There are several situations that call for users to secure their power connections. This is especially so in applications that are deemed mission critical—data centers, hospitals, and military applications come to mind—where the ability to secure the connection between your device and its power source can mean the difference between being online, or completely cut off. This can be the difference between an application or mission succeeding or failing, and sometimes even life or death. 

Locking Cords versus Zip Ties

At this point in the evolution of locking power cords, the universal method for securing a connection is via the cord itself. Sleeves, holders, and zip ties have commonly been used to address the problem of connectors becoming unseated. Like many early solutions, they got the job done, but with some downsides: namely, the inability to easily make moves, adds, and changes. Ever try removing a zip tie from a C14 in a rack full 1U servers? Exactly.

Assessing Your Locking Needs

It would be easy to assume that a locking cord is a locking cord, but there are a number of solutions available, and all are dependent on your situation and the application(s) you are working with. Considerations include the brand and type of your PDU or power supply, and whether you need to secure one or both sides of the cord.

Choosing the Right Locking Cord

Locking cord manufacturers typically use a single-letter designation to differentiate one cord type from another. While this common nomenclature is helpful, one might forget the difference between a Z-Lock and an A-Lock when it is time to make your selection. Here are some tips to help you remember the cord types and make the best choice:

Do you have a proprietary power solution? If so, then you need a P-Lock or a W-Lock. To remember this, think: The Proprietary Way. But which will best suit your needs, P or W? It all depends on the manufacturer of the PDU you are plugging into:

  • Use a P-Lock if you have ServerTech, Raritan, Vertiv, Knurr, or NextGen Eaton equipment.
  • Use a W-Lock if you have Schneider/APC, Panduit, Enlogic, or NextGen HP power gear.

Do you prefer a universal power solution? If you need a cord that will fit any number of situations or manufacturers, then you are looking at either an A-Lock or a Z-LOCK. Think: From A to Z. But how do you decide between the two?

  • Use an A-Lock if you are looking to lock only the female end of the cord.
  • Use a Z-LOCK if you are looking to lock both ends of the cord.

These two steps should help you to make the best locking cord choice. Just remember: first narrow the field by choosing between a proprietary or universal solution, then zero in on your choice by determining if you want to secure one end or both ends of your power connection.


When it comes to locking cords, StayOnline is your one source for the getting the right cords to meet your needs. When it comes to securing your power connection, there is more to locking power cords than meets the eye. For all your power cable needs, don't hesitate to contact our team at StayOnline today. For more information, reach us by phone at 888/346-4688 or by email at