Service manual

Functional Description

DCB, DCFCB and DCFCTB Models

Carrier Detect

Carrier Detect input requires a pull to ground to indicate when carrier is present.

Sensors and Sensor Inputs

The DCFCB and DCFCTB comes with the following inputs to work with external

sensors and 2 built-in sensors to report the following conditions:

JP22

AC (External Sensor Input)

JP10-1

Low Battery, 12 VDC

JP5-11

Low Battery, 48 VDC

JP5-9 (only used with 48 V type

sirens.)

Rotation (Proximity Switch)

JP5-7

Rotation (Current Sensor)

JP10-3

Main Siren Motor Current

JP5-5

Intrusion

JP5-3

AC Sensor (built-in)

During normal operation (when AC is present) the built-in AC sensor does not light.

If AC is lost, the AC LED lights. The AC sensing logic is dependent on both the

built-in AC sense and the external AC sense points. If an AC loss is detected at either

point, a report is sent. A loss of AC is not reported immediately. The controller

makes sure the loss lasts at least 2 seconds then it adds (1 second * Site #) before

reporting. Each siren with an AC failure reports by site number in sequential order

with a two second delay between sites. Once AC is restored, another automatic report

is sent in the same order to show change of state. If AC is restored before the

automatic report is sent, the report is cancelled.

Low Battery Sensor (built-in)

The low battery sensor input measures the voltage across the four (4) series batteries.

If the battery voltage goes below ~40 V for 20 seconds, the controller reports a low

battery condition. The controller does not automatically report when the battery

voltage returns to normal to eliminate the possibility of multiple reports when a

battery is very weak. The low battery condition remains latched in memory until the

controller is reset or a function is run and the battery voltage is restored.

Digital Inputs for Rotation Sensor

Two rotation sensor inputs exist. Depending on the sensor option purchased, either

the current sensor or proximity switch input is used.

 Standard Rotation Sensor Input: JP10-3 is used for the rotation motor current

sensor. This input latches when current is detected. During a siren rotation this

input is pulled low. The latch is reset by the RESET command.