System Enhancement Module (SEM) with CDMA Cellular Communicator

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(based upon one review)

The System Enhancement Module or SEM marks the first product to integrate Honeywell alarm communications with the pla...

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The System Enhancement Module or SEM marks the first product to integrate Honeywell alarm communications with the platform. The SEM is essentially a glorified 3G CDMA cellular communicator that uses the robust Verizon cellular network to transmit signals from a traditional Honeywell/ADEMCO VISTA low P-series alarm system. This compatibility includes the VISTA-10P, 15P, 20P, 21iP and their First Alert equivalents. The VISTA-20P is one of the most common alarm panels in the United States. There are limitations. The panel must have a manufactured date of 2005 or later. This is printed on the PROM chip located on the board.

Traditionally, Honeywell kept all alarm communication in house with their daughter company, AlarmNet. Although AlarmNet offers similar services to in the form of the Total Connect 2.0 app, offers a wide range of integrations stretching from Nest thermostats to voice activation via Alexa and apple home kit devices.

The SEM wires into ECP keypad bus to the ground and data connections. Generally ECP devices draw power from the VISTA panel's 12VDC output. However the SEM draws from the panel's backup battery. There is a red wire that comes with the device. Inside the cable there is a fuse designed to protect the SEM and alarm panel from any shorts. After you install the SEM, there are some simple changes required before registering with an dealer.

The SEM uses keypad address 23 by default so you will want this address to be open and set to partition 1. If it is in use you can change the keypad address by following the steps in the installation manual. Since allows you to manage user codes from the web login and app, you will need to delete all your user codes from the panel. You can add them back at the keypad locally or through the app after it has been setup.

Brand: ADC-SEM100-CDMA Compatible Products

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Outdated SEM Device
Submitted on 07/15/2020 Alarm Grid

The ADC-SEM100-CDMA is a discontinued Cellular Communicator for Honeywell VISTA Security Systems. This device is one of many System Enhancement Modules (SEMs), which are used to connect various security system with and provide them with remote Z-Wave control. Having an SEM device for a Honeywell VISTA System is somewhat unique, as it will allow you to use the system with as its interactive monitoring and automation platform. Normally, a Honeywell VISTA System would use Total Connect 2.0 for this purpose. But if you prefer to use with your Honeywell VISTA, then an SEM is for you. But we do not recommend the ADC-SEM100-CDMA for this purpose. This is because it communicates across the Verizon CDMA Network, which is being shut down in the coming years. Instead, we recommend using an LTE module instead. Coupled with the fact that the communicator is discontinued, we only give it a 3 Star rating.

There are some aspects we liked about the ADC-SEM100-CDMA. For one, it allowed for connectivity with This is a great interactive platform for controlling your system remotely. You can access the service from virtually anywhere to arm and disarm your system, check system status, control Z-Wave devices, and more. And since the ADC-SEM100-CDMA has a built-in Z-Wave controller, you will be able to build an automation network around the system. Just be aware that all Z-Wave devices will need to be controlled remotely through Since this is a cellular communicator, it provides reliable cellular service when active.

But the downsides regarding the ADC-SEM100-CDMA should not be ignored. For one, it is discontinued, and it can no longer be purchased new. You shouldn't purchase a used model either, as the ADC-SEM100-CDMA can no longer be activated for monitoring service. This is because the Verizon CDMA Cellular Network is being shut down soon, and no longer allows new CDMA activations. If you have an existing ADC-SEM100-CDMA, then it will continue to work until Verizon shuts down their CDMA network. But once the network is shut down, then the communicator will no longer work at all. Therefore, you should upgrade to an LTE communicator as soon as possible. A good SEM device for a VISTA that uses LTE connectivity is the ADC-SEM210-VT-VZ. With these downsides in mind, we give the ADC-SEM100-CDMA a 3 Star rating.

Good:, Built-In Z-Wave, Reliable Cellular Communication

Bad: Discontinued, Can No Longer Be Activated, Will Stop Working Once Network Shut Down

Bottom Line: 3 Stars

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