产品工程师 发布的文章

需要准备的工具和附件如下:
1、普通中等大小十字螺丝刀
2、标准的C45/DIN35导轨和固定导轨用的配套螺丝
3、PF083A底座
4、若干电源线

安装步骤:
第一步:根据安装位置截取适合长度的导轨,本产品需要大于8cm长度的导轨,使用螺丝固定导轨在相应的位置
第二步:把PF083A标准底座卡好在导轨的相应位置
第三步:根据接线图接好线,检查接线是否错误
第四步:插入温度控制器,调节旋钮设置相应的控制温度
第五步:上电运行

atc_sam.jpg

ATC可调温度控制器在设计初期就针对市场上的产品进行优化改善,支持外接或内置的高精度双NTC温度传感器,使温度控制更灵活可靠。在内外温度传感器上有“外置优先”和“仅限外置”两个不同的版本供选择,外置优先为:当接入外置温度传感器时采用外置温度探头进行控制,当外置温度探头拔出时自动切换到内置温度传感器进行控制;仅限外置为:禁用内置温度传感器,当外置温度传感器拔出时,控制器处理停止工作的状态,直至再次插入传感器为止才能继续工作。当控制器识别到温度探头时NTC指示灯点亮。本产品采用工业级Atmel微处理器,传感器精度±0.3℃,在25℃区间可达到医用级别要求。

一、热敏电阻公式

NTC 热敏电阻温度计算公式:Rt = R EXP(B(1/T1-1/T2))

其中,T1和T2指的是K度,即开尔文温度。

Rt 是热敏电阻在T1温度下的阻值。

R是热敏电阻在T2常温下的标称阻值。100K的热敏电阻25℃的值为100K(即R=100K)。T2=(273.15+25)

EXP是e的n次方

B值是热敏电阻的重要参数

通过转换可以得到温度T1与电阻Rt的关系T1=1/(ln(Rt/R)/B+1/T2)

对应的摄氏温度t=T1-273.15,同时+0.5的误差矫正。

二、硬件连接

单片机是3.3V供电,热敏电阻与100K电阻连接。

热敏电阻参数为100K,B值为3950

三、程序

下面是程序(stm32),检测了4路温度

因为要用到数学函数所以需要添加头文件#include "math.h"

然后写公式(电压转换、电阻转换、温度转换)

四、ln、log、lg说明

数学中的公式和c语言中有小小的区别。

1、数学中

log是对数符号,右边写真数和底数(上面是真数,下面是底数)

lg是以10为底数(例lg100=2)(lg为常用对数)

ln是以e为底数(lne2=2)(ln为自然对数 e=2.7182818284590452353602874713527...)

2、c语言中

c语言里面只有两个函数log和log10

其中

函数 log(x) 表示是以e为底的自然对数,即 ln(x)

函数 log10(x) 以10为底的对数,即 lg(x)

以其它数为底的对数用换底公式来表示

函数如下:

double logab(double a,double b)
{
return log(b)/log(a);
}

https://blog.csdn.net/yangyang_1024/article/details/80563522

NTC热敏电阻的阻值与温度对照表主要关注几个方面:温度、NTC阻值、阻值公差及B值。

NTC热敏电阻随着温度的升高而降低了电阻,并提供各种基本电阻和曲线。我们通知情况所说的阻值即为NTC的的标称阻值,大多数情况下即25℃时的阻值,它提供了一个方便的参考点。例如,10K的NTC热敏电阻即它在25℃时的阻值为10KΩ,当然有也有些特殊的阻值是以其它温度为标称的,参见RT表说明。

另一个重要特征是“B”值。B值是材料常数,其由制成它的陶瓷材料确定,并描述在两个温度点之间的特定温度范围内的电阻(R/T)曲线的梯度。每个热敏电阻材料将具有不同的材料常数,因此具有不同的电阻与温度曲线。然后,B值将定义第一温度或基点(通常为25℃)的热敏电阻电阻值(称为T1),以及第二温度点(例如50℃,称为T2 )的热敏电阻电阻值。因此,B值将使热敏电阻材料在T1和T2的范围内保持恒定。即B:T1/T2或B:25/85,典型的NTC热敏电阻B值在约3000和约5000之间。

本R/T表(阻值/温度)对照表数据:
1、阻值:本表标称阻值在25℃时为:100KΩ
2、阻值公差:本表的阻值允许公差为:±1%
3、B值:本表的B值在25/50℃时为:3950K

TEMPERATURE VS RESISTANCE TABLE
Resistance 100k Ohms at 25deg. C
Resistance Tolerance + / -1%
B Value 3950K at 25/50deg. C
B Value Tolerance + / - 1%

温度 (℃)最大值 (KΩ)标准值 (KΩ)最小值 (KΩ)
-301858.69271787.97971719.7849
-291744.9371679.60171616.551
-281638.89121578.50611520.194
-271539.98471484.15841430.2129
-261447.69291396.06621346.1459
-251361.53151313.77541267.5675
-241281.0561236.86851194.0856
-231205.85611164.95981125.3381
-221135.55321097.69411060.9911
-211069.79921034.74321000.7358
-201008.2715975.8038944.2871
-19950.6732920.5962891.3817
-18896.7294868.8615841.7754
-17846.1864820.3603795.2428
-16798.8093774.871751.575
-15754.381732.1889710.5786
-14712.7005692.1238672.0741
-13673.5814654.4999635.8954
-12636.8513619.154601.8883
-11602.3502585.9346569.9095
-10569.9298554.7016539.8262
-9539.4526525.3245511.5153
-8510.7906497.6821484.8615
-7483.8254471.6621459.7586
-6458.4467447.1599436.1073
-5434.5519424.0781413.8153
-4412.046402.3264392.7968
-3390.8401381.8204372.9716
-2370.8519362.4818354.2653
-1352.0045344.2375336.6083
0334.2264327.0195319.936
1317.4508310.764304.1877
2301.6157295.4121289.3072
3286.6631280.9084275.2418
4272.5389267.2014261.9423
5259.1926254.2428249.3626
6246.577241.9877237.4601
7234.6482230.394226.1943
8223.365219.4224215.5278
9212.689209.0361205.4255
10202.584199.2007195.8544
11193.0167189.8841186.7836
12183.9552181.0559178.1844
13175.3704172.6881170.0298
14167.2345164.754162.2942
15159.5216157.229154.9539
16152.2075150.0898147.9867
17145.2694143.3144141.3716
18138.6861136.8825135.0889
19132.4375130.7749129.1202
20126.5049124.9734123.4482
21120.8705119.4612118.0564
22115.518114.2223112.9298
23110.4316109.2417108.0537
24105.5969104.5053103.4147
2510110099
2696.712795.713294.7146
2792.630691.633390.6378
2888.742687.749286.7583
2985.038684.050583.0655
3081.50980.527479.5497
3178.144677.170776.2012
3274.93773.971773.0115
3371.877970.922269.9721
3468.959868.014467.0752
3566.175565.241164.3134
3663.518262.595461.6798
3760.981460.070759.1677
3858.559157.66156.771
3956.245655.360454.4837
4054.035553.163552.3004
4151.923551.065150.2158
4249.904949.060248.225
4347.975247.144346.3232
4446.129845.31344.5062
4544.364943.562142.7696
4642.676441.887841.1096
4741.060740.286239.5224
4839.514338.753938.0044
4938.033937.287636.5524
5036.616335.884235.1631
5135.258734.540533.8335
5233.958233.253832.5608
5332.712132.021431.3423
5431.517830.840830.1754
5530.373129.709629.0576
5629.275528.625327.9868
5728.22327.58626.9607
5827.213526.589525.9772
5926.24525.633825.0343
6025.315624.717124.1303
6124.423723.837623.2633
6223.567522.993722.4315
6322.745422.183621.6336
6421.95621.406120.8678
6521.197720.659420.1328
6620.469219.942419.4272
6719.769319.253718.7497
6819.096618.59218.099
6918.449917.956217.474
7017.828217.345216.8735
7117.230416.757816.2965
7216.655416.19315.7419
7316.102315.649915.2087
7415.570215.127614.6961
7515.058114.625114.2032
7614.565214.141713.7291
7714.090713.676413.2729
7813.633913.228612.8341
7913.19412.797612.4118
8012.770312.382512.0053
8112.362211.982811.6139
8211.968911.597811.2372
8311.5911.22710.8743
8411.224710.869710.5248
8510.872710.525410.1881
8610.533210.19359.8637
8710.20599.87369.5511
889.89029.56529.2499
899.58589.26788.9594
909.2928.98098.6794
919.00858.70428.4094
928.7358.43738.1489
938.4718.17977.8977
948.21617.93127.6554
957.977.69127.4215
967.73247.45967.1958
977.50297.2366.978
987.28127.02016.7677
997.0676.81156.5647
1006.86016.61016.3686
1016.66016.41556.1793
1026.46686.22745.9964
1036.27996.04575.8197
1046.09935.87015.6489
1055.92465.70035.4839
1065.75575.53625.3245
1075.59235.37755.1703
1085.43435.2245.0213
1095.28145.07554.8772
1105.13344.93194.7379
1114.99034.7934.6031
1124.85174.65864.4727
1134.71754.52854.3466
1144.58774.40264.2245
1154.46194.28074.1064
1164.34014.16273.9921
1174.22224.04843.8815
1184.10793.93783.7743
1193.99723.83063.6706
1203.893.72683.5702
1213.78613.62633.4729
1223.68543.52893.3787
1233.58773.43453.2874
1243.49313.3433.199
1253.40143.25433.1133
1263.31243.16833.0302
1273.22613.0852.9497
1283.14243.00422.8717
1293.06132.92582.796
1302.98252.84982.7227
1312.90612.77612.6515
1322.8322.70452.5826
1332.76012.63522.5157
1342.69022.56782.4507
1352.62252.50252.3878
1362.55672.43912.3267
1372.49282.37752.2674
1382.43082.31782.2098
1392.37052.25982.154
1402.3122.20342.0997
1412.25522.14872.0471
1422.22.09561.996
1432.14632.0441.9463
1442.09421.99391.8981
1452.04361.94521.8513
1461.99431.89781.8058
1471.94651.85181.7616
1481.91.80711.7187
1491.85471.76371.677
1501.81081.72151.6364
1511.7681.68041.597
1521.72641.64051.5587
1531.6861.60171.5215
1541.64671.5641.4853
1551.60841.52731.4501
1561.57121.49151.4158
1571.53491.45681.3825
1581.49971.4231.3501
1591.46541.39011.3186
1601.4321.35821.288
1611.39951.3271.2582
1621.36781.29671.2292
1631.3371.26721.2009
1641.3071.23851.1734
1651.27781.21061.1467
1661.24941.18331.1207
1671.22171.15681.0953
1681.19471.1311.0706
1691.16841.10591.0466
1701.14281.08141.0232
1711.11791.05761.0004
1721.09351.03430.9782
1731.06981.01170.9566
1741.04670.98960.9355
1751.02420.96810.915
1761.00230.94720.895
1770.98090.92680.8756
1780.96010.90690.8566
1790.93970.88750.8381
1800.91990.86860.82
1810.90060.85010.8024
1820.88170.83210.7853
1830.86330.81460.7686
1840.84540.79750.7523
1850.82790.78080.7364
1860.81080.76460.7209
1870.79410.74870.7058
1880.77790.73320.6911
1890.7620.71810.6767
1900.74650.70340.6627
1910.73140.6890.649
1920.71660.67490.6356
1930.70220.66120.6226
1940.68820.64790.6099
1950.67440.63480.5975
1960.6610.62210.5853
1970.64790.60960.5735
1980.63510.59750.562
1990.62270.58560.5507
2000.61050.5740.5397
2010.59850.56270.529
2020.58690.55170.5185
2030.57550.54090.5082
2040.56440.53030.4982
2050.55360.520.4884
2060.5430.50990.4789
2070.53260.50010.4696
2080.52250.49050.4604
2090.51260.48110.4515
2100.50290.47190.4428
2110.49340.4630.4343
2120.48420.45420.426
2130.47510.44560.4179
2140.46630.43720.41
2150.45760.4290.4022
2160.44920.4210.3946
2170.44090.41320.3872
2180.43280.40550.38
2190.42490.3980.3729
2200.41710.39070.366
2210.40960.38360.3592
2220.40210.37650.3525
2230.39490.36970.3461
2240.38780.3630.3397
2250.38090.35640.3335
2260.37410.350.3274
2270.36740.34370.3215
2280.36090.33760.3157
2290.35450.33150.31
2300.34830.32570.3045
2310.34220.31990.299
2320.33620.31420.2937
2330.33040.30870.2885
2340.32460.30330.2834
2350.3190.2980.2784
2360.31350.29280.2735
2370.30810.28780.2687
2380.30290.28280.264
2390.29770.27790.2594
2400.29270.27320.2549
2410.28770.26850.2505
2420.28290.26390.2462
2430.27810.25940.242
2440.27340.2550.2379
2450.26890.25070.2338
2460.26440.24650.2298
2470.260.24240.2259
2480.25570.23840.2221
2490.25150.23440.2184
2500.24740.23050.2148
2510.24330.22670.2112
2520.23940.2230.2077
2530.23550.21930.2042
2540.23170.21570.2009
2550.22790.21220.1976
2560.22430.20880.1943
2570.22070.20540.1911
2580.21720.20210.188
2590.21370.19880.185
2600.21030.19570.182
2610.2070.19250.1791
2620.20370.18950.1762
2630.20050.18650.1734
2640.19740.18350.1706
2650.19430.18060.1679
2660.19130.17780.1652
2670.18840.1750.1626
2680.18550.17230.1601
2690.18260.16960.1575
2700.17980.1670.1551
2710.17710.16440.1527
2720.17440.16190.1503
2730.17170.15940.148
2740.16910.1570.1457
2750.16660.15460.1435
2760.16410.15220.1413
2770.16160.14990.1391
2780.15920.14770.137
2790.15680.14550.1349
2800.15450.14330.1329
2810.15220.14120.1309
2820.150.13910.1289
2830.14780.1370.127
2840.14560.1350.1251
2850.14350.1330.1232
2860.14140.1310.1214
2870.13940.12910.1196
2880.13740.12720.1179
2890.13540.12540.1161
2900.13350.12360.1144
2910.13160.12180.1128
2920.12970.12010.1111
2930.12790.11830.1095
2940.1260.11660.1079
2950.12430.1150.1064
2960.12250.11340.1049
2970.12080.11180.1034
2980.11910.11020.1019
2990.11750.10860.1005
3000.11580.10710.099

负温度系数热敏电阻,简称为NTC热敏电阻,它的阻值随着工作温度的增加而降低。目前,因为NTC热敏电阻的几乎可以应用于对温度起作用的任何类型的设置中及它的高性价比,所以NTC热敏电阻已经成为最常用的温度传感器类型。

在采用NTC热敏电阻之前,得先搞明白NTC热敏电阻特有的阻值与温度(R/T)之间的关系。NTC热敏电阻的相对较大的负系数响应意味着即使很小的温度变化也会导致其电阻发生明显的变化,这也是NTC成为精确温度测试和控制的重要原因。

NTC热敏电阻特性曲线
1-1Z21Q6344XG.gif
此图就是典型的负温度系数(NTC)曲线,其电阻随温度升高而降低。