耐電壓擊穿場強(qiáng)電氣強(qiáng)度試驗(yàn)儀電壓擊穿試驗(yàn)儀
使電介質(zhì)擊穿的電壓。電介質(zhì)在足夠強(qiáng)的電場作用下將失去其介電性能成為導(dǎo)體,稱為電介質(zhì)擊穿,所對應(yīng)的電壓稱為擊穿電壓。
電介質(zhì)擊穿時的電場強(qiáng)度叫擊穿場強(qiáng)。不同電介質(zhì)在相同溫度下,其擊穿場強(qiáng)不同。當(dāng)電容器介質(zhì)和兩極板的距離d一定后,由U1-U2=Ed知,擊穿場強(qiáng)決定了擊穿電壓。擊穿場強(qiáng)通常又稱為電介質(zhì)的介電強(qiáng)度。
提高電容器的耐壓能力起關(guān)鍵作用的是電介質(zhì)的介電強(qiáng)度。附表為各種電介質(zhì)的相對介電常量εr和介電強(qiáng)度。電介質(zhì)εr擊穿場強(qiáng),×106/(V·m-1)
耐電壓擊穿場強(qiáng)電氣強(qiáng)度試驗(yàn)儀正確選用耐壓測試儀
選用耐壓儀zui重要的是2個指標(biāo),zui大輸出電壓值及zui大報警電流值一定要大于你所需要的電壓值和報警電流值。
一般被試產(chǎn)品標(biāo)準(zhǔn)中規(guī)定了施加高壓值及報警判定電流值。如果施加的電壓越高,報警判定電流越大,那么需要耐壓儀升壓變壓器功率就越大,一般耐壓儀升壓變壓器功率有0.2kVA、0.5kVA、1kVA、2kVA、3kVA等。zui高電壓可以到幾萬伏。zui大報警電流500mA-1000mA等。所以在選擇耐壓儀時一定要注意這2個指標(biāo)。
功率選太大就會造成浪費(fèi),選的太小耐壓試驗(yàn)不能正確判斷合格與否。
根據(jù)IEC414或(GB6738-86)中規(guī)定選擇耐壓儀的功率方法,我們認(rèn)為是比較科學(xué)的。“首先將耐壓儀的輸出電壓調(diào)到規(guī)定值的50%,然后接上被試品,當(dāng)觀測到的電壓降小于該電壓值的10%時,則認(rèn)為耐壓儀的功率是足夠的。”
也就是如果某一產(chǎn)品的耐壓試驗(yàn)的電壓值為3000伏,先把耐壓儀的輸出電壓調(diào)到1500伏后接上被試品,如果此時耐壓儀輸出電壓下降的值不大于150伏,那么耐壓儀的功率是足夠的。被試品的帶電部分與外殼之間存在分布電容。電容存在一個CX容抗,當(dāng)一個交流電壓施加在這CX電容兩端就會引成一個電流。
這個電流的大小與CX電容的容量成正比與施加的電壓值成正比,當(dāng)這個電流大到或超過耐壓儀zui大輸出電流時,這臺耐壓儀就不能正確判別試驗(yàn)合格與否。
電纜耐電壓的試驗(yàn)方法
1、應(yīng)采用成品電線的試樣按28.2—28.9所述的方法做試驗(yàn)。應(yīng)試驗(yàn)絕緣線、絕緣扁電纜或護(hù)套電纜的絕緣線芯。在護(hù)套電纜的情況下,應(yīng)取出絕緣線芯并獨(dú)立于護(hù)套電纜做試驗(yàn)。
2、對于每個需進(jìn)行評價的電線樣品,應(yīng)取6個絕緣線或護(hù)套電纜的絕緣線芯試樣做試驗(yàn)。每個試樣應(yīng)長24in(610mm)。其中3個試樣在未老化狀態(tài)下做試驗(yàn),另3個試樣應(yīng)經(jīng)過烘箱處理后做試驗(yàn)。
3、三個用于烘箱處理的直線狀試樣應(yīng)放進(jìn)烘箱中進(jìn)行處理,處理時間和烘箱溫度應(yīng)與本標(biāo)準(zhǔn)第14節(jié):絕緣和護(hù)套末老化和烘箱老化后物理性能所述和試驗(yàn)*。
4、烘箱處理以后,應(yīng)將這3個試樣放在室溫的靜止空氣中泠卻16-96小時然后做試驗(yàn)。泠卻期結(jié)束以后,同時采用末老化和烘箱老化的試樣做試驗(yàn)。采用金屬箔包每個試樣*的12in(305mm)的部分。
5、除了扁電線外,應(yīng)將每個試樣的金屬箔繞包部分繞在金屬試棒上6個完整的緊密相連的圈。試棒直徑應(yīng)為試樣外徑的2倍或是0.19in(5mm)取二者中較大者,每個由此形成地螺旋線的端頭應(yīng)松松地纏繞在一起或是采用粘接帶固定在一起以防止退繞。扁電線試樣應(yīng)圍繞直徑等于短徑2倍的試棒彎曲成U形并與試棒接觸至少180°。
6、介電試驗(yàn)機(jī)應(yīng)能提供50或是60HZ連續(xù)可變從零至電線試樣額定電壓5倍的輸出電壓。電路中接上試樣后,輸出電壓的峰值因數(shù)(峰值除以均方根值)應(yīng)等于純正波上半部輸出范圍峰值因數(shù)的95-105%。應(yīng)使用電壓表連續(xù)臨測輸出電壓,該電壓表的響應(yīng)時間在規(guī)定的升壓速度下不會造成大于1%滿盤的滯后的誤差。其總電壓精度不會造成大于5%的誤差。試驗(yàn)機(jī)變壓器可輸出的zui大電流應(yīng)保證可進(jìn)行試樣的擊穿試驗(yàn)而示發(fā)持加載電流引起斷路器跳閘現(xiàn)象。
7、將介電試驗(yàn)機(jī)的一根試驗(yàn)引接到作為一個電極的試樣的導(dǎo)體上,并另一根試驗(yàn)引接到作為另一個電極的金屬試棒上,電壓應(yīng)從零開始上升至28.1
規(guī)定的試驗(yàn)電壓。升壓速度不得超過500V/s如果達(dá)到水平無擊穿,電壓應(yīng)保持在該水平60秒。
8、試驗(yàn)電壓在規(guī)定電壓水平上維持60秒后,應(yīng)以不超過500V/S的速度繼續(xù)升壓至擊穿。應(yīng)分別記錄末老化試樣和烘箱老化試樣的介質(zhì)擊穿電壓并分別求出末老化試樣和烘箱的老化試樣的介質(zhì)擊穿電壓的平均值。
9、末老化試樣和烘箱老化試樣應(yīng)滿足下列要求:
a)末老化試樣和烘箱老化試樣應(yīng)耐受28.1規(guī)定的試驗(yàn)電壓60秒不擊穿;
b) 烘箱梅化試樣的介質(zhì)擊穿電壓的平均值不得小于末老化試樣平均值的50%。
配置及其技術(shù)參數(shù)
1 試驗(yàn)變壓器
1.1 輸出電壓: AC 0-10000V,DC 0-10000V;
1.2 輸入電壓:220v
1.3 額定容量下,*連續(xù)運(yùn)行;
1.4 zui大輸出電壓下,PD≤1pC;
1.5 噪聲≤58dB(1m位置測量)。
2 調(diào)壓器
2.1 輸入電壓:220V;
2.2 額定容量:2kVA(如果有補(bǔ)償,可以小于15kVA,但不小于10kVA);
2.3額定容量下,*連續(xù)運(yùn)行;
2.4噪聲≤58dB(1m位置測量);
2.5 電動調(diào)壓。
3 高壓分壓器
3.1 高壓臂電容:1nF;
3.2 分壓比:700(可討論,結(jié)合測量控制系統(tǒng));
3.3 額定容量下,*連續(xù)運(yùn)行;
3.4 zui大輸出電壓下,PD≤1pC;
3.5 測量精度:1%。
4 計算機(jī)控制
4.1 藍(lán)牙連接;
4.2 安全保護(hù);
技術(shù)指標(biāo):
輸入電壓: 交流 220 V 輸出電壓: 交流 0--100 KV ;/直流 0—100 KV
電器容量: 10KVA 高壓分級: 0-100KV 升壓速率:0.01-5.0kv
(備注:滿足標(biāo)準(zhǔn)要求并可以根據(jù)用戶需求設(shè)定不同的升壓速率)
06、試驗(yàn)方式: 交流試驗(yàn)/ 直流試驗(yàn):1、勻速升壓 2、梯度升壓 3、耐壓試驗(yàn)
試驗(yàn)介質(zhì):空氣,試驗(yàn)油 安裝靈敏度較高的過電流保護(hù)裝置保證試樣擊穿時在0.05S內(nèi)切斷電源。 儀器配備*的故障報警系統(tǒng) 避免用戶操作故障儀器發(fā)生危險。(上位機(jī)報警和下位機(jī)報警)
組成:
1、升壓部件:由調(diào)壓器和高壓變壓器組成0~50KV的升壓部分。
2、動部件:由步進(jìn)電機(jī)均勻調(diào)節(jié)調(diào)壓器使加給高壓變壓器的電壓變化。
3、檢測部件:由集成電路組成的測量電路。通過信號線把檢測的模擬信號和開關(guān)信號傳給計算機(jī)。
4、計算機(jī)軟件:通過智能電路把由檢測設(shè)備采集的測控信號傳給計算機(jī)。計算機(jī)根據(jù)采集的信息控制設(shè)備運(yùn)行并處理試驗(yàn)結(jié)果。
5、試驗(yàn)電極:根據(jù)標(biāo)準(zhǔn)(1408.1-2006)隨設(shè)備提供三個電*體規(guī)格為:Ф25mm×25mm兩個;Ф75mm×25mm一個。(訂做除外)
Breakdown voltage breakdown voltage electric strength test instrument pressure resistance tester
The dielectric breakdown voltage. Dielectric under the action of electric field in a strong enough will lose its dielectric properties become the conductor, called the dielectric breakdown, the corresponding voltage is called the breakdown voltage.
When the dielectric breakdown electric field intensity is called breakdown voltage. Different dielectric under the same temperature, the breakdown voltage is different. Capacitor medium and the plates, after a certain distance d by U1 - U2 = Ed, breakdown voltage determines the breakdown voltage. Dielectric breakdown voltage is often called the dielectric.
Increase the ability of condenser pressure is dielectric plays the key role of dielectric strength. Schedule for all kinds of dielectric epsilon r relative dielectric constants and dielectric strength. Dielectric breakdown field strength epsilon r, x 106 / (v. m - 1)
Voltage breakdown voltage electric resistance strength tester correctly choose hipot tester
Selection of pressure gauge is the most important two indicators, alarm of the maximum output voltage and current value must be greater than you need voltage values and alarm current value.
General subjects specified in the product standard under pressure values and alarm judge current value. If the applied voltage is high, report to the police to determine the current, the greater the pressure meter is necessary step-up transformer the greater the power, the general pressure gauge step-up transformer power 0.2 kVA, 0.5 kVA, 1 kVA, 2 kVA, 3 kVA, etc. The highest voltage can be for tens of thousands of volts. The largest alarm current 500 ma - 1000 ma, etc. So when choosing pressure gauge must pay attention to these two indicators.
The power to choose too much can cause waste, correct judgment is too small pressure test is qualified or not.
According to IEC414 or (GB6738-86) specified in the selection pressure instrument power method, we think that is more scientific. \"First of all the pressure gauge, and 50% of the output voltage is transferred to the specified value and then connected to the participants to taste, when the observed voltage drop less than 10% of the voltage value, think the power of pressure gauge is enough.\"
, that is, if a product of the pressure test voltage is 3000 v, the pressure gauge first after the output voltage to 1500 volts of connected to the participants to taste, if the pressure gauge output voltage drop value is not greater than 150 v, so the power of pressure gauge is enough. The sample (s) is distributed capacitance between shell and the live part. Capacitor CX capacitive reactance, there is a when a voltage applied on both ends of the CX capacitance will lead into an electric current.
The size of the current is proportional to the CX capacitance capacity is proportional to the applied voltage, when the current is too big to or exceed the pressure meter maximum output current, the pressure gauge can't correct discrimination test or not.
Cable withstand voltage test method
1, the sample of the finished wire should be adopted in the way described in 28.2-28.9 do an experiment. Should be insulated wire, flat cable insulation or sheath cable insulation wire core. Under the condition of the sheathed cable, should remove insulation wire core and is independent of the sheathed cable to do an experiment.
2, for each of the need to evaluate wire samples, should take six insulation or sheath cable insulation wire core sample test. 24 in each sample should be long (610 mm). Three samples without aging experiment condition, the other three sample should do after dealing with the oven test.
3, three straight line shape sample should be used to deal with the oven into oven for processing, processing time and drying oven temperature should be with section 14 of this standard: at the end of the insulation and sheath after the aging and oven ageing properties described and experiment are consistent.
4, oven after processing, should put the three samples at room temperature in still air ling but 16-96 hours and then do an experiment. At the end of the ling but after the period, at the same time, the aging and oven ageing test specimens. Using metal foil bag each 12 in the middle of the sample (305 mm).
5, in addition to the flat wire, each sample should be around the metal foil winding and part of the test bar on six full circle are closely linked. Sample test bar diameter should be 2 times of overall diameter or 0.19 (5 mm) in both in highly actie, each resulting in the end of the helix YingSongSong ground together or use adhesive tape of fixed together to prevent unwinding. Flat wire samples should be 2 times around the diameter is equal to the short diameter of test bar bent into U and contact with the test bar at least 180 °.
Six, dielectric tester should be able to provide 50 or 60 hz continuous variable from zero to wire the sample 5 times rated voltage output voltage. Circuit connected to the sample, after the peak factor of the output voltage divided by the root mean square (peak value) should be equal to the upper pure wave output range 95-105% of the peak factor. Voltmeter should be used in the continuous measurement of the output voltage, the response time of the voltmeter will not result in greater than 1% under the specified speed booster plateful of lag error. The total voltage accuracy will not result in more than 5% of error. Testing machine output the maximum current of transformer should be guarantee for the breakdown of the sample test and send the load current circuit breaker tripping caused phenomenon.
7, will be a test of dielectric tester received as an electrode on the conductor of the specimen, and the other test lead received as another electrode metal test bar, voltage should be starting from scratch up to 28.1
The prescribed test voltage. Booster speed should not exceed 500 v/s if level and no breakdown, voltage should be kept in the level of 60 seconds.
8, test voltage to maintain the prescribed voltage level after 60 seconds, should be no more than 500 v/S continue to step up to the speed of the breakdown. Should record the aging samples and oven ageing samples at the end of the dielectric breakdown voltage and calculated respectively at the end of the aging of the specimen and oven ageing dielectric breakdown voltage of the average.
At the end of September and aging samples and oven ageing samples shall meet the following requirements:
A) 28.1 aging samples and oven ageing samples should be at the end of the tolerance specified test voltage breakdown in 60 seconds;
B) oven of mei sample average dielectric breakdown voltage shall not be less than 50% of aging at the end of the sample average.
Withstand voltage breakdown voltage electric strength test device configuration and technical parameters
1 testing transformer
Output voltage: 1.1 AC 0-10000 - v, DC 0-10000 - v;
1.2 the input voltage: 220 v
1.3 under the rated capacity, long-term continuous operation;
1.4 under the maximum output voltage, PD 1 PC or less;
1.5 noise 58 db (1 m position measurement) or less.
2 voltage regulator
2.1 the input voltage: 220 v;
2.2 nominal capacity: 2 kva, if any compensation, can be less than 15 kva, but not less than 10 kva);
2.3 under the rated capacity, long-term continuous operation;
2.4 noise acuities were 58 db (1 m position measurement);
2.5 the electric voltage regulation.
3 high voltage divider
3.1 high pressure arm capacitance: 1 nf;
3.2 compression ratio: 700 (can be discussed, combined with measuring control system);
3.3 under the rated capacity, long-term continuous operation;
3.4 under the maximum output voltage, PD 1 PC or less;
3.5 accuracy: 1%.
The computer control
4.1 bluetooth connection;
4.2 safety protection;
Voltage breakdown voltage electric resistance strength tester technical indicators:
The input voltage: ac 220 V output voltage: communication 0-100 KV; / dc 0-100 KV
Electric capacity: 10 kva high-pressure sizing: 0-100 kv step-up rate: 0.01 to 5.0 kv
(note: meet the standard requirements and can be set according to user requirements of different rate of pressure rise)
06, test method: ac/dc test: 1, 2, gradient booster 3 uniform booster, withstand voltage test
Test medium: air, oil test installation high sensitivity of over current protection device to ensure the sample breakdown within 0.05 S when cut off power supply. The instrument is equipped with advanced fault alarm system Avoid user operation fault instrument. Alarm (the upper machine and lower machine alarm)
Withstand voltage breakdown voltage of electric strength tester:
1, booster parts: consists of a voltage regulator and the high voltage transformer 0 ~ 50 kv booster section.
2, moving parts: uniform regulation voltage regulator by stepper motor to high voltage transformer voltage change.
3, test parts: measurement circuit composed of integrated circuit. Through the analog signal and the detection line switch signal to the computer.
4, computer software, by testing equipment acquisition through inligent circuit of measurement and control signals to the computer. Computer control equipment operation according to the collected information and process the test results.
5, test electrode: according to the national standard (1408.1-2006) with the equipment to provide three electrodes, specifications are: Ф two 25 mm x 25 mm; Ф a 75 mm x 25 mm. Except (build)