The Yale DCR 502 operates on a hydraulic rack & pinion principle, a proven mechanism for controlled door closure. Within the die-cast aluminium body, a precisely machined piston (rack) engages with a gear (pinion) connected to the closer's arm. As the door opens, hydraulic fluid is compressed, storing energy. Upon release, this stored energy forces the fluid back, causing the piston to return and the arm to pull the door shut. The critical aspect of this system is the integration of adjustable hydraulic valves. The DCR 502 features independent valves for controlling the closing speed (from the maximum open angle to approximately 15 degrees from closed) and the latching speed (the final 15 degrees of travel). This allows for precise calibration, ensuring the door closes smoothly without slamming and latches securely into the frame.
Compliance with **EN 1154** is a cornerstone of the DCR 502's engineering. This European standard specifies the performance requirements and test methods for controlled door closing devices. For the DCR 502, its EN Size 2 classification indicates its suitability for doors up to 45kg and 850mm width, ensuring optimal closing force for this range. Adherence to EN 1154 signifies the closer has undergone rigorous testing for durability, efficiency, and safety, affirming its mechanical integrity and consistent operational performance. The **500,000 cycle test rating** directly correlates with the EN 1154 durability test, validating the closer's long-term reliability under continuous use conditions, a crucial metric for high-traffic applications.
The DCR 502's design explicitly omits back-check, hold-open, and delayed action functionalities. This simplification streamlines its mechanical design, focusing on core adjustable closing and latching speed control. It is important to note that the DCR 502 is **not fire-rated**. Therefore, its application must be strictly limited to non-fire-door assemblies. The use of aluminium die-cast for the body ensures a balance of strength, corrosion resistance, and a relatively lightweight profile, contributing to its overall durability and ease of installation. The non-handed design minimizes inventory requirements and installation complexity, making it a versatile solution for general-purpose door control where fundamental, reliable operation and EN 1154 compliance are paramount.
