How to add a door in Lenel OnGuard

LP1502 controller, MR52 interface, OSDP readers, REX and strike. Values come from your wiring diagram.

The steps are the same in 7.x and 8.x. 8.3 adds Mercury M-Series and IP client connections. Fields marked Verify in your version were not confirmed in public docs.

1. Add the access panel Flag

System Administration › Access Control › Access Panels

Pick the panel type for the controller, click Add, then fill the Location tab. Lenel names Mercury boards with LNL part numbers: LP1502 = LNL-X2220, EP1502 = LNL-2220.

Field	Set to
Panel type	LNL-X2220 (Mercury LP1502)
Name	Lobby controller
Online	Checked
Primary connection	IP address of the LP1502
Downstream port baud	38,400 (match the MR52 switches)	Verify in your version

2. Add Reader 1 on the MR52 Flag

Access Control › Readers and Doors › Add

In OnGuard the MR52 is not its own object. It is the reader Type LNL-1320. Both readers share one address and differ by Reader Number.

Field	Set to
Name	Lobby — Entry
Panel	Lobby controller
Type	LNL-1320 (Dual Interface) = MR52
Port / Address / Reader Number	Port 2 · Address 0 · Reader 1
Output	OSDP	Verify in your version
Card format	Site format, for example 26-bit

3. Set OSDP, keypad and door timing Flag

Readers and Doors › reader settings

Turn on Secure Channel only if the reader is set for it. Strike time and held-open time are in seconds.

Field	Set to
OSDP address	0
Secure Channel	Off for the first test, then On	Verify in your version
Keypad	None when the reader has no keypad
Strike time	5 s
Strike mode	Fail-secure

4. Add Reader 2 Flag

Readers and Doors › Add

Same MR52 address, Reader Number 2. Pair it with Reader 1 so both readers control one door.

Field	Set to
Name	Lobby — Exit
Port / Address / Reader Number	Port 2 · Address 0 · Reader 2
OSDP address	0
Paired reader	Paired with Reader 1	Verify in your version

5. Check door contact, REX and strike Flag

Readers and Doors › inputs and outputs

Map the door contact, REX and strike to the terminals in the diagram.

Field	Set to
Door contact	MR52 input · NC
REX	MR52 input
Strike relay	MR52 relay · fail-secure

6. Timezone and access level Flag

Access Control › Timezones, then Access Levels

Make or reuse a timezone, then an access level that includes the new readers. Assign it to a test badge.

Field	Set to
Timezone	Always, or business hours
Access level	Lobby — All hours
Readers in the level	Entry and exit readers

7. Download and test in Alarm Monitoring Flag

Alarm Monitoring › System Status

Download the panel, then use Open Door(s) to fire the strike. Present a badge, press the REX, and hold the door past the held-open time.

Field	Set to
Expect	Access granted on the readers
Expect	REX releases the strike

Your door

Open the diagram builder, wire the door, then use Program it. Bound fields pick up addresses, protocol and fail mode.

Edit in builder Default codes

Checklist

MR52 DIP address matches the Address field
MR52 baud matches the panel downstream port
OSDP termination is on the last device
Reader protocol matches the diagram
Card format matches the badges
Panel downloaded after the changes
Grant, REX, forced and held were tested

Common errors

Reader offline: address or baud mismatch, or RS-485 polarity swapped.
Panel won't connect: Mercury-branded LP1502/MR52 boards are blocked by the license OEM mask. OnGuard expects LNL-branded boards.
Card reads, access denied: wrong card format, or the level is not on the badge.
Door Forced on every exit: REX not mapped, or the REX contact is the wrong NO/NC.
OSDP reader blinks and does not read: Secure Channel is on in OnGuard but not on the reader.

Sources

OnGuard System Administration User Guide · LenelS2 partner portal
Alarm Monitoring user guide · LenelS2
Mercury to Lenel model chart · Genetec TechDocs

Questions

How do you add an MR52 in OnGuard?

The MR52 is the reader Type LNL-1320 on Readers and Doors, not a separate device. LP1502 is LNL-X2220 and EP1502 is LNL-2220.

Why will a Mercury-branded board not come online?

Mercury-branded boards can be blocked by the OnGuard license OEM mask. OnGuard expects LNL-branded boards.

Planning aid only. Values are typical and vary by manufacturer, code edition and jurisdiction. Verify with manufacturer data, NEC/NFPA/TIA and the local AHJ. HireLV is not liable for designs based on these tools.