I'll like to add a bit. for a 132 kV line, let's calculate the ratings: for a 10 percent voltage regulation, the voltage will be 145 kV, for any surge/lightning arrestor, we need to calculate 2 voltages: 1. MCOV : max. countinuous over voltage 2.Rated voltage 1. MCOV : max. countinuous over voltage This is the continuous operating (nominal) voltage per phase that will be available to LA during normal operation. to calculate: 145/sqrt(3) = 145/1.732 = 83.72 kV This is the minimum MCOV you need. if exact value is not available in the market, select the closet one (higher). e.g. 90 kV 2. Rated voltage This is the maximum voltage the LA can withstand for 10 seconds without shorting the surge to the ground. to calculate, we need peak of the voltage: 83.72 * sqrt(2) = 83.72*1.414 = 118.4 kV available in the market is 120 kV for complete details, please refer to IEC standard 60044.
Explanation is impressive but the logic behind selection of LA rated voltage lower than system voltage is not correct. Infact name plate rated values(30kV, 120kV etc) are phase values and should be greater than max system voltage(33*1.1/1.73kV,132*1.1/1.73kV etc).please refer IEEEC62 or IEC standards for insulation coordination for details.
Hello sir, very nice video. Please make a video on calculation for designing a surge protection device for domestic appliances (like a secondary surge device which we can use in home appliances) using MOV, TVS, GDT.
Sir I have one doubt system voltage 132kv means L.A connected only phase so the voltage level of the LA only 76.21kv... As per your explanation lightning selected low insulation path means 120kv is not less...
Thanku for ur feed back sir, 1)132 KV is system design voltage. 2)76.21is phase individual voltage of each line individual phase and design volteg is two different things.i am explain about the design system voltage and accroding to them we will use 120 KV LA. As per equipment individual volteg of 76.21 for metering and protections perpous. Thanku for ur feed back
Please see the graph of search wave u have drawn which is wrongly represented by 50/1 micro sec, it will be 1/50 micro sec.... Which means the first peak will reach within 1 micro sec and the tail will reach 50% of the peak at 50 micro sec i.e. T1/T2 is 1/50 micro sec wave. Please rectify the mistake, otherwise students will be misguided.
Not clear about selecting voltage rating of L.A. It should be max. pjase voltage of a line plus 10% extra.. To obtain L.A for 25kv overhead line in traction system , it should be 42kv l.a
@@sarojgarhwal23 also request you elaborate role of coeffiecient of earthing(i.e effectively and non-effectively earthed system) while deciding rating of L.A.
if we select LA rating as 10% less of rated voltage, then in normal operation condition also LA will operate right?
I'll like to add a bit.
for a 132 kV line, let's calculate the ratings:
for a 10 percent voltage regulation, the voltage will be 145 kV,
for any surge/lightning arrestor, we need to calculate 2 voltages:
1. MCOV : max. countinuous over voltage
2.Rated voltage
1. MCOV : max. countinuous over voltage
This is the continuous operating (nominal) voltage per phase that will be available to LA during normal operation. to calculate:
145/sqrt(3) = 145/1.732 = 83.72 kV
This is the minimum MCOV you need. if exact value is not available in the market, select the closet one (higher). e.g. 90 kV
2. Rated voltage
This is the maximum voltage the LA can withstand for 10 seconds without shorting the surge to the ground. to calculate, we need peak of the voltage:
83.72 * sqrt(2) = 83.72*1.414 = 118.4 kV
available in the market is 120 kV
for complete details, please refer to IEC standard 60044.
Superb
@@sarojgarhwal23 thanks
Good sir
Thanks and welcome
What was your biggest takeaway from the video?
Did you learn anything new?
What was your favorite part
Explanation is impressive but the logic behind selection of LA rated voltage lower than system voltage is not correct. Infact name plate rated values(30kV, 120kV etc) are phase values and should be greater than max system voltage(33*1.1/1.73kV,132*1.1/1.73kV etc).please refer IEEEC62 or IEC standards for insulation coordination for details.
Thanku for ur feed back sir 🙂
I know, it's only for better understanding..
Thank u bro..for sharing such an informative video..
Hello sir, very nice video. Please make a video on calculation for designing a surge protection device for domestic appliances (like a secondary surge device which we can use in home appliances)
using MOV, TVS, GDT.
Yes soon I will upload
You are c&s electric engineer ???
I am from engineering design department
Sir normal arrestar Kitna area cover karta hai
how do i contact u for installation ...?
Thanku for approach but, I am from engineering design department.
Thanks sir
Very helpful 👌👌.pls make next video on it's types and testing. Also include it's healthy testing value and unhealthy testing values...
th-cam.com/video/RK67DSvu19U/w-d-xo.html
Good ...Keep it up dude
Thanks
Useful video
Thanku
Sir I have one doubt
system voltage 132kv means L.A connected only phase so the voltage level of the LA only 76.21kv...
As per your explanation lightning selected low insulation path means 120kv is not less...
Thanku for ur feed back sir,
1)132 KV is system design voltage.
2)76.21is phase individual voltage of each line
individual phase and design volteg is two different things.i am explain about the design system voltage and accroding to them we will use 120 KV LA.
As per equipment individual volteg of 76.21 for metering and protections perpous.
Thanku for ur feed back
Sorry sir its my mistake... Im not think about lightning... Again i watched vedio... Now i get some +++++....
@@bharathi6898 thanku sir,
You are alway welcome for ur valuable feedback 👌👌
Please see the graph of search wave u have drawn which is wrongly represented by 50/1 micro sec, it will be 1/50 micro sec.... Which means the first peak will reach within 1 micro sec and the tail will reach 50% of the peak at 50 micro sec i.e. T1/T2 is 1/50 micro sec wave. Please rectify the mistake, otherwise students will be misguided.
Let me check,
Thanku for ur fed back
Very good explanation saroj... keep it up 👍
thanku sir
As a German, I would love to hear this in English. Please.
Ok soon I will upload
Very nice sir
eng subtitle please sir
Ok
Parts kn darkar
+subash ch swain subash
Not clear about selecting voltage rating of L.A. It should be max. pjase voltage of a line plus 10% extra.. To obtain L.A for 25kv overhead line in traction system , it should be 42kv l.a
Selecting of LA for traction system is different procedures,I will upload new video for the same
@@sarojgarhwal23 also request you elaborate role of coeffiecient of earthing(i.e effectively and non-effectively earthed system) while deciding rating of L.A.
Ok
poda thaayoli
+Manoj Kumar meams