What is the maximum number of devices on the 6820 SLC loop, and how do I expand capacity with a 6815 SLC expander?

The 6820 built-in SLC loop supports up to 159 System Sensor (SK) detectors and 159 SK modules, or 127 Hochiki (SD) protocol devices (Page 1) [10].

The system can be expanded to a maximum of 1,110 SK points or 635 SD points (Page 1) [16].

Each 6815 SLC expander adds 159 SK sensors and 159 SK modules, though it only supports SK protocol devices (Page 12) [6].

To expand capacity with a 6815:

1. Ensure power is removed from the control panel (Page 42) [1].

2. Mount the 6815 in the 6820 cabinet, 5895XL cabinet, or 5815RMK remote mounting kit (Page 42) [1].

3. Connect the 6815 to the FACP via the SBUS (Page 42) [1].

4. Use the onboard DIP switches to select a unique SBUS ID# (Page 42) [1].

5. Add the module to the system using JumpStart or manual programming (Page 42) [1].

6. Connect the SLC devices to the 6815 loop terminals (Page 42) [1].