Prevent Power Surges with Full Spectrum Surge Protection
A voltage spike is a momentary extreme burst of electricity in an electrical circuit. This energy spike may be short-lived, but could still be enough to seriously damage the electronics. Although voltage spikes are brief events that rarely last more than a few microseconds, all it takes is one snowball to set off an avalanche.
In complex systems, even seemingly small events can have serious consequences. This is definitely true for industrial automation systems, in which many different devices need to work together in order to maintain normal operations. Computers and communications equipment are essential components of many modern automation systems; however, they are also particularly susceptible to power surges from voltage and current spikes. In these systems, serial device servers are key communication gateways that connect the broader Ethernet network with specific serial devices. A power surge that damages this vital communications link will bring the entire process to a halt.
What Causes Power Surges?
There are many potential sources of power surges. Two of the most common are lightning and switching surge:
Lightning
Lightning creates substantial electric discharge at the location it strikes. Lightning that directly strikes a building can clearly endanger its electrical system, but there are other ways for lightning strikes to cause power surges. For example, when lightning strikes a power transmission line, the effects can cause equally dangerous voltage spikes miles away.
Figure 1: Lightning strikes can cause current levels to reach 20-150 kA
Lightning is an ever-present threat to sensitive electronic systems. At this very moment there are 2000 lightning storms in progress, and there is an average of 5000 lightning storms a day. Of course, lightning strikes are more common in some regions than others. Nevertheless, lightning poses a significant risk and its consequences must be mitigated.
Figure 2: Distribution of lightning strikes worldwide
Source: NASA
Switching Surge
There are many malfunctions in electrical equipment that can lead to power surges. Tripped circuit breakers, short circuits, or even power transitions can all create switching surges. These electrical irregularities may be man-made but can cause just as much damage as lightning. A large power substation that regularly cycles on and off generates enough switching surges to threaten sensitive electronic devices.
Why Surge Protection Is a Necessity, Not an Option
Industrial automation operators generally understand that power surges pose a serious threat to their systems and take steps to reduce this threat. Not only do power surges damage and destroy equipment, they cause costly interruptions. In the case of serial-to-Ethernet communications, irreplaceable historical data could be lost if the serial or Ethernet ports suffer a power surge.
Substation automation facilities are at a particular risk for power surges because they are highly susceptible to both of the major sources of voltage spikes. As outdoor facilities, substations are more vulnerable to lightning strikes. As electric facilities that perform electric transformation and switching, switching surges are also a danger. In addition, electrical substations require reliable serial communications in order to perform essential tasks such as reading power meters. If surge damage occurs on a serial line, then any meter data on the associated line will be lost. This combination of increased risk profile and greater consequences means that robust products with industry-certified surge protection are a must for electrical substations.
For a serial device server, there are three major points of weakness that could be damaged by a power surge: the serial line, the Ethernet line, and the power line. Acknowledging this threat, many serial device servers offer surge protection on the Ethernet and power lines. However, most serial device servers leave the serial line unprotected. As a consequence, the serial line is often the weak link in serial device server surge protection.
Full Spectrum Surge Protection
Surge protection is not an option for vulnerable communications links. Effective and comprehensive surge protection reduces downtime and increases system stability by eliminating the most common cause of failure. IEC 61000-4-5 testing is imperative to verify that a device has sufficient surge protection to withstand voltage spikes. IEC 61000-4-5 Level 1 testing is intended for a device that operates in partly protected electrical environments, while IEC 61000-4-5 Level 2 and higher testing certifies that a device can operate in highly electrical environments.
| |
Description |
Certification |
| Class 1 |
Partly protected electrical environment |
IEC 61000-4-5 Level 1 |
| Class 2 |
Electrical environment with well-separated cables |
IEC 61000-4-5 Level 2 |
| Class 3 |
Electrical environment with parallel cables |
IEC 61000-4-5 Level 3 |
Many manufacturers offer serial device servers with IEC 61000-4-5 rated surge protection on the power and Ethernet line. However, the same level of integrated surge protection is rare for the serial line. In order to acquire serial line surge protection, device servers are often deployed with additional after-market external surge protection devices. However, this retrofit adds complexity, increases space requirements, imposes additional maintenance costs, and complicates support cases. Industrial automation systems can be complicated enough without an additional requirement to deploy, maintain, and support yet another device just to provide serial line surge protection.
Moxa's NPort® A Series: Closing the Gaps in Surge Protection
Moxa's NPort® A series of serial device servers sets itself apart from other solutions with built-in IEC 61000-4-5 rated surge protection on the serial line in addition to Ethernet and power line surge protection. IEC 61000-4-5 rated surge protection certifies that a device can operate in highly electrical environments to offer a reliable, resilient serial device server solution. The NPort® A series is a convenient all-in-one package, and with built-in serial line protection, it is no longer necessary to find, test, and deploy an external serial surge protection product.
To discover the secrets behind how the compact NPort® A series device server's built-in IEC 61000-4-5 certified surge protection provides the most reliable serial-to-Ethernet communications visit http://www.moxa.com/event/tech/2010/NPort_A_series/surge.htm.
For more on the NPort® A series visit: http://www.moxa.com/Event/Tech/2010/NPort_A_Series/index.htm.
Key Features of Moxa's NPort® A Series
NPort® 5000A series:
1 and 2-port serial device servers
• The world's lowest power consumption—just 1 W
• Quick and easy 3-step web-based configuration
• Surge protection for serial, Ethernet, and power lines
• COM port grouping and UDP multicast applications
• Screw-type connectors for secure installation
• Standard TCP/IP interface and versatile TCP and UDP operation modes
NPort® IA5000A series:
1, 2, 4-port serial device servers for industrial automation
• Enhanced surge protection for serial, Ethernet, and power line
• 2 KV isolation for serial signals
• Rugged screw-type terminal blocks for power and serial connectors
• C1D2 and ATEX certified for harsh industrial environments
• Cascading Ethernet ports for easy wiring
• Redundant DC power inputs
• Warning by relay output and email
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