Technical glossary

Explanation of various characteristics and abbreviations.

PC size (A, see picture)
The distance between the center of the crank and the center of the cylinder.

Backset (B, see picture)
The distance between the front of the faceplate and the center of the cylinder.

Bolt length (C, see picture)
The total distance from the end of the latch bolt to the front of the striker plate.

Cylinder operation (D, see picture) 
The bolt is provided with a recess and mechanism for placement and operation of a key cylinder.

Key cylinder type designation. The diameter seen from the front is 17mm.

Key cylinder type designation. The diameter seen from the front is 22mm.

Fail Secure
Locked without voltage.

Fail Safe
Unpowered unlocked.

By using operating and quiescent current principles, it is possible to anticipate the question “what should happen in the event of a power failure?”. In a highly secured situation, an open door should be self-locking in the event of a power failure. In, for example, a device, a door should unlock correctly in the event of a power failure. This is often less easy to achieve in the case of motor-driven locks.

Puls unlock
With pulse release, the electric door opener remains open (continuously) until the door is pulled open and closed again. One pulse is enough. The other door openers (operating current/quiescent current) must be released each time.

Revolving Door
A door that can open both ways.

Such a door can be provided with an electric door latch, provided it is provided with a properly functioning hydraulic floor spring or frame sill spring.

Escape doors
Doors that can be opened independently (ie without outside help) in the event of a calamity. This can be done mechanically (door handle, panic bar, etc.), or an electrical door lock operating on the quiescent current principle, whereby an emergency disconnect switch is placed directly in the supply line from the transformer to the locking coil. The color of this interrupt switch can be blue (eviction) or green (included in the escape route).

Resistance to lateral pressure
The opener can withstand at least a sideways applied static pressure on the bolt catch as specified.

Side preload
Lateral pressure built up in the locked condition caused by architectural imperfections, such as door warping or hanging, incorrect positioning, retrofitted draft rubbers and the like, or lateral pressure caused by users before the opening impulse is given. Very important point for emergency exit doors and highly frequently used doors.

Standard class
The openers in this category are intended as disciplinary protection. In a test environment they can withstand a static lateral pressure of 5,000N on the bolt catch. In practice, the ideal correct installation is not realized, the lock case of the opener is not or hardly supported, resulting in a resistance of 1,000 to 1,500N.