Overview
Sur-Gard SYSTEM III/IV POTS, dual-POTS, and network line cards expand central-station receiver capacity.
Product type
Module / accessory
At a glance
| Detail | Value |
|---|---|
| Category | Module / accessory |
| Primary manual | Sur-Gard Line Card Installation Manual |
| Install scope | Central station / infrastructure |
| Supervision | Central-station receiver |
What this device does in the system
Extends panel capacity (zones, outputs, wireless, power, or reporting) — plan bus address, current draw, and device limits before install.
Before you install or replace one
- Confirm exact model number on the label matches the install manual.
- Verify host panel or system family — Keybus, Corbus, Combus, PowerG, MX, or 433 MHz are not interchangeable.
- Check device limits on the panel/receiver before adding zones, sirens, or credentials.
- Include current draw in power budget calculations for modules, receivers, and keypads.
- For wireless: test RF at the mounted location, not only on the bench.
Official sources
- Product page: DSC Network Line Card For SYSTEM III (ID 144)
- Sur-Gard Line Card Installation Manual — DSC official documentation
Compatible Peripherals
This product is central-station or infrastructure equipment — it does not mount on end-user intrusion panels like a zone expander.
Host compatibility
| Host system | How it connects |
|---|---|
| Sur-Gard SYSTEM III receiver | Line card slot installation |
| Sur-Gard SYSTEM IV receiver | Network or POTS line card per manual |
Not compatible / common mistakes
Cross-family substitution without manual verification.
Replacement guidance
- Match model, frequency, and bus type to the removed device.
- Re-enroll wireless devices after replacement — ESN/serial changes with new hardware.
- Document zone/siren/device number for monitoring station handoff.
Source: Sur-Gard Line Card Installation Manual (DSC official documentation).