Basic knowledge about surge protectors
Basic knowledge about surge protectors
Surges and Transients A voltage surge is a temporary rise in voltage and current on a circuit. They have voltage ranges greater than 2000 volts and current ranges greater than 100 amps. Typical rise times are in the 1 to 10 microsecond range. Transients or surges are the most common power supply problems, and their destructive moments can cause significant damage such as electrical or electronic equipment failure, frequent outages, data loss, lost time, and business downtime.
Where does the surge come from?
The main cause of damage to electronic equipment caused by surges is lightning strikes. The greatest damage is not caused by a direct lightning strike, but is the result of transient voltage and current surges on power, telecommunications, or radio frequency transmission lines caused by the strong electromagnetic fields generated during a lightning strike. A more common cause of power surges is high-power electrical equipment (such as elevators, air conditioners, and refrigerators) operating by turning on their compressors and motors. Other sources of surges include faulty wiring, utility power failures, and electrical noise.
What is a Dikai Technology surge protector?
A surge protector also known as a Transient Voltage Surge Suppressor (TVSS), Surge Protector Device (SPD) or Surge Suppression Equipment (SSE) is a device designed to protect electrical and electronic equipment from electrical surges and Voltage spikes. Surge protectors divert excess voltage and current from transients or surges into the ground conductor.
How surge protectors work
Diverts excess voltage and current from transients or surges into the ground wire and prevents it from flowing through electrical and electronic equipment while allowing normal voltage to continue along its path. This excess energy can cause damage to electrical and electronic equipment and process control instrumentation.
Two main functions of a surge protector
1. Provides a low impedance path for conducting large amounts of current to eliminate excess voltage.
2. Absorbs and diverts excess current to ground to protect against the effects of transients or surges.
Types of surge protectors: There are two types of surge protectors
A filter is a device that acts as a barrier to high frequency currents (usually noise) while allowing low frequency power currents to pass through unaffected.
A transient shunt is a device that provides a very low impedance path to ground whenever the voltage across the device exceeds a certain value, but reduces the voltage that may be presented to sensitive equipment.
Surge Protector Components Components used to reduce or limit high voltages typically include MOVs, gas discharge tubes, silicon avalanche diodes, etc. or a combination of these components. Each of these components is a different function.
MOV (metal oxide varistor) is composed of zinc oxide material, which is a semiconductor with variable resistance. Under normal conditions, the MOV behaves as a high-impedance device, but when the voltage is too high, the MOV's resistance drops rapidly to provide a low-impedance flow path. An MOV has a limited life expectancy and will degrade when exposed to a few large transients or many smaller transients. MOVs are the most common component in AC surge protectors.
Gas discharge tubes (GDTs) divert excess current from the hot wire to the ground wire by using an inert gas as a conductor. Under normal conditions, the noble gas acts as a poor conductor, but when the voltage is higher than an acceptable level, the noble gas becomes ionized into an effective conductor, passing the current to ground until the voltage returns to normal levels. The GDT will conduct electricity at a voltage lower than the high voltage of the ionized gas and will be able to conduct more current than other components. GDTs have a limited life expectancy and can withstand a few very large transients or many more smaller transients.
Silicon avalanche diodes (SAD) provide perfect confinement of the protective element, but have lower current capabilities. When the voltage increases above the extreme level, the SAD will tolerate avalanche breakdown causing the voltage to conduct to ground.
Other important components, such as resistors, capacitors and/or inductors, are used in conjunction with the protective components mentioned above.
Why do you need a surge protector?
Today, many of the electronic components in modern electrical equipment are smaller, more delicate, and more sensitive to increases in electrical current. Microprocessors, which are part of all computers and many modern electrical devices, are particularly sensitive to surges. Your electrical equipment can be affected by damaging surges on AC power lines and telephone or signal lines.
Surge protectors are suitable for all applications connected to electrical power (utility or locally generated), telephone lines (such as modem, fax, data, etc.), computer data lines, communication lines, etc., as follows:
Computers and peripherals such as printers, monitors, speakers, fax machines and modems, etc.
PABX and communication equipment, etc.
entertainment components
Medical equipment, surgical equipment, scientific equipment, etc.
Weighing bridges and measuring equipment, etc.
Electrical Equipment
security system
Surge protector location
Surge protectors are typically applied at multiple points throughout a facility. National standards define three categories of surge levels based on strategic locations within a facility's cabling network where power problems may be encountered. They categorize surge protector types, potential effects of transient surges or spikes, and location.
Class A: Defined as any outlet and long branch circuit extending more than 10 meters (30 feet) from a Class B location or more than 20 meters (60 feet) from a Class C location. Surge protectors in this location category are for use at the outlet or individual circuit level and are intended to protect specific equipment such as computers, counterweight bridges, measuring equipment, process control equipment, DC power supplies, etc.
Class B: Defined as all main sub-feeders, bus systems and short branch circuits in large buildings, such as switchboards, industrial bus and feeder systems, heavy electrical circuits, lighting systems. Protection at this location is very effective in suppressing more frequent internally generated transients, changing transient conditions, especially sensitive equipment and equipment powered from substations.
Class C: Defined as external and main service entrances including main supply lines, transformers, service connections and feeders to the main service entrance panel, any overhead or sub-feeders, underground wiring to well pumps. This type of surge protector is used to protect against externally caused power interruptions. This device will help prevent lightning strikes from entering the facility through power lines.
These three categories A, B and C determine which surge protector or TVSS should be used at which location.