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What Is Sliding Security Door Interlock?

When ordering a sliding security door from Seconline it is important to recognise whether you have receiving interlocks on your existing glass fixed door panels. Before we go any further it would be important to gain a definition of the words interlock.

The following definition is from Interlock;

  1. To fit into each other as parts of machinery, so that all action is synchronised.

  2. To interweave or interlace, one with another.

  3. To lock with a one another.

  4. To fit (parts) together to ensure coordinated action.

In other words or simpler terms, interlocking simply means that one moving part will lock in to another stationary or moving part to so as to lock, join and link your sliding security door and your fixed glass panel. Most modern extrusions for sliding glass door systems now will have receiving interlocks as part of the fixed glass panel, however, not always.

This then raises the question what is to be done if there are no receiving interlocks? There are two possible options:

  1. Install offset interlocks to the fixed glass panel. (Individual advice can be obtained Re: the installation of receiving interlocks by contacting us direct, either via email or phoning 1300 735 405 and talking with our support team.)

  2. Change order from the seconline factory from frame interlock which is a standard inclusion to a side bug seal.

If however a decision is made that there is no receiving interlock is required for your security screen door and that the need for security is minimal, then a side bug seal can be ordered to replace the frame interlock and this will incur no extra cost. This is a decision that needs to be made at the point of order.  The factory must be notified of this decision so as to modify your order.

Using the frame interlock to connect with a receiving interlock is obviously a more secure option as it will lock the door on the opposite side to the lock. This then will mean that not only is the door locked into the locking mechanism on the lock side, it will also lock the door on the opposite side simultaneously as the door is slid into the locking position.

It is very important when ordering Centre Opening Sliding French style doors to have receiving interlocks, as this locates the doors in the centre locking position. If no receiving interlocks are on the fixed glass panels then the frame interlock has nowhere to lock into and is allowed to travel past the glass fixed panel pushing the opposite door with it. The two doors will lock together in the middle, however, there is nothing to lock them on either end in the central centre position. This is not a good outcome and given that the widths of sliding centre opening French style doors will be greater than a single sliding security door, then this will increase the need to have the two doors locked into the fixed glass panel at either end.

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