3950 ±3% 4100 ±3% 4300 ±3% 4300 ±3% 4355 ±3% 4355 ±3% 4450 ±3% 4600 ±3% 4600 ±3% 4830 ±3% 5000 ±3% Ordering code B57891M0102+000 B57891M0152+000 B57891M0222+000 B57891M0332+000 B57891M0472+000 B57891M0682+000 B57891M0103+000 B57891M0153+000 B57891M0223+000 B57891M0333+000 B57891M0473+000 B57891M0683+000 B57891M0104+000 B57891M0154+000 B57891M0224+000 B57891M0334+000 B57891M0474+000 Reliability data Test Storage in dry heat Standard IEC 60068-2-2 Test conditions ∆R25/R25 (typical) < 3% Remarks No visible damage Storage in damp heat, steady state Rapid temperature cycling Endurance Long-term stability (empirical value) Storage at upper category temperature T: 125 °C t: 1000 h IEC Temperature of air: 40 °C 60068-2-78 Relative humidity of air: 93% Duration: 56 days IEC Lower test temperature: 40 °C 60068-2-14 Upper test temperature: 125 °C Number of cycles: 100 Pmax: 200 mW t: 1000 h Temperature: 70 °C t: 10000 h < 2% No visible damage No visible damage No visible damage No visible damage < 2% < 3% < 5% Please read Cautions and warnings and Important notes at the end of this document. Page 3 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 R/T characteristics R/T No. T (°C) 55.0 50.0 45.0 40.0 35.0 30.0 25.0 20.0 15.0 10.0 5.0 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0 90.0 95.0 100.0 105.0 110.0 115.0 120.0 125.0 130.0 135.0 140.0 145.0 150.0 155.0 1008 1009 1013 B25/100 = 3560 K B25/100 = 3930 K B25/100 = 3900 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 53.104 39.318 29.325 22.03 16.666 12.696 9.7251 7.5171 5.8353 4.5686 3.605 2.8665 2.2907 1.8438 1.492 1.2154 1.0000 0.82976 0.68635 0.57103 0.48015 0.40545 0.3417 0.28952 0.24714 0.21183 0.18194 0.1568 0.13592 0.11822 0.1034 0.090741 0.079642 0.070102 0.061889 0.054785 0.048706 0.043415 0.038722 0.034615 0.031048 0.02791 0.025193 6.1 6.0 5.8 5.7 5.5 5.4 5.2 5.1 4.9 4.8 4.7 4.5 4.4 4.3 4.1 4.0 3.9 3.8 3.7 3.6 3.5 3.4 3.3 3.2 3.1 3.1 3.0 2.9 2.8 2.8 2.7 2.6 2.6 2.5 2.4 2.4 2.3 2.3 2.2 2.2 2.1 2.1 2.0 85.423 60.781 43.65 31.629 23.118 17.04 12.649 9.4864 7.1545 5.4479 4.1732 3.2256 2.5147 1.9763 1.5649 1.2481 1.0000 0.80956 0.65726 0.53697 0.44169 0.36534 0.30327 0.25313 0.21271 0.17962 0.15219 0.12949 0.11067 0.094952 0.08178 0.07069 0.061383 0.053486 0.04673 0.040955 0.036006 0.031747 0.028097 0.024935 0.022176 0.019772 0.017683 7.0 6.8 6.6 6.4 6.2 6.1 5.9 5.8 5.6 5.4 5.2 5.1 4.9 4.8 4.6 4.5 4.3 4.2 4.1 4.0 3.9 3.8 3.7 3.5 3.4 3.4 3.3 3.2 3.1 3.0 3.0 2.9 2.8 2.7 2.7 2.6 2.5 2.5 2.4 2.4 2.3 2.3 2.2 77.285 54.938 39.507 28.722 21.099 15.652 11.715 8.8541 6.7433 5.1815 4.0099 3.1283 2.4569 1.9438 1.5475 1.2403 1.0000 0.81104 0.66146 0.54254 0.44727 0.37067 0.30865 0.25825 0.21707 0.18323 0.15535 0.13223 0.11302 0.096951 0.083487 0.072139 0.062559 0.054425 0.047508 0.041594 0.036532 7.0 6.7 6.5 6.3 6.1 5.9 5.7 5.6 5.4 5.2 5.1 4.9 4.8 4.6 4.5 4.4 4.3 4.1 4.0 3.9 3.8 3.7 3.6 3.5 3.4 3.3 3.3 3.2 3.1 3.0 3.0 2.9 2.8 2.8 2.7 2.6 2.6 Please read Cautions and warnings and Important notes at the end of this document. Page 4 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 R/T No. T (°C) 160.0 165.0 170.0 175.0 180.0 185.0 190.0 195.0 200.0 205.0 210.0 215.0 220.0 225.0 230.0 235.0 240.0 245.0 250.0 1008 1009 1013 B25/100 = 3560 K B25/100 = 3930 K B25/100 = 3900 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 0.02279 2.0 0.020667 2.0 0.01878 0.01709 0.015582 0.014227 0.013012 0.011934 0.010964 0.0101 0.0093191 0.0085949 0.0079384 0.0073411 0.006798 0.0063087 0.0058623 0.0054487 0.0050705 1.9 1.9 1.8 1.8 1.8 1.7 1.7 1.7 1.6 1.6 1.6 1.5 1.5 1.5 1.5 1.4 1.4 Please read Cautions and warnings and Important notes at the end of this document. Page 5 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 R/T characteristics R/T No. T (°C) 55.0 50.0 45.0 40.0 35.0 30.0 25.0 20.0 15.0 10.0 5.0 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0 90.0 95.0 100.0 105.0 110.0 115.0 120.0 125.0 130.0 135.0 140.0 145.0 150.0 155.0 2003 2004 2005 B25/100 = 3980 K B25/100 = 4100 K B25/100 = 4600 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 97.578 67.65 47.538 33.831 24.359 17.753 13.067 9.7228 7.3006 5.5361 4.2332 3.266 2.5392 1.9902 1.5709 1.2492 1.0000 0.80575 0.65326 0.5329 0.43715 0.36064 0.29908 0.24932 0.20886 0.17578 0.14863 0.12621 0.10763 0.092159 0.079225 0.068356 0.059247 0.051531 0.044921 0.039282 0.034387 0.030186 0.02665 0.023594 0.020931 0.018616 0.016612 7.5 7.2 7.0 6.7 6.5 6.3 6.0 5.8 5.6 5.5 5.3 5.1 5.0 4.8 4.7 4.5 4.4 4.3 4.1 4.0 3.9 3.8 3.7 3.6 3.5 3.4 3.3 3.2 3.1 3.1 3.0 2.9 2.8 2.8 2.7 2.7 2.6 2.5 2.5 2.4 2.4 2.3 2.3 Page 6 of 23 99.552 68.582 47.963 34.019 24.448 17.787 13.083 9.7251 7.316 5.5545 4.2531 3.2836 2.5512 1.9973 1.5738 1.2488 1.0000 0.8008 0.64733 0.52628 0.43263 0.35708 0.29406 0.24342 0.20278 0.16964 0.14257 0.12028 0.10196 0.086757 0.073804 0.062974 0.054276 0.046943 0.040576 0.035174 0.030637 7.6 7.3 7.0 6.7 6.5 6.3 6.1 5.8 5.6 5.4 5.3 5.1 5.0 4.8 4.7 4.5 4.5 4.3 4.2 4.0 3.9 3.9 3.8 3.7 3.6 3.5 3.4 3.4 3.3 3.3 3.2 3.0 2.9 3.0 2.9 2.8 2.7 120.22 85.48 61.004 43.712 31.459 22.746 16.49 12.071 8.8455 6.5446 4.8852 3.6781 2.7944 2.1391 1.6507 1.2823 1.0000 0.78393 0.61822 0.49053 0.39116 0.31371 0.25338 0.20565 0.16762 0.13726 0.11279 0.093053 0.077177 0.064263 0.053678 0.044996 0.037917 0.032063 0.027161 0.023079 0.01968 7.0 6.9 6.8 6.7 6.6 6.6 6.4 6.3 6.1 6.0 5.8 5.6 5.4 5.3 5.1 5.1 5.0 4.8 4.7 4.6 4.5 4.3 4.2 4.2 4.1 4.0 3.9 3.8 3.7 3.6 3.6 3.5 3.4 3.4 3.3 3.2 3.2 Please read Cautions and warnings and Important notes at the end of this document. Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Please read Cautions and warnings and Important notes at the end of this document. Page 7 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 R/T characteristics R/T No. T (°C) 55.0 50.0 45.0 40.0 35.0 30.0 25.0 20.0 15.0 10.0 5.0 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0 90.0 95.0 100.0 105.0 110.0 115.0 120.0 125.0 130.0 135.0 140.0 145.0 150.0 155.0 2006 2007 2904 B25/100 = 5000 K B25/100 = 4830 K B25/100 = 4300 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 200.55 131.02 87.171 58.988 40.545 28.272 19.997 14.292 10.35 7.5614 5.5343 4.086 3.0374 2.276 1.7188 1.3074 1.0000 0.76988 0.5954 0.46341 0.36327 0.28636 0.2262 0.17974 0.1438 0.1156 0.093296 0.075623 0.061619 0.050414 0.041532 0.034355 0.028525 0.023774 0.019852 0.016632 0.014016 8.7 8.3 8.0 7.7 7.4 7.1 6.9 6.6 6.4 6.4 6.2 6.0 5.9 5.7 5.6 5.5 5.3 5.2 5.1 4.9 4.8 4.8 4.7 4.5 4.4 4.3 4.3 4.2 4.1 3.9 3.8 3.8 3.7 3.7 3.6 3.5 3.4 185.87 123.23 82.888 56.544 39.061 27.321 19.326 13.823 10.001 7.3067 5.3454 3.9484 2.9595 2.2358 1.7001 1.3021 1.0000 0.7756 0.60507 0.47498 0.37533 0.29823 0.23763 0.19041 0.15356 0.12442 0.10131 0.08286 0.068004 0.056032 0.046379 0.038533 0.032169 0.026952 0.022658 0.019111 0.016201 8.4 8.1 7.8 7.6 7.3 7.1 6.8 6.6 6.4 6.4 6.2 5.9 5.7 5.6 5.4 5.4 5.2 5.0 4.9 4.8 4.7 4.6 4.5 4.4 4.3 4.2 4.1 4.0 3.9 3.8 3.8 3.7 3.6 3.5 3.4 3.3 3.3 121.46 84.439 59.243 41.938 29.947 21.567 15.641 11.466 8.451 6.2927 4.7077 3.5563 2.7119 2.086 1.6204 1.2683 1.0000 0.7942 0.63268 0.5074 0.41026 0.33363 0.27243 0.2237 0.18459 0.15305 0.12755 0.10677 0.089928 0.076068 0.064524 0.054941 0.047003 0.040358 0.034743 0.030007 0.026006 0.022609 0.01972 0.017251 0.015139 0.013321 0.011754 Page 8 of 23 7.4 7.2 7.1 6.9 6.7 6.6 6.3 6.2 6.0 5.9 5.7 5.5 5.3 5.1 5.0 4.8 4.7 4.6 4.5 4.3 4.2 4.1 4.0 3.9 3.8 3.7 3.6 3.5 3.4 3.3 3.3 3.2 3.1 3.0 3.0 2.9 2.8 2.8 2.7 2.6 2.6 2.5 2.5 Please read Cautions and warnings and Important notes at the end of this document. Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Please read Cautions and warnings and Important notes at the end of this document. Page 9 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 R/T characteristics R/T No. T (°C) 55.0 50.0 45.0 40.0 35.0 30.0 25.0 20.0 15.0 10.0 5.0 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0 90.0 95.0 100.0 105.0 110.0 115.0 120.0 125.0 130.0 135.0 140.0 145.0 150.0 155.0 4003 4012 4901 B25/100 = 4450 K B25/100 = 4355 K B25/100 = 3950 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 103.81 73.707 52.723 37.988 27.565 20.142 14.801 10.976 8.1744 6.1407 4.6331 3.5243 2.6995 2.0831 1.6189 1.2666 1.0000 0.78351 0.62372 0.49937 0.40218 0.32557 0.26402 0.21527 0.17693 0.14616 0.12097 0.10053 0.083761 0.070039 0.058937 0.049777 0.042146 0.035803 0.030504 0.026067 0.022332 0.019186 0.016515 0.014253 0.012367 0.010758 0.0093933 6.8 6.7 6.6 6.5 6.4 6.2 6.1 5.9 5.8 5.7 5.5 5.4 5.3 5.1 5.0 4.9 4.7 4.6 4.5 4.4 4.3 4.2 4.1 4.0 3.9 3.8 3.7 3.7 3.6 3.5 3.4 3.4 3.3 3.2 3.2 3.1 3.0 3.0 2.9 2.9 2.8 2.8 2.7 Page 10 of 23 115.76 80.102 56.067 39.677 28.374 20.496 14.949 11.004 8.1721 6.1208 4.6219 3.5176 2.6973 2.0834 1.6205 1.2689 1.0000 0.79302 0.63266 0.50765 0.40961 0.33229 0.27096 0.22206 0.18287 0.1513 0.12574 0.10496 0.087977 0.074045 0.062565 0.053067 0.045177 0.038597 0.03309 0.028464 0.024564 7.5 7.2 7.0 6.8 6.6 6.4 6.2 6.0 5.9 5.7 5.5 5.4 5.2 5.1 5.0 4.8 4.7 4.6 4.5 4.3 4.2 4.1 4.0 3.9 3.8 3.7 3.7 3.6 3.5 3.4 3.3 3.3 3.2 3.1 3.0 3.0 2.9 87.89 61.759 43.934 31.618 23.006 16.915 12.555 9.4143 7.1172 5.4308 4.1505 3.2014 2.5011 1.9691 1.5618 1.2474 1.0000 0.808 0.6569 0.5372 0.44235 0.3661 0.30393 0.25359 0.21283 0.17942 0.15183 0.12901 0.11002 0.094179 0.080896 0.069722 0.060397 0.052493 0.045733 0.039963 0.035059 0.030844 0.027192 0.024034 0.021285 0.018895 0.016813 7.1 6.9 6.7 6.5 6.3 6.1 5.9 5.7 5.5 5.4 5.2 5.0 4.9 4.7 4.6 4.5 4.3 4.2 4.1 4.0 3.9 3.8 3.7 3.6 3.5 3.4 3.3 3.2 3.1 3.1 3.0 2.9 2.9 2.8 2.7 2.7 2.6 2.6 2.5 2.4 2.4 2.4 2.3 Please read Cautions and warnings and Important notes at the end of this document. Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Please read Cautions and warnings and Important notes at the end of this document. Page 11 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Taping and packing 1 Taping of radial leaded NTC thermistors Dimensions and tolerances Lead spacing F = 2.5 mm and 5.0 mm (taping to IEC 60286-2) Dimensions (mm) Lead spacing 2.5 mm 11.0 5.0 0.5/0.6 12.7 5.1 2.5 0 0 18.0 5.5 9.0 3.0 18.0 16.0 32.2 4.0 0.9 11.0 4.0 Lead spacing 5 mm 11.5 6.0 0.5/0.6 12.7 3.85 5.0 0 0 18.0 5.5 9.0 3.0 18.0 16.0 32.2 4.0 0.9 11.0 4.0 Tolerance of lead spacing 2.5/5 mm max. max. ±0.05 ±0.3 ±0.7 +0.6/ 0.1 ±2.0 ±1.3 ±0.5 min. +0.75/ 0.5 max. +2.0/ 0 ±0.5 max. ±0.2 max. max. max. Remarks b s d P0 P1 F ∆h ∆p W W0 W1 W2 H H0 H1 D0 t L L1 ±1 mm / 20 sprocket holes measured at top of component body peel-off force ≥5 N without wires Please read Cautions and warnings and Important notes at the end of this document. Page 12 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Types of packing Ammo packing Ammo type I x 80 y 240 z 210 Packing unit: 1000 - 2000 pcs./reel Reel packing Packing unit: 1000 - 2000 pcs./reel Reel dimensions (in mm) Reel type I II d 360 max. 500 max. f 31 ±1 23 ±1 Page 13 of 23 n approx. 45 approx. 59 w 54 max. 72 max. Please read Cautions and warnings and Important notes at the end of this document. Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Cassette packing Packing unit: 1000 - 2000 pcs./cassette Bulk packing The components are packed in cardboard boxes, the size of which depends on the order quantity. Please read Cautions and warnings and Important notes at the end of this document. Page 14 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 2 Packing codes The last two digits of the complete ordering code state the packing mode: Last two digits 00, 01, 02, 03,04, 05, 06, 07, 08 40 45 50 51 52 53 54 55 60 62 70 72 Radial leads, kinked Radial leads, kinked Radial leads, straight Radial leads, straight Radial leads, kinked Radial leads, straight SMD SMD SMD SMD Bulk Bulk Bulk Cardboard tape Cardboard tape Cardboard tape Cardboard tape Cardboard tape Cardboard tape Cardboard tape Blister tape Cardboard tape Blister tape Cassette packing 360 or 500-mm reel packing Cassette packing 360 or 500-mm reel packing AMMO packing AMMO packing 180-mm reel packing 180-mm reel packing 330-mm reel packing 330-mm reel packing (If no packing code is indicated, this corresponds to 40) Example 1: Example 2: B57164K0102J000 B57164K0102J052 B57881S0103F002 B57881S0103F251 Bulk Cardboard tape, cassette packing Bulk Cardboard tape, reel packing Please read Cautions and warnings and Important notes at the end of this document. Page 15 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Mounting instructions 1 1.1 Soldering Leaded NTC thermistors Leaded thermistors comply with the solderability requirements specified by CECC. When soldering, care must be taken that the NTC thermistors are not damaged by excessive heat. The following maximum temperatures, maximum time spans and minimum distances have to be observed: Dip soldering Bath temperature Soldering time Distance from thermistor max. 260 °C max. 4 s min. 6 mm Iron soldering max. 360 °C max. 2 s min. 6 mm Under more severe soldering conditions the resistance may change. 1.2 Leadless NTC thermistors In case of NTC thermistors without leads, soldering is restricted to devices which are provided with a solderable metallization. The temperature shock caused by the application of hot solder may produce fine cracks in the ceramic, resulting in changes in resistance. To prevent leaching of the metallization, solder with silver additives or with a low tin content should be used. In addition, soldering methods should be employed which permit short soldering times. 2 Clamp contacting Pressure contacting by means of clamps is particularly suitable for applications involving frequent switching and high turn-on powers. 3 Robustness of terminations (leaded types) The leads meet the requirements of IEC 60068-2-21. They may not be bent closer than 4 mm from the solder joint on the thermistor body or from the point at which they leave the feedthroughs. During bending, any mechanical stress at the outlet of the leads must be removed. The bending radius should be at least 0.75 mm. Tensile strength: Test Ua1: Leads 0.25 < 0.35 < 0.50 < 0.80 < ∅ ≤0.25 mm = 1.0 N ∅ ≤0.35 mm = 2.5 N ∅ ≤0.50 mm = 5.0 N ∅ ≤0.80 mm = 10.0 N ∅ ≤1.25 mm = 20.0 N Please read Cautions and warnings and Important notes at the end of this document. Page 16 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 Bending strength: Test Ub: Two 90°-bends in opposite directions at a weight of 0.25 kg. Torsional strength: Test Uc: severity 2 The lead is bent by 90° at a distance of 6 to 6.5 mm from the thermistor body. The bending radius of the leads should be approx. 0.75 mm. Two torsions of 180° each (severity 2). When subjecting leads to mechanical stress, the following should be observed: Tensile stress on leads During mounting and operation tensile forces on the leads are to be avoided. Bending of leads Bending of the leads directly on the thermistor body is not permissible. A lead may be bent at a minimum distance of twice the wire's diameter +2 mm from the solder joint on the thermistor body. During bending the wire must be mechanically relieved at its outlet. The bending radius should be at least 0.75 mm. Twisting of leads The twisting (torsion) by 180° of a lead bent by 90° is permissible at 6 mm from the bottom of the thermistor body. 4 Sealing and potting When thermistors are sealed, potted or overmolded, there must be no mechanical stress caused by thermal expansion during the production process (curing / overmolding process) and during later operation. The upper category temperature of the thermistor must not be exceeded. Ensure that the materials used (sealing / potting compound and plastic material) are chemically neutral. 5 Cleaning If cleaning is necessary, mild cleaning agents such as ethyl alcohol and cleaning gasoline are recommended. Cleaning agents based on water are not allowed. Ultrasonic cleaning methods are permissible. 6 Storage In order to maintain their solderability, thermistors must be stored in a non-corrosive atmosphere. Humidity, temperature and container materials are critical factors. Do not store SMDs where they are exposed to heat or direct sunlight. Otherwise, the packing material may be deformed or SMDs may stick together, causing problems during mounting. After opening the factory seals, such as polyvinyl-sealed packages, use the SMDs as soon as possible. Please read Cautions and warnings and Important notes at the end of this document. Page 17 of 23 Temperature measurement and compensation Leaded NTC thermistors, lead spacing 2.5 mm B57891M M891 The components should be left in the original packing. Touching the metallization of unsoldered thermistors may change their soldering properties. Storage temperature: Relative humidity (without condensation): 25 °C up to 45 °C ≤75% annual mean