The LSM-81 is a compact alarm module for public GSM and LTE networks and the successor to our GSM-2110/4110 series. It can also function as an LTE-RTU (remote station) in conjunction with the MDP-810 central station, including in mixed operation with time-slot radio devices.
The base unit features 8 digital inputs, 8 digital outputs, and 2 analog inputs (0/4–20 mA, optionally 0–10 V). All inputs and outputs are galvanically isolated.

Using PEM-series expansion modules, the inputs and outputs can be expanded to up to 24 digital inputs/outputs and 10 analog inputs.

LSM-81 as an Alarm Module:

For alarm notifications, 24 binary and 8 analog alarm blocks are available. For each binary alarm block, various conditions of the digital inputs (AND, OR, INVERSE, XOR) can be configured to trigger an alarm. For analog alarm blocks, alarms can be triggered by exceeding or falling below analog values.
Each alarm block includes additional features such as adjustable acknowledgment wait time, activation delay, re-alarming time, the inclusion of the alarm trigger timestamp, the device name, or a configurable output action.

LSM-81 as an LTE-RTU:

When used with the MDP-810 radio controller, which must be accessible via an IP address, the LSM-81 can also function as an RTU remote station or mini-PLC, particularly in applications such as water and wastewater management, energy supply, and photovoltaics. It can be integrated into existing time-slot radio networks while retaining its alarm module functionality, allowing alarms to be sent directly to smartphones.