Overview
MAXSYS access control kits bundle PC4820 door control, PC4850 card access, readers, credentials, and related Combus modules for PC4020-based integrated intrusion + access installs. Access shares the same panel, partitions, user codes (up to 1,500), and 64 access levels as burglary—doors can be shunted, scheduled, and reported through the same communicator.
End-user benefits highlighted in DSC's MAXSYS end-user guide:
- Seamless integration — One system monitors who enters and when, tied to intrusion partitions.
- Simple operation — LCD keypads with programmable function keys; one-button arming shortcuts.
- Rugged reliability — Industry-leading lightning and static protection on MAXSYS panels.
- False alarm reduction — Panel features reduce nuisance alarms on commercial sites.
- IP reporting — T-Link TL-250/TL-300 uses existing LAN paths with AES encryption options.
Typical targets: middle-market retailers, schools, government buildings, industrial complexes, financial institutions, and high-end multi-unit residential.
At a Glance
| Component | Role |
|---|---|
| PC4020 host | Intrusion + access logic, Combus, communicator |
| PC4820 | Door control modules (up to 16 on system) |
| PC4850 | Card access control modules (up to 16) |
| User codes | 1,500 codes; assign to access levels and partitions |
| Automation | PC4401 DataLink optional for building automation tie-in |
Before You Deploy a Kit
- Confirm door count, reader type, and fail-safe vs fail-secure hardware per door.
- Plan Combus addresses for PC4820/PC4850 alongside zone and output modules.
- Program access levels, time zones, and anti-passback rules in DLS—not at the keypad alone.
- Verify fire release and unlock on AC loss requirements with local code.
Official Sources
- Product page: DSC MAXSYS Access Control Kit (ID 24)
- 30-214 MAXSYS End-user Cheat Sheet; MAXSYS 12-page brochure — DSC official documentation
- PC4020 v3.5 Installation Manual and PC4820/PC4850 module install sheets
Compatible Peripherals
Required Host
| Item | Notes |
|---|---|
| PC4020 (or PC4010) | MAXSYS panel with Combus and DLS2002+ |
| LCD4500 / LCD4501 | Programming and daily operation |
| Combus power budget | Each PC4820/PC4850 consumes bus current—plan PC4204 if needed |
Access Kit Components (typical)
| Module | Function |
|---|---|
| PC4820 | Door control (strike, contacts, REX) |
| PC4850 | Card reader interface |
| Credentials | Cards/fobs compatible with enrolled PC4850 readers |
| Readers | Models approved in PC4850 install documentation |
| T-REX / request-to-exit | Per door hardware list on product page |
Integrated Intrusion Devices
Access kits coexist on the same PC4020 with:
- PC4108A / PC4116 zone expanders
- PC4216 low-power outputs
- PC4164 wireless receivers
- T-Link TL-250/TL-300 IP communicators
- PC4401 automation interface
Not Compatible
- Standalone access panels without PC4020 host
- PowerSeries PK keypads for access programming
- Non-DSC readers not listed for PC4850 without verification
Source: MAXSYS brochure; PC4020 v3.5 Installation Manual; product page DSC MAXSYS Access Control Kit (ID 24)