【Daily Question 20090209】What are the requirements for grounding the shielding layer of a shielded conductor? Why?
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What are the requirements for grounding the shielding layer of shielded conductors? Why? Answer: The shielding layer should be grounded at one end and left ungrounded at the other; the grounding point can be located at the electronic device or at the sensing element, depending on the desired anti-interference effect. If both sides are grounded, the shielding layer forms a circuit with the ground, and common-mode interference signals can enter the electronic device through the distributed capacitance between the wires and the shielding layer, causing interference. However, if one end is grounded and only one side remains at the same potential, the shielding layer does not form a circuit with the ground, so no interference signals can enter the electronic device, thereby preventing the intrusion of common-mode interference voltages from the ground. This post was last edited by Mobei Yihai on 2009-2-9 20:19.]
The shielding layer should be grounded at one end and left ungrounded at the other; the grounding point can be located at the electronic device or at the sensing element, depending on the desired anti-interference effect. If both sides are grounded, the shielding layer forms a circuit with the ground, and common-mode interference signals can enter the electronic device through the distributed capacitance between the wires and the shielding layer, causing interference. However, if one end is grounded and only one side remains at the same potential, the shielding layer does not form a circuit with the ground, so no interference signals can enter the electronic device, thereby preventing the intrusion of common-mode interference voltages from the ground. This post was last edited by Mobei Yihai on 2009-2-9 15:21.]
The shielding layer should be grounded at one end and left ungrounded at the other; the grounding point can be located at the electronic device or at the sensing element, depending on the desired anti-interference effect. If both sides are grounded, the shielding layer forms a circuit with the ground, and common-mode interference signals can enter the electronic device through the distributed capacitance between the wires and the shielding layer, causing interference. However, if one end is grounded and only one side remains at the same potential, the shielding layer does not form a circuit with the ground, so no interference signals can enter the electronic device, thereby preventing the intrusion of common-mode interference voltages from the ground.
The shielding layer should be grounded at one end and left ungrounded at the other; the grounding point can be located at the electronic device or at the sensing element, depending on the desired anti-interference effect. If both sides are grounded, the shielding layer forms a circuit with the ground, and common-mode interference signals can enter the electronic device through the distributed capacitance between the wires and the shielding layer, causing interference. However, if one end is grounded and only one side remains at the same potential, the shielding layer does not form a circuit with the ground, so no interference signals can enter the electronic device, thereby preventing the intrusion of common-mode interference voltages from the ground.
The installation requirements for shielded cables specify that one end of the shielding layer should be grounded, while the other end should remain ungrounded. If both ends of the shield wire are grounded at the same time, common-mode interference signals can enter electronic devices through the distributed capacitance between the wires and the shield layer, introducing interference signals; in severe cases, this can prevent the electronic devices from functioning, posing a serious threat!