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Creepage distance means the shortest distance along the surface of a solid insulating material between two conductive parts. A creepage distance cannot be less than the associated clearance so that the shortest creepage distance possible is equal to the required clearance.
How do you calculate creepage distance?
How to Determine Creepage Distance for Connectors Creepage Distance/Air Gap: The Path of Least Resistance. Check the Pins on the Connector Face. Check the Backside of the Connector: Check Female Contacts as well: Check For Hidden Creepage Paths Inside the Connector. Check for Hidden Creepage Paths Outside the Connector.
What is the creepage and clearance distance?
Clearance: In the “line of sight” distance or the shortest air path between two conductors. The shortest distance that can achieve insulated through the air. Creepage: The shortest distance between two conductors along the insulating surface.
What is creepage distance Mcq?
ANSWER: Shortest distance between two conducting parts along the surface of the insulating material.
What is the importance of creepage distance?
A proper and adequate creepage distance protects against tracking, a process that produces a partially conducting path of localized deterioration on the surface of an insulating material as a result of the electric discharges on or close to an insulation surface.
Is standard for creepage distance?
Specifically, creepage is the shortest distance between the path of two conductive parts of a medical device and is measures along the surface of insulation. The clearance is similar, but very different. It [creepage] is the shortest distance between two conductive parts, measured through air.
What is creepage distance in PCB?
Creepage – Creepage is the shortest distance to another conductor along the surface of the insulating material of your PCB. This is because at higher voltages conductors can arc to one another or to other components if they’re too close together.
What is flashover distance?
Strike distance is simply the shortest distance between the end fittings of the insulator in the surrounding medium. It is also sometimes referred to as the dry arc distance, flashover distance, or tight string distance. The higher the operating voltage, the greater strike distance you will need.
What is the minimum safe distance from power lines?
Work at a safe distance This is the most important rule: Work at a safe distance from all power lines. The Occupational Safety and Health Administration (OSHA) requires that equipment be kept at least 10 feet away from power lines with voltages up to 50kV.
What are the types of insulators?
A look at some types of insulators and the conditions under which they are deployed. Pin-type insulators. Line post insulators. Suspension insulators. Strain insulators. Shackle insulators. Post insulators. Cap and pin insulators. Stay insulators.
What DAR value indicates poor insulation?
The dielectric absorption ratio (DAR) is one of them, which describes the ratio of two time-resistance values. A DAR < 1 indicates that the IR at a larger timescale is smaller than that at a shorter timescale. This means that absorption current is masked by leakage current, in turn indicating poor insulation.
What type of insulation is preferred for DC smoothing reactors?
Oil is preferred for DC smoothing Reactors.
Which material is used for indoor bus bar?
ANSWER: Copper rods.
What is creepage current?
CREEPAGE: The shortest path between two conductive parts, or between a conductive part and the bounding surface of the equipment, measured along the surface of the insulation (Figure 2). One additional term that is related to these definitions in a high voltage design is “bounding surface.”.
What is creepage factor?
Creepage Factor (CF), is a global check of the overall density of creepage distance and is equal to l/A where: l is the total creepage distance of the insulator and A is the arcing distance of the insulator. For disc insulators the CF is determined for a string comprising at least 5 insulator units.
What do you mean by creepage distance of an insulator?
Creep distance is sometimes referred to as leakage distance. It represents the shortest distance along the surface of the insulator between the conductive ends of the insulator. In a typical insulator application, one end would be at an elevated voltage level and the other end would be at a lower voltage or grounded.
What is clearance distance?
Clearance is the shortest distance in air between two conductive parts. Creepage distance means the shortest distance along the surface of a solid insulating material between two conductive parts.
What is creepage test?
Creepage & Clearance distances form part of the product’s electrical insulation system that protects the user from a Risk of Shock. Purpose of the Test: To verify that there is adequate insulation between electrical parts, to withstand the rigors of normal use, over the life of the product.
What is tracking in electrical?
Tracking is defined as a process that produces localised irreversible deterioration on the surface of an insulator, resulting in the loss of the insulating function by the formation of a conductive path on the surface of the insulator.
What is the 3W rule?
If you’ve ever wondered how far you need to keep your traces from each other to minimize coupling, then use the 3W rule. It states that the separation between traces must be three times the width of a single trace when measured from center to center.
What is PCB voltage?
Although power supply circuit boards are classified according to their output voltage and power. There is no universally accepted definition for high voltage; however, the generally accepted level for industrial circuitry is ≥ 100V (AC or DC).
What is electrical clearance?
The electrical clearance is the electrical isolation between two conductive components, whereas the creepage indicates the conduction of electricity across the surface of a nonconductive component. The clearance and creepage distance are two important parameters while designing an electrical assembly.
What are the signs of a flashover?
Signs of an impending flashover Ambient temperatures quickly double and triple as hoselines are advanced. Large volumes of heavy dark smoke. Rollover: active flame circulation in the thermal layer. Free burning fire in a ventilation-deficient environment.
What is flashover test?
Impulse frequency flashover test An impulse voltage generator which generates a very high voltage at a frequency of several hundred kilohertz is connected to the insulator. This voltage is applied to the insulator and spark-over voltage is noted.
What is dry arcing distance?
Dry arcing distance is the shortest distance outside the insulator along the air not along the insulator body and between those parts which normally have the operating voltage between them. Arcing distance is also called as flash over distance.
