SES OPTT1AMUI, MUI MODULE FOR UNITS THAT WILL NOT HAVE MODEM OR COMM OPTIONS
The SES OPTT1AMUI is the TEC1A Multi-Unit Interface option used when multiple compatible TEC1A telephone entry units need to share one telephone line. It is most often considered on properties with more than one gate, pedestrian entrance, building entrance, or access point that must communicate through the same telephone service.
SES describes the MUI option as the module for units that will not have modem or COMM options. That distinction matters because some TEC1A option packages already include MUI as part of a larger communication board package. Installing the wrong option can duplicate functionality or leave a site without the communication features it actually needs.
This is an internal TEC1A option module, not a complete entry panel. It should be matched to the unit generation and option package before ordering. The number of modules required depends on the number of TEC1A units sharing the line, since SES notes one is required for each unit placed on a single line.
Compatible With
- Select Engineered Systems TEC1A units that need Multi-Unit Interface line-sharing capability
- TEC1A units without modem or COMM option boards where MUI is required
- Multiple TEC1A telephone entry units sharing a single telephone line when each unit is equipped correctly
- T1A2L and T1A4L TEC1A models when the option package supports OPTT1AMUI
- Related to Deluxe and Premium TEC1A configurations where MUI may already be included
- Not a modem, NIC/Ethernet board, serial-only board, 2-reader board, or complete telephone entry system
Features & Specifications
| Manufacturer | Select Engineered Systems |
|---|
| Product Type | TEC1A Multi-Unit Interface module |
|---|
| Part Number | OPTT1AMUI |
|---|
| Application | Allows compatible TEC1A units to share a single telephone line |
|---|
| Compatible Series | TEC1A Series |
|---|
| Required Quantity | One required for each unit placed on a single shared line |
|---|
| Included Functions | MUI line-sharing function |
|---|
| Notes | Used where modem or COMM option package is not installed |
|---|
Also Known As / Related Part Numbers
- SES-OPTT1AMUI
- OPTT1AMUI
- SES OPTT1AMUI
- TEC1A MUI Module
- TEC1A Multi-Unit Interface
- MUI module for units without modem or COMM options
- RPT1AMUI - related replacement/service reference
Technician Note
Before ordering, check the existing TEC1A option package. If the unit already has OPTT1AMODEM or OPTT1ACOMM, MUI functionality may already be included depending on the configuration.
Important Ordering Warnings
- One MUI is required for each TEC1A unit placed on the shared line.
- Do not confuse OPTT1AMUI with OPTT1AMODEM or OPTT1ACOMM, which include additional communication functions.
Before Ordering
- Confirm the unit is TEC1A, not TEC1, TEC2, or CAT.
- Confirm the system needs multiple units on one telephone line.
- Count how many TEC1A units will share the line.
- Check whether each unit already includes MUI through another option board.
- Verify installer access and low-voltage power is off before internal board service.
Professional Advisory
Internal telephone entry option boards should be installed by a qualified access-control technician. Power and telephone circuits should be handled safely, and unit programming should be checked after installation.
Product Questions & Answers
What does the OPTT1AMUI module do?
It adds Multi-Unit Interface line-sharing capability for compatible TEC1A units that will not use modem or COMM option boards.
How many MUI modules are required?
SES notes that one MUI is required for each unit placed on a single shared telephone line.
Is this a modem board?
No. It is the MUI module only. OPTT1AMODEM is the option that includes modem, MUI, and serial functions.
Does it work with CAT Series systems?
This part is for TEC1A applications, not CAT expansion systems.
Could my TEC1A already have MUI?
Yes. Some Deluxe, Premium, modem, or COMM configurations may include MUI, so the existing option package should be checked.
