Product Specification Sheet APS466

Rev. 07/2013

RY502A Universal Dual Door Timer relay

Architects' And Engineers' Specifications

The Universal Dual Timer Relay(s) shall be Alpha Communications® RY502A or equivalent. Once the RY502A is activated by an input of 8 to 24VAC, (typically from a door opener output of an intercom or video-intercom system), the RY502A will first send 16VAC (and activate a 'Form C' relay) for the outer door for a programmed period of time. The RY502A will then automatically switch the voltage and 'Form C' relay to the inner door opener or mag lock, also for a programmed period of time. delay times shall be programmable by means of two (2) separate timer controls. RY502A shall allow for an optional 'man trap' capability, whereas the 2nd (inner) door will not activate until a contact is activated, indicating the 1st (outer) door is closed Relay shall surface mount right to the finished wall and shall be installed in a suitable environment that is free from excessive dirt, dust, temperature, humidity, grease and water.

All wiring to relay shall be low-voltage Class II wiring, installed as per all federal, state, and local electrical and building codes.

RY502A Universal Dual Timer Relay

The Alpha Communications® RY502A Universal Dual Timer Relays are used for a variety of applications. The primary use is for an entry intercom (or video-intercom) system, where there is an outdoor entry panel and an outer door and then an inner door which must be controlled by electric door openers or mag locks. The RY502A can be connected to a standard 8 to 24VAC electric door opener output from many intercom amplifiers to allow connection to a magnetic or different type or voltage door opener. It can also be used to provide two (2) independent 'Form C' relay contacts from virtually any 8 to 24VAC input source. The RY502A is powered directly from a standard 16VAC transformer (model SS102A or SS105B).

Once the RY502A is activated by an input of 8 to 24VAC, the RY502A will first send 16VAC (and activate a 'Form C' relay) for the outer door for a programmed period of time. The RY502A will then automatically switch the voltage and 'Form C' relay to the inner door opener or mag lock, also for a programmed period of time.

The RY502A relays are designed to easily surface mount right onto the finished wall by means of self-stick mounting tabs or by using the mounting holes provided for screw mounting.

Connections are positive screw terminal type, using a barrier type terminal connector strip.

  • Easily Installs Right on Finished Wall Surface
  • Operates on Safe Low-Voltage Class II Wiring
  • Provides Two (2) 'Form C' Type Timed Relay Outputs from a single input
  • Convenient Barrier Type Screw Terminal Connections
Dimensions: 4.25"W (108mm) x 3.20"H (82mm) x .75"D (20mm)
Relay Type: Dual 10.0 Amp (@30V) SPDT Relays with protective covers
Power Required: 16VAC, 10VA (from SS102A or SS105B transformer)
Connections: Barrier Type Screw Terminal Connectors.
Trigger Power: 8VAC to 24VAC
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Due to continuous product improvement, all colors, sizes, materials, finishes and specifications are subject to change without notice.