میگر یا تستر عایقی وسیله‌ای است برای اندازه گیری مقاومت‌های بسیار بزرگ معمولاً تا ۲ گیگا اهم با ولتاژ تست تا ۵ کیلوولت می‌باشد و جهت سنجش مقاومت عایقی کابل ها، موتورها، ترانسفورماتور‌ها، ژنراتور‌ها و سایر تجهیزات الکتریکی استفاده می‌شود.

درخشش الکتریک
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یکی از روش های کاهش مقاومت زمین به کمتراز 2 اهم، روش پنجه کلاغی است، که شکل اجرای این روش، در ادامه ارائه می شود. در این آرایش می‌توان هادی‌های از جنس و سطح مقطع هادی حفاظتی انتخاب نموده و آن‌ها را به صورت افقی و به شکل سه شاخه (پنجه کلاغی) در عمق حداقل ۷۰ سانتی متری از سطح زمین اجرا نمود و از یک سر به یکدیگر اتصال داد.

 

 

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به منظور حفاظت از جان افراد در مقابل خطر برق گرفتگی و جلوگیری از خطرات جریان نشتی از کلید‌های حفاظت از خطر برق
گرفتگی (محافظ جان) استفاده می‌شود. در این مقاله به راهنمای نصب و مشخصات کلید‌های محافظ جان می‌پردازیم.

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توالی سنج فاز در سیستم‌های صنعتی و نگه داری سیستم‌های الکتریکی که به طور دائم کار میکنند و همچنین تعیین جهتگردش موتور از طریق چگونگی ارتباط ترمینال‌ها اهمیت فراوانی دارند که در این بخش در مورد آن‌ها توضیح داده شده است.

ادامه مطلب...

قفس فارادی یک ققس یا فضای بسته ساخته‌شده از فلز یا رسانای الکتریکی دیگر است، که در ادامه به توضیحات بیشتری می پردازیم.
ادامه مطلب...

جریان زیاد (overcurrent) هر جریانی بیش از جریان نامی هادی ها، تجهیزات و یا دستگاه‌ها در شرایط مورد استفاده است. اصطلاح "جریان زیاد" هم جریان اتصال کوتاه (short circuit current) و هم جریان اضافه بار (overload current) را شامل می‌شود.
ادامه مطلب...
آیا برق تلفن همان برق شهر است ؟
آیا برق تلفن همان برق شهر است؟ پس چرا انسان را نمی گیرد؟ برق تلفن مستقل از برق شهر بوده و ربطی به آن ندارد. برای همین است که در زمان خاموشی تلفن کار می کند. برق تلفن از نوع مستقیم بوده اما برق شهر از نوع متناوب است.
ادامه مطلب...
مدار الکتریکی قدرت و فرمان راه اندازی الکتروموتورهای سه فاز آسنگرون روتور قفسه ای توسط کنتاکتور به صورت اتصال دائم ،کنترل از دو نقطه برای کنترل یک موتور از دو نقطه استفاده می شود. این مدار بسیار شبیه به مدار کنترل از یک نقطه می باشد و می توان آن را به نوعی تعمیم یافته مدار اتصال از یک نقطه دانست.

ادامه مطلب...

عملیات گودبرداری محل ساخت راکتور واحد دوم نیروگاه اتمی بوشهر فردا با حضور رئیس سازمان انرژی اتمی ایران و رئیس روس اتم آغاز می‌شود. هر یک از این واحد‌ها هزار و ۵۷ مگاوات برق تولید خواهد کرد.
ادامه مطلب...
هوشنگ فلاحتيان با بيان اينكه سازمان انرژي‌هاي نو ايران تعرفه‌هاي خريد برق از نيروگاه‌هاي زباله سوز را اعلام كرده است گفت: اين وزارتخانه مي‌تواند برق توليدي شهرداري تهران را خريداري كند.
ادامه مطلب...
مرورگر شما بسیار قدیمی است!
جهت مشاهده این وب سایت به صورت صحیح، بروزرسانی مرورگرتان ضروری خواهد بود. بروزرسانی مرورگر
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