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How to Measure Electric Motor Insulation Resistance

To prolong the life of electrical systems and motors, regular insulation resistance testing is required. Over the years, after many cycles of operation, electric motors are exposed to environmental factors such as dirt, grease, temperature, stress, and vibration. These conditions can lead to insulation failure, resulting in loss of production or even fires.

An effective motor insulation resistance system has high resistance, usually (at an absolute minimum) greater than a few mega ohms (MΩ).  A poor insulation system has lower insulation resistance. The optimal insulation resistance for an electric motor is often determined by the manufacturer’s specifications, the criticality of the application where the motor is used, and the environment where it is located.

It is practically impossible to
determine rules for the actual minimum insulation resistance value of an electric motor because resistance varies according to method of construction, condition of insulation material used, rated voltage, size and type. A general rule-of-thumb is 10 Megohm or more. The insulation system of an electrical motor is said to be in good condition if:


Measured Insulation resistance is greater than or equal to 10MΩ

Typical Insulation Resistance Level for Electric Motors
There are no rules for determining the minimum insulation resistance value for a motor. Most data available are empirical. The ones listed below are from grundfos, a leading manufacturer of electrical motors:

Insulation Resistance Level
Insulation Level

2MΩ or Less To prolong the life of electrical systems and motors, regular insulation resistance testing is required. Over the years, after many cycles of operation, electric motors are exposed to environmental factors such as dirt, grease, temperature, stress, and vibration. These conditions can lead to insulation failure, resulting in loss of production or even fires.

An effective motor insulation resistance system has high resistance, usually (at an absolute minimum) greater than a few mega ohms (MΩ).  A poor insulation system has lower insulation resistance. The optimal insulation resistance for an electric motor is often determined by the manufacturer’s specifications, the criticality of the application where the motor is used, and the environment where it is located.

It is practically impossible to
determine rules for the actual minimum insulation resistance value of an electric motor because resistance varies according to method of construction, condition of insulation material used, rated voltage, size and type. A general rule-of-thumb is 10 Megohm or more. The insulation system of an electrical motor is said to be in good condition if:


Measured Insulation resistance is greater than or equal to 10MΩ

Typical Insulation Resistance Level for Electric Motors
There are no rules for determining the minimum insulation resistance value for a motor. Most data available are empirical. The ones listed below are from grundfos, a leading manufacturer of electrical motors:

Insulation Resistance Level
Insulation Level

2MΩ or Less
Bad
2 - 5MΩ 
Critical
5 - 10MΩ
Abnormal

10 - 50MΩ 
Good
50 - 100MΩ
Very Good
100MΩ or More 
Excellent

How to Measure Insulation Resistance of a Motor
The measurement of insulation resistance is carried out by means of a mega ohmmeter – a high resistance range ohmmeter. To measure insulation resistance, a DC voltage of 500V or 1000V is applied between the windings and the ground of the motor
During the measurement and immediately afterwards, do not touch any terminals of the motor as some of them carry dangerous voltages that may be fatal.
The minimum insulation resistance of motor measured to ground at 500V can be measured at a winding temperature of  -15°C – 20°C. The maximum insulation resistance can be measured at 500V with operating windings temperature of 80-120°C depending on the motor type and efficiency

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महानगरपालिका ,उप-महानगरपालिका र नगरपालिका गठन हुन चाहिने आधारहरु :-

महानगरपालिका ,उप-महानगरपालिका र नगरपालिका गठन हुन चाहिने आधारहरु :- ===========¥¥============ 1.महानगरपालिका गठनका आधारः- + कम्तीमा 3 लाख जनसंख्या + कम्तीमा वार्षिक रु 40 करोड आम्दानी + विद्युत्,खानेपा नी, सञ्चारको उपयुक्त सुविधा + नगरको प्रमुख सडकका साथै अन्या शाखा सडकहरु समेत पक्की भएको हुनु पर्ने + स्वास्थ्य सेवा सम्बन्धी विशिष्ठ प्रकृतिको सेवाको उपलब्धता + अन्तराष्ट्रिय खेलकुद कार्यक्रम आयोजनाका लागि आवश्यक पूर्वाधारको उपलब्धता + उच्च शिक्षाका लागि विभिन्न विषयहरुमा पर्याप्त अवसरको उपलब्धता र कम्तीमा एउटा विश्वविद्यालयको गठन + उच्च थप पर्याप्त शहरी सुविधाको उपलब्धता 2. उप-महानगरपालिका गठनका आधारः- + कम्तीमा 1 लाख जनसंख्या +कम्तीमा रु 10 करोड रुपैयाँ वार्षिका आम्दानी + नगरका प्रमुख सडकहरु पक्की भैसकेको हुनुपर्ने + विद्युत्, खानेपानी र सञ्चारको उपयुक्त सुविधा + उच्च गुणस्तरीय शिक्षा तथा सेवाको सुविधाको उपलब्धता + राष्ट्रिय तथा अन्तराष्ट्रिय स्तरको खेलकुद कार्यक्रमको लागि सामान्य व्यवस्था + सार्वजानिक उद्यानहरु र नगर सभागृहको व्यवस्था + अन्य अत्यावश्यक

नेपालमा जातजाति

नेपालमा जातजाती नेपाली बृहत शब्दकोषका अनुसार वंशपरम्परा, धर्म, गुण, आकृति, वासस्थान आदिका आधारमा विभाजित मनुष्यको वर्गलाई जात भनिन्छ भने शारीरिक बनावट आकार, प्रकार गुण, स्वभाव आदिका आधारमा छुट्टीने वा चिनिने जातीय विभाग, समूह वा वर्गलाई जाति भनिन्छ । यस्ता जात जातिले आफ्नै विशेष प्रकारका धर्म, नियम, संस्कारको पालना गरेका हुन्छन् । सामान्यतया यस्ता जातजातिको छुट्टै भाषा, भेषभुषा हुन्छ । वैवाहिक सम्बन्ध एउटै जातजाति भित्र हुने गर्दछ । नेपालमा विभिन्न प्रकारका जातजातिहरूको बसोवास भएको छ । त्यसैले नेपाली समाजलाई वहुल समाजको रूपमा चिनिन्छ । नेपालमा भएका जातजातिहरूलाई ब्राह्मण, क्षेत्री, वैश्य र सुद्र गरी ४ भागमा वर्गीकरण गरेको छ  ।    आदिवासी/जनजाति  आदिबासी जनजाति उत्थान राष्ट्रिय प्रतिष्ठान ऐन, २०५८ अनुसार “आदिबासी जनजाति भन्नाले आफ्नो मातृभाषा र परम्परागत रीतिरिवाज, छुट्टै सांस्कृतिक पहिचान, सामाजिक संरचना र लिखित वा अलिखित इतिहास भएको अनुसूची बमोजिमको जाति वा समुदाय सम्झनु पर्दछ  ।” जनजातिका विशेषताहरूलाई बुँदागत रूपमा भन्दाः  • जसको छुट्टै आफ्नै सामूहिक सांस्कृतिक पहिचान छ  

बिभिन्न जातिका पुरोहितहरु-:

बिभिन्न जातिका पुरोहितहरु-: ==========¥¥============ १. ब्रहामण, क्षेत्री – पण्डित, पुरोहित २. तामाङ – लामा, बोपो ३. थारु – भर्रा, गुरुवा ४. नेवार – देउभाजु, गुभाजु ५. राई –ङोपा ६. लिम्बु – फेदाङमा, शाम्बा ७. चेपाङ – फाल, पाँडे ८. सुनुवार – नासो ९. जिरेल – नाक्सो १०. गुरुङ – घ्याव्रे, घ्याप्रिङ् ११. मगर – भुषाल