Surge Protective Device OEM

The ability of an surge protective device OEM to limit overvoltages on the electrical distribution network by diverting surge currents is a function of the surge-protective components, the mechanical structure of the surge protective device OEM, and the connection to the electrical distribution network. An surge protective device OEM is intended to limit transient overvoltages and divert surge current, or both. It contains at least one nonlinear component. In the simplest terms, surge protective device OEMs are intended to limit transient overvoltages with a goal of preventing equipment damage and downtime due to transient voltage surges reaching the devices they protect. For example, consider a water mill protected by a pressure relief valve. The pressure relief valve does nothing until an over-pressure pulse occurs in the water supply. When that happens, the valve opens and shunts the extra pressure aside, so that it won’t reach the water wheel. If the relief valve was not present, excessive pressure could damage the water wheel, or perhaps the linkage for the saw. Even though the relief valve is in place and working properly, some remnant of the pressure pulse will still reach the wheel. But pressure will have been reduced enough not to damage the water wheel or disrupt its operation. This describes the action of surge protective device OEMs. They reduce transients to levels that will not damage or disrupt the operation of sensitive electronic equipment.

MOVs are the most commonly used technology for the protection of AC power circuits. The surge current rating of an MOV is related to the cross-sectional area and its composition. In general, the larger the cross-sectional area, the higher the surge current rating of the device. MOVs generally are of round or rectangular geometry but come in a plethora of standard dimensions ranging from 7 mm (0.28 inch) to 80 mm (3.15 inch). The surge current ratings of these surge protective components vary widely and are dependent on the manufacturer. By connecting the MOVs in a parallel array, a surge current value could be calculated by simply adding the surge current ratings of the individual MOVs together to obtain the surge current rating of the array. In doing so, consideration should be given to coordination of the operating characteristics of the MOVs selected. There are many hypotheses on what component, what topology, and the deployment of specific technology produces the best surge protective device OEM for diverting surge current. Instead of presenting all of the options, it is best that the discussion of surge current rating, Nominal Discharge Current Rating, or surge current capabilities revolve around performance test data. Regardless of the components used in the design, or the specific mechanical structure deployed, what matters is that the surge protective device OEM has a surge current rating or Nominal Discharge Current Rating that is suitable for the application.

Typically, MOVs consist of a round or rectangular shaped body of sintered zinc oxide with suitable additives. Other types in use include tubular shapes and multilayer structures. Varistors have metal particle electrodes consisting of a silver alloy or other metal. The electrodes may have been applied to the body by screening and sintering or by other processes depending on the metal used. Varistors also often have wire or tab leads or some other type of termination that may have been soldered to the electrode. The basic conduction mechanism of MOVs results from semiconductor junctions at the boundary of the zinc oxide grains formed during a sintering process. The varistor may be considered a multi-junction device with many grains acting in series-parallel combination between the terminals. A schematic cross-sectional view of a typical varistor. Varistors have the property of maintaining a relatively small voltage change across their terminals while the surge current flowing through them varies over several decades of magnitude. This nonlinear action allows them to divert the current of a surge when connected in shunt across the line and limit the voltage across the line to values that protect the equipment connected to that line.

Firstly, locate the surge protective device OEM as close as possible to the panel to be protected. Secondly, drill and punch a hole within the surge protective device OEM housing in an exceedingly position to attenuate the length of the connecting wires from the lugs of the surge protective device OEM to the circuit breaker within the adjacent panel (or fused disconnect lugs). Further, where possible, use a close-nippled connection with wires going on to the first breaker at the top of a panel. Using a close-nippled link with wires going on to the first breaker at the top of a panel ensures optimum protection of all loads connected to the panel.

Use stranded wire or larger (widely available and straightforward installation) to connect the surge protective device OEM and the breaker panel. Avoid sharp bends and excess length within the wiring. Neat installations are not necessarily the foremost effective ones. Short, direct connections are best. Finally, connect the surge protective device OEM through an appropriately rated circuit breaker, not into the main lugs of the panel. The electrician should use a fused disconnect switch to connect the lines and facilitate surge protective device OEM servicing where circuit breakers are unavailable or impractical.