This page covers the device-specific wiring for a System Sensor 2012J or 4WTAR-B wired smoke detector. For general device setup and settings, see Add a device.
The wired smoke detector triggers a BRNKL alert when smoke is detected, even when no one is aboard. Useful for early fire detection in the engine room, salon, or any enclosed space.
Uses a digital input slot (4–7) on the BRNKL connector.
For BRNKL Blue wiring, see Add wired smoke detector. Wiring differs between the two systems — the relay common connects to ground on the BRNKL 5G, not to +DC as on BRNKL Blue.
Prerequisites
-
System Sensor 2012J or 4WTAR-B smoke detector
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12–24 V DC unswitched power supply (fused)
-
Marine-grade wiring if extending the supplied leads
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An available BRNKL digital input (slot 4, 5, 6, or 7)
Disconnect shore power and turn off the main DC breaker before working on the BRNKL connector.
Wiring
Both detectors use a relay output that closes when smoke is detected. The relay common (C) connects to ground — when smoke is detected, the relay closes and pulls the BRNKL input to ground, triggering an alert.
System Sensor 4WTAR-B
|
Terminal |
Function |
Connects to |
|---|---|---|
|
(1) + IN |
DC power |
+12/24 V DC (fused) |
|
(3) − IN/OUT |
Ground |
Common ground |
|
(7) C |
Relay common |
Common ground |
|
(8) NO |
Relay normally open |
BRNKL connector — slot 4, 5, 6, or 7 |
System Sensor 2012J
|
Terminal |
Function |
Connects to |
|---|---|---|
|
+ (Power) |
DC power |
+12/24 V DC (fused) |
|
− (Power) |
Ground |
Common ground |
|
C (Relay) |
Relay common |
Common ground |
|
NO (Relay) |
Relay normally open |
BRNKL connector — slot 4, 5, 6, or 7 |
Note which slot you use — you will need it when configuring.
Install the detector
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Mount on the ceiling or high on a wall in an enclosed space where smoke accumulates quickly.
-
Follow the manufacturer's placement guidelines for the specific model.
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Use a fused DC power supply sharing the same ground reference as the BRNKL 5G.
Configure
In the BRNKL app, go to Settings > Devices and select the input matching your slot:
|
Slot |
App setting |
|---|---|
|
4 |
Digital 1 |
|
5 |
Digital 2 |
|
6 |
Digital 3 |
|
7 |
Digital 4 |
This is a Digital input. Recommended settings:
-
Monitor — on
-
Alert — on
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Name — e.g., Smoke detector
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High Name — Alarm
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Low Name — Clear
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Alert When — High (alerts when smoke is detected)
Consider enabling alerts so notifications are sent even when BRNKL is disarmed — a smoke alarm is always worth knowing about immediately.
Tap Save.
Test
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Wait 15 minutes for settings to sync.
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Confirm the dashboard shows Clear with no smoke present.
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Use a smoke detector test spray (or briefly hold a smouldering match nearby) to trigger the alarm. The dashboard should switch to Alarm and send an alert.
-
Ventilate the area and confirm the detector resets to Clear.
Test the detector regularly to verify proper operation. The 4WTAR-B supports interconnect wiring for up to 12 smoke alarms — when one triggers, all connected alarms sound. See the System Sensor installation manual for details.
Troubleshooting
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Dashboard shows Alarm with no smoke present — check for steam, dust, or exhaust near the detector. Relocate if the installation environment causes false triggers.
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Detector doesn't trigger dashboard — verify relay common (C) is wired to ground (not +DC), the NO terminal goes to the correct BRNKL slot, and the correct Digital input is enabled in the app.