ELK-930 — Doorbell & Telephone Ring Detector Instructions

Instruction manual for the ELK-930 Doorbell & Telephone Ring Detector — a compact, dual-function sensor that produces an open-collector output when a doorbell is pressed or a telephone line rings, for triggering an automation controller input, relay, or timer.

Application

The ELK-930 performs three functions. It detects ring activation from one or two doorbell pushbuttons and a single telephone line. It isolates the voltage and current from either source and produces an open collector (pull-to-ground) output that can be used to trigger an automation controller, relay, or timer. The board is pre-scored so the individual detectors can be snapped off (separated) from each other if only one function is needed.

Features

Doorbell

• Detects doorbell activation current
• Inputs for two separate pushbutton locations (front door, back door)
• No interference with lighted pushbuttons
• Produces an open collector output
• Powered by the doorbell transformer

Telephone

• Detects telephone ringing voltage
• Provides an open collector output that follows the ringing pattern

Specifications

Installation — Doorbell Detector

The ELK-930 doorbell detector monitors the current draw of a doorbell and produces an open collector output when the pushbutton is pressed and the doorbell draws 900mA or more. This open collector output can be used to trigger an automation controller input that utilizes high-to-low switching (pull to ground) for activation. There are two installation methods:

Method 1 — Single Detector, Shared Front/Back

Requires only 1 ELK-930 doorbell detector and free access to the wires leading from the doorbell transformer. This method activates when the doorbell rings, regardless of whether it's the front or back door pushbutton.

1. Mount the ELK-930 at any convenient location along the path of the two wires leading from the transformer to the doorbell.
2. Cut one of the two transformer wires. Strip the ends and place one under each of the doorbell detector INPUT terminals.
3. Run a two-conductor wire from the doorbell detector output terminals to the automation controller or device to be activated.
4. Connect one wire from the "NEG" terminal to a common NEG terminal of the controller. Connect the other wire from the "OUT" terminal to one of the input zones on the controller.

Method 2 — Dual Detector, Distinguishes Front/Back Door

Requires both ELK-930 doorbell detectors and free access to both pushbutton wires. Detector A activates on the front door pushbutton; Detector B activates on the back door pushbutton.

1. Mount the ELK-930 units near the automation equipment.
2. Run a four-conductor wire to the doorbell location.
3. Connect one pair of the four-conductor wire to the INPUT terminals on Detector A and the other pair to the INPUT terminals on Detector B. At the doorbell location, splice one pair in series between the front door wire and the transformer common, and the other pair between the back door wire and the transformer common.
4. For each doorbell detector, connect one wire from the "NEG" terminal to a common NEG terminal of the controller, and the other wire from the "OUT" terminal to one of the input zones on the controller.

Installation — Telephone Ring Detector

The ELK-930 telephone ring detector monitors the voltage on the telephone line and produces an open collector output (pull to ground) when the telephone ringing voltage is approximately 50 Volts or greater. The output follows the ringing pattern, so it can be used to trigger a controller input in sync with each ring. Connect the "R" (Ring) and "T" (Tip) terminals to a telephone Demark block ahead of the house phones, and wire the "OUT" and "NEG" terminals to the automation controller's input and negative terminals, respectively.

Warranty

Lifetime Limited Warranty — call ELK Products for details.