The Major Uses of Plastic Padlock Seals in Electric Utilities

The Major Uses of Plastic Padlock Seals in Electric Utilities

Posted by Steve Diebold

When it comes to tamper detection for electrical utility meters, padlock seals are the global standard. The meters may be sealed in a variety of ways and are available in a multitude of configurations. Sealing the meter box is a typical practice, and in some cases, the ring holding the meter in place is also sealed. The seals on certain specialty meters may be doubled. Two seals are used: one on the meter's front, which protects the electrical interface; and another on the box, which serves as a locking ring.

In the United States, plastic padlock seals are utilized in the vast majority of situations. Fortunately, American Casting & Manufacturing produces three main varieties of plastic padlock seals in addition to several variants of each. All may be personalized in terms of color and markings to suit the preferences of the user. Common categories include:

Clear Plastic Jacketed Padlock Seals

Currently, advanced padlock seals have become popular due to their improved tamper detection and performance. This is because the XPC-2 is protected by a transparent acrylic case that can endure rough use and keep information safe. There is also an XPC model, the XPC-BC, with a very visible bar code.

Jacketed seals make tampering easily detectable since they cannot be opened by force without breaking the seal or damaging the transparent cover. This method is quickly gaining favor for usage on meters that are read by centralized (AMI) or remote readers. A more advanced seal with better protection from detoriation helps keep the seals in place to prevent tampering and make sure the meter is still readable for longer periods of time between inspections, which happen less often now that smart meters are becoming more common.

Plastic Padlock Seals

Plastic security seals are utilized in meters when the opening is tiny or the seal can be allowed to break away effortlessly. The AC&M type 7001 Fast Seal is the go-to all-plastic seal for electric metering applications. This fast seal can be used in numerous utilities, which has earned the nickname "demand" seal because of its frequent use on demand meters. Commonly, demand meters need a new seal once a month or at regular intervals.

A Fast seal can be applied and withdrawn using just one hand, making it ideal for use when a meter technician has only one free hand available to do a seal change. Although demand meters are losing relevance, there are still utilities that require a seal that can be applied and removed with a single hand. When compared to more durable seals, those made entirely of plastic may be simpler to spot as having been tampered with due to their design. Having fewer moving parts to examine makes the user have an easier time finding flaws like cracks and dings.

Wire Padlock Seals

The AC&M type 8001 plastic and solid wire padlock seal is widely used on single-phase and residential meters. This seal was the first and is still the most popular for usage on electric meters in the 1960s. Depending on the design, wire hasps can either need cutting to open or have breaking notches (scoring) that allow for tool-free removal.

In the past, padlock seals and other similar seals were constructed entirely of steel. Some utilities continue to employ the original, all-steel design because it provides the strength and longevity they require.

Additional Usage Beyond the Meters

Plastic padlock seals can be used to keep out intruders and protect valuable utility equipment like control and switch boxes. They can also be used as lockout labels for transmission connections, junctions, and other switching applications. Line trucks, transformer labeling, tool boxes, and many other places where openings and closings need to be managed might benefit from this seal as well.

Padlock seals have widespread application in fields as diverse as the medical, finance, food, and airline industries, among others. Many other kinds of seals are also used by utilities for various purposes. You may find these and more elsewhere on's website and blog. Additionally, this topic will be explored in upcoming narratives.

Over the past century, we have taken great pride in serving as a reliable and trusted resource for utilities of all sizes around the globe. Equally noteworthy is the fact that we have been a market leader in the production of seals of all kinds for over a century, and that we have done so out of facilities that we have owned and operated in the United States the whole time. Utilities continue to rely on AC&M to supply their tamper evident seal needs because of the company's unwavering commitment to reliability, speed of service, and product quality.

We're here to help if you have any inquiries regarding our seals, including smooth pull tight security seals, or about incorporating seals into your utility operations. During regular office hours, you may talk to a seasoned professional about seal application services. Get in touch with a seal expert by emailing or calling 1-866-304-4289 in the US or 516-349-7010 internationally. As an alternative, you may visit our website ( to find a sales or service location outside the United States.