(1) Independent lightning protection grounding resistance is≤ 10Ω.
(2) Independent safety protection grounding resistance should be less than or equal to 4Ω.
(3) Independent AC grounding resistance is ≤ 4Ω.
(4) Independent DC grounding resistance is ≤ 4Ω.
(5) Anti-static grounding resistance is generally required as ≤ 100Ω.
(6) Public grounding body (combined grounding) grounding resistance shall not be greater than 1 Ohm.
(7) Traction substation main grounding network grounding resistance should not be greater than 0.5Ω. Independent lightning rod grounding should be separated from the main grounding network, and the groudning resistance of the grounding resistance test meter is not greater than 10Ω.
(1) When the sensitivity of the vibrating mirror is too high, the potential probe can be inserted into the shallow soil. When the sensitivity of the oscillator is not enough, you can inject water along the potential probe and current probe. When the earth interference signal is strong, you can change the speed of the hand crank generator to improve the anti-interference ability and obtain stable readings.
(2) When the distance between the grounding pole e' and the current probe C' is greater than 40m, the position of the potential probe P' can be inserted a few meters from the middle line of E'C', and the measurement error can be ignored. When the distance between the grounding pole e' and the current probe C' is less than 40m, the position of the potential probe P' can be inserted into the middle of the straight line between E' and C'.
(3) In measurement, grounding resistance test meter should be placed smoothly. When shaking the handle, the instrument should be pressed so as not to cause strong artificial shaking, so as not to mistakenly believe that the pointer can not be adjusted to the zero center line.
(4) To ensure the reliability of the measurement results, it is necessary to move the position of the two probes after one measurement and repeat the measurement in the other direction. Generally, each time the measured resistance value is not exactly the same, you can take the average of multiple measurements as the final value.
(5) Prohibit the measurement when there is lightning or the object under test is charged. Grounding resistance test meter prohibit open circuit test, when not in use should be the terminal with bare wire short.
(6) The instrument should be handled and used carefully and gently, to avoid violent vibration.
(7) After each measurement, the probe should be wiped clean after pulling out, and organize the wire for the next use. Store the grounding resistance test meter in a dry, light-proof and vibration-free place.
Techwin grounding resistance test meter is specially designed for online monitoring of the grounding network resistance of lightning protection devices. It can be installed individually or assembled into a wired network and wireless network system. It can be used for wired or wireless communication. It can be externally powered or equipped with solar power. It is equipped with a standard RS485 interface for data communication and can provide a custom programming interface for customers to interface with other private protocols.
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