橡膠電阻率測試儀 本儀器既可測量高電阻，又可測微電流。采用了美國Intel公司的大規(guī)模集成電路,使儀器體積小、重量輕、準(zhǔn)確度高。

電阻率測試儀是電阻率監(jiān)視儀，電阻率和溫度同時顯示，并具有電阻率低限報警功能的在線面板式儀表，廣泛應(yīng)用于制藥、電子、化工等行業(yè)對工業(yè)流程水質(zhì)的在線監(jiān)測。它采用了單片機技術(shù)，對純水的溫度系數(shù)、電極常數(shù)及電阻率低限報警點通過面板上的按鍵自由設(shè)置，是各種中小型純水設(shè)備的理想配套儀表。

橡膠電阻率測試儀  技術(shù)指標(biāo)
1、電阻測量范圍： 0.01×104Ω ～1×1018Ω。
2、電流測量范圍： 2×10-4A～1×10-16A
3、顯 示 方 式：液晶、電阻、電流雙顯示
4、內(nèi)置測試電壓： 10V 、50V、100V、250V、500V、1000V（任意切換）；
5、基本準(zhǔn)確度：≤1%；
6、使用環(huán)境：溫度：0℃～40℃，相對濕度<80%
7、供電形式：AC 220V，50HZ，功耗約5W
8、全自動測量、體積小、重量輕、準(zhǔn)確度高，電阻、電流雙顯示，性能好穩(wěn)定、讀數(shù)方便
9、所有測試電壓(10V/50V/100/250/500/1000V) 測試時電阻結(jié)果直讀
10、配置：
主機：一臺
屏蔽箱+電極：一套
測試線：五條
說明書+合格證+保修卡：各一份
備注：
    本儀器配不同的測量電極（夾具）可以測量不同材料（固體、粉體或液體）的體積電阻率和表面電阻率或電導(dǎo)率，*符合國家標(biāo)準(zhǔn)GB1410－2006固體電工絕緣材料絕緣電阻、體積電阻系數(shù)和表面電阻試驗方法，ASTM D257 絕緣材料的直流電阻或電導(dǎo)試驗方法等標(biāo)準(zhǔn)要求。

橡膠電阻率測試儀  主要特點
電阻測量范圍寬  1×104Ω～1×1018Ω
電流測量范圍為 2×10-4Ａ～1×10-16Ａ
體積小、重量輕、準(zhǔn)確度高
電阻、電流雙顯示
性能好穩(wěn)定、讀數(shù)方便
所有測試電壓(100/250/500/1000V) 測試時電阻結(jié)果直讀，免去老式高阻計在不同測試電壓下或不同量程時要乘以系數(shù)等使用不便的麻煩，使測量超高電阻就如用萬用表測量普通電阻樣簡便。既能測超高電阻又能測微電流

測試項目：體積電阻、表面電阻、體積電阻率、表面電阻率、絕緣電阻、電阻率、微電流等

工作原理
根據(jù)歐姆定律，被測電阻Rx等于施加電壓V除以通過的電流I。傳統(tǒng)的高阻計的工作原理是測量電壓V固定，通過測量流過取樣電阻的電流I來得到電阻值。從歐姆定律可以看出，由于電流I是與電阻成反比，而不是成正比，所以電阻的顯示值是非線性的，即電阻無窮大時，電流為零，即表頭的零位處是∞，其附近的刻度非常密，分辨率很低。整個刻度是非線性的。又由于測量不同的電阻時，其電壓V也會有些變化，所以普通的高阻計是精度差、分辨率低。
本儀器是同時測出電阻兩端的電壓V和流過電阻的電流I，通過內(nèi)部的大規(guī)模集成電路完成電壓除以電流的計算，然后把所得到的結(jié)果經(jīng)過A/D轉(zhuǎn)換后以數(shù)字顯示出電阻值，即便是電阻兩端的電壓V和流過電阻的電流I是同時變化，其顯示的電阻值不象普通高阻計那樣因被測電壓V的變化或電流Ｉ的變化而變，所以，即使測量電壓、被測量電阻、電源電壓等發(fā)生變化對其結(jié)果影響不大，其測量精度很高，從理論上講其誤差可以做到零，而實際誤差可以做到千分之幾或萬分之幾。
Working principle
According to Ohm's law, the measured resistance Rx is equal to the applied voltage V divided by the current I through which it passes. The working principle of traditional high resistance meter is to measure the voltage V fixed, and get the resistance value by measuring the current I flowing through the sampled resistance. Ohm's law shows that because current I is inversely proportional to resistance, rather than directly proportional to it, the display value of resistance is non-linear, that is, when resistance is infinite, the current is zero, that is to say, the zero position of the head is infinity, the scale near it is very close and the resolution is very low. The whole scale is non-linear. Because the voltage V will change when measuring different resistors, the common high resistors have poor accuracy and low resolution.
This instrument measures the voltage V at both ends of the resistance and the current I passing through the resistance at the same time, completes the calculation of voltage divided by current through the internal large scale integrated circuit, and then displays the resistance value digitally after A/D conversion, even if the voltage V at both ends of the resistance and the current I passing through the resistance change simultaneously. The resistance value displayed is not changed by the change of voltage V or current I, as is the case with ordinary high resistance meters. Therefore, even if the change of measurement voltage, resistance and power supply voltage has little effect on the result, the measurement accuracy is very high (patent). In theory, the error can be zero, while the actual error can be zero. Make it a few thousandths or a few thousandths.

電阻率的計算公式為：
   PL
R= —
   S

ρ為電阻率——常用單位Ω·mm2/m
S為橫截面積——常用單位㎡
R為電阻值——常用單位Ω
L為導(dǎo)線的長度——常用單位m