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ThereIf there is possible leakage to earth leakage in your system.

For example an RCCB rated 100 mA, nominal voltage 240 Vac.

Since R = 240 V R=240V/ 100 mA100mA = 2.4 k&ohm4kΩ, this is the minimum resistance at 240V before your 100 mA100mA RCCB could trip. If your resistance drops below 2.4 kΩ4kΩ; (for example 2.3 kΩ3kΩ;), since I =VI=V/R this current passing through RCCB is 104 mA, already exceeding, and voila it trips the RCCB. This is the situation if it trips without lightning.

In the same way if voltage is coming from lightning, it could be 40 kV, while your resistance is only 300 kΩ300kΩ. I = 40 kV I=40kV/ 300 kΩ = 133300kΩ; I=133 mA, which already can cause your RCCB to trip.

My suggestion is to check any leakage that could possibly less than 400 kΩ400kΩ. Normally, ensure your insulation resistance is more than 1 MΩ.1MΩ

There is possible leakage to earth.

For example an RCCB rated 100 mA, nominal voltage 240 Vac.

Since R = 240 V / 100 mA = 2.4 k&ohm, this is the minimum resistance at 240V before your 100 mA RCCB could trip. If your resistance drops below 2.4 kΩ (for example 2.3 kΩ), since I =V/R this current passing through RCCB is 104 mA, already exceeding, and voila it trips the RCCB. This is the situation if it trips without lightning.

In the same way if voltage is coming from lightning, it could be 40 kV, while your resistance is only 300 kΩ. I = 40 kV / 300 kΩ = 133 mA, which already can cause your RCCB to trip.

My suggestion is to check any leakage that could possibly less than 400 kΩ. Normally, ensure your insulation resistance is more than 1 MΩ.

If there is earth leakage in your system.

For example an RCCB rated 100 mA, nominal voltage 240 Vac.

Since R=240V/100mA = 2.4kΩ, this is the minimum resistance at 240V before your 100mA RCCB could trip. If your resistance drops below 2.4kΩ; (for example 2.3kΩ;), since I=V/R this current passing through RCCB is 104 mA, already exceeding, and voila it trips the RCCB. This is the situation if it trips without lightning.

In the same way if voltage is coming from lightning, it could be 40 kV, while your resistance is only 300kΩ. I=40kV/300kΩ; I=133 mA, which already can cause your RCCB to trip.

My suggestion is to check any leakage that could possibly less than 400kΩ. Normally, ensure your insulation resistance is more than 1MΩ

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edit approved Jan 29, 2023 at 2:35
Matt S
edit approved Jan 29, 2023 at 2:35
Matt S
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There is possible leakage to earth. This is explanation if you interested to know. from V=IR. for

For example an RCCB Rated 100mA.rated 100 mA, nominal voltage 240Vac240 Vac. R=V/I >

Since R = 240V240 V /100mA 100 mA = 2.4kOhm4 k&ohm, this is the minimum resistance @240Vat 240V before you 100mAyour 100 mA RCCB could trip. If your resistance dropdrops below 2.4kOhm4 kΩ (for example 2.3kOhm3 kΩ), since I =V/R this current passing through RCCB is 104mA104 mA, already exceedexceeding, and voila tripit trips the rccbRCCB. thisThis is the situation if it triptrips without lightning.

inIn the same way if voltage is coming from lightning., it could be 40kV. while you40 kV, while your resistance is only 300kOhm300 kΩ. I = 40kV40 kV /300kOhm 300 kΩ = 133mA.133 mA, which already can cause your RCCB to trip. my

My suggestion is to check any leakage that could possibly less than 400kOhm400 kΩ. Normally, ensure your insulation resistance is more 1Mohmthan 1 MΩ.

There possible leakage to earth. This is explanation if you interested to know. from V=IR. for example RCCB Rated 100mA. nominal voltage 240Vac. R=V/I > R = 240V/100mA = 2.4kOhm minimum resistance @240V before you 100mA RCCB could trip. your resistance drop below 2.4kOhm example 2.3kOhm, I =V/R this current passing through RCCB is 104mA already exceed and voila trip the rccb. this is situation if it trip without lightning.

in the same way if voltage coming from lightning. it could be 40kV. while you resistance only 300kOhm. I = 40kV/300kOhm = 133mA. already can cause your RCCB trip. my suggestion is check any leakage that could possibly less than 400kOhm. Normally ensure your insulation resistance more 1Mohm.

There is possible leakage to earth.

For example an RCCB rated 100 mA, nominal voltage 240 Vac.

Since R = 240 V / 100 mA = 2.4 k&ohm, this is the minimum resistance at 240V before your 100 mA RCCB could trip. If your resistance drops below 2.4 kΩ (for example 2.3 kΩ), since I =V/R this current passing through RCCB is 104 mA, already exceeding, and voila it trips the RCCB. This is the situation if it trips without lightning.

In the same way if voltage is coming from lightning, it could be 40 kV, while your resistance is only 300 kΩ. I = 40 kV / 300 kΩ = 133 mA, which already can cause your RCCB to trip.

My suggestion is to check any leakage that could possibly less than 400 kΩ. Normally, ensure your insulation resistance is more than 1 MΩ.

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Epe
Epe
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There possible leakage to earth. This is explanation if you interested to know. from V=IR. for example RCCB Rated 100mA. nominal voltage 240Vac. R=V/I > R = 240V/100mA = 2.4kOhm minimum resistance @240V before you 100mA RCCB could trip. your resistance drop below 2.4kOhm example 2.3kOhm, I =V/R this current passing through RCCB is 104mA already exceed and voila trip the rccb. this is situation if it trip without lightning.

in the same way if voltage coming from lightning. it could be 40kV. while you resistance only 300kOhm. I = 40kV/300kOhm = 133mA. already can cause your RCCB trip. my suggestion is check any leakage that could possibly less than 400kOhm. Normally ensure your insulation resistance more 1Mohm.