Uncovering the Mystery of Voltage Sags

Every manufacturing facility has seen it happen: The need to reset equipment for no reason. Nothing died and no components failed. What happened?

The answer: voltage sags. Because so few people understand what voltage sags are or the problems they cause, most assume they’re not happening. But the Electric Power Research Institute says that nearly 70% of industrial facilities experience voltage sags. Based on the experiences of our customers, we believe that number is closer to 90%.

How Voltage Sags Impact You

Voltage sags are nearly undetectable. The interruptions they cause are too short and shallow to notice.

Every time voltage sags, equipment has to be reset and hours of productivity are lost. (Depending on the line, you may also need to disassemble, re-clean and re-sterilize, etc.) Downtime can lead to bigger issues, too. If you miss a ship date, for example, your customer may look elsewhere to backfill. During this process, they could discover the same product and service for less and make a switch.

Identifying the Causes of Voltage Sags

Without monitoring, it’s difficult to pinpoint causes. Many situations can create voltage sags:

• A car accident that downs a utility pole
• Bad weather
• Local utility problems
• Loose/defective wiring
• Squirrels or other animals

Depending on the source, voltage sags may occur more often during certain times. (In the winter, for example, when birds nest in service entrances to keep warm.)

Just like the precautions you take to prevent lightning strikes, there are also ways to prevent voltage sags. As a Rockwell Automation partner, Van Meter can help you manage mystery trips:

• Voltage monitoring provides instant event notification, documenting sources of disruptive power events. As voltage is monitored, information about your incoming power quality is transmitted to a database where it’s analyzed and sent to other monitoring subscribers so everyone can view data and reports. This helps pinpoint causes of mystery trips so you know how to take action.
• Voltage sag protection guards against sags and brief outages. By providing sag ride-through for up to five seconds, you’ll be covered when the next mystery trip occurs so you can keep your lines running.

If you’re experiencing mystery trips, Van Meter can identify the cause and explain ways to monitor power quality and prevent downtime. We’ll design a cost-effective solution providing support and answering questions long after it’s in place. To learn more, call us at 1-800-247-1410.

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