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Silent Knight
6820
Sbus Class A Supervision Lost

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When diagnosing codes, always check the event history log first. Many trouble conditions are intermittent and tied to environmental factors like temperature or moisture.

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SBUS Class A supervision lost: SK-6820 Trouble Code | Fire Alarm Resource Center

SBUS Class A supervision lost

trouble

Silent Knight SK-6820

67 views·0 field notes

What This Code Means

The panel has lost the return path for a Class A SBUS circuit.

Common Causes

1Break in the SBUS wiring
2Loose connection at the last device

Resolution Steps

Trace the SBUS wiring to find the break, check connections at all SBUS devices, and restore the loop continuity.

Manual References(3)

1silent knight6820Datasheet2018Open

2silent knight6820/6820EVSInstallation2022p. 139, 148, 140, 142, 141Open

3silent knight6820EVSDatasheet2020Open

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Related Codes

Printer is out of paper troubleThe system printer has run out of paper.DISABLEA point or circuit has been manually taken out of service, which prevents the activation of notification appliances or alarm initiation from that specific device.GROUND FAULTAn earth ground fault occurs when the panel senses an unexpected flow of current from one or more of its terminals to the earth connection (Terminal 2).Calibration trouble alertA sensor has failed its internal calibration test.MissingA device or module (such as an SLC device or a 5496, 6815, or 5815XL module) is physically connected to the system but is not being recognized by the panel.

Related Questions

How do I program the Silent Knight 6820 via the USB interface, and what software is required?What is the maximum number of devices on the 6820 SLC loop, and how do I expand capacity with a 6815 SLC expander?How do I program zone assignments and custom zone labels on the Silent Knight 6820?

All SK-6820 trouble codes SK-6820 panel page