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Sentinel SMS  is a professional system of remote monitoring for security and automation of remote environment. This two-way Remote Control System allows, using a normal phone to make reading of analogical sensors and transducers ( e.g. temperature, humidity, pressure, level, etc..) installed in the remote station,  and to receive alert  by overcome  of minimum and /or maximum threshold and alarms from ON-OFF sensors contact ( burglar, fire, flooding, etc..) connected to the digital lines of SENTINEL.

It is possible also to control 8 relays in bi-stable mode simply sending SMS or in mono-stable mode at zero cost with a call ring to activate, for example, a motorized gate opener or other load requiring short pulse activation. SENTINEL SMS automatically sends a call or, alternatively a confirmation SMS to the caller, if is received a valid command by a registered caller, while SMS transmitted by  unregistered  callers are  ignored  and deleted  without  execution. SMS containing a valid command is executed and then automatically deleted from the SIM. SENTINEL SMS can also implement a local embedded ON-OFF automatic control, enabling the appropriate user parameters and setting the minimum and maximum threshold levels, the related relays are controlled and activated as function of temperature and voltage level.

You can preset up to 8 alarms for minimum and maximum set-point, both voltage and temperatures. There are also 8 digital input lines TTL level,  whose change of state (one or more inputs) let send an alert SMS reading the state of all inputs. The analogical and digital alarm management is very complete, allowing a precise analysis of environmental conditions remotely controlled. The system generates an  alarm cycle when the threshold is over, i.e. temperature and/or voltage and the current alarm status is stored on the EEPROM; when the sensor reading falls to normal level, which is below the threshold, there is a second cycle alerts (SMS or call) to indicate that signals (analogical and/or digital) are returned to normal level. The digital alarms are trigged by opening one or more input lines that are normally closed to ground; It is available a pre-alarm delay,  (0 to 255 s)  within which there is no alarm generation, but it is only displayed  the warning for  opened line and  elapsed time. The typical fields of application of SENTINEL are: remote activation of heating systems and boilers, air conditioning systems, lighting, irrigation, burglar alarms, etc.. and remote opening of doors and gates, as well as control of remote environments, with the possibility of receiving alarms generated by environmental remote sensors and reading sensors and transducers.

THE SENTINEL SMS is equipped with a 2×20 backlighted LCD useful for the detailed view of all phases of the operations and the messages received by the modem, the readout of the 8 analogical input voltage (0-3 V) with a resolution of 10 bits (remote sensors and transducers, for liquid level, pressure, etc.) and for displaying the state of the digital input lines and relays. The SENTINEL SMS also has an independent functions of ON-OFF automatic control: enabling the appropriate parameters, you can implement a controller that controls up to 8 relays, as a function of temperature or voltage input, prefixing the minimum and maximum set-point. To make a better control function and avoid oscillations around the threshold value (set point), there are two correction factors hysteresis, low and high, settable by the user, the default factory setting is set at 1% (IST-low = 0.99, IST-high = 1.01). It ‘also possible, by setting the appropriate parameters, enable the activation of the relay according to the state of digital lines, and then repeat the alarm on a line corresponding relay (eg open line 1 -> 1 relay activated). All phases of entry and exit from the analogical and digital alarms are indicated on the LCD. The enabling of the various alarms are made by writing the appropriate parameters in the relative locations of EEPROM.

Technical Data

  • GSM  Dual Band MODEM 900-1800 MHz with Aerial SMA connector

  • Bi-directional Control System receiving and sending SMS

  • 29.412 MHz clocked – 64 kB Flash, 2,4 kB RAM, 2 kB EEPROM

  • SIM Card standard reader built into GSM MODEM board

  • 8 Relays Outputs with SPDT 10 A 250 V contacts and optical-couplers

  • 8 Analogical Inputs with 10 bit resolution in the 0-3 V range

  • 8 Digital TTL level Inputs with reading of state an alarm trigger

  • 8 Status LED for relays control

  • Bi-stable command via SMS to control each of 8 relays

  • Mono-stable command no cost ( automatic rejection)

  • Up to 250 registered users, 9 of which for receive alarms

  • Automatic Answer by ring or sending SMS to registered caller

  • Compiled Firmware Flash resident upgradable by PC via RS232C

  • Supervision by analogical thresholds min, max and ON-OFF control

  • LCD Module 2 lines x 20 characters with LED backlight

  • RS-232C Serial Interface for parameters setup and upgrade download

  • Standard IDC 2,54 mm connectors for  flat cable and screw terminals

  • Power 250 Vac or 12VDC with automatic relays switch anti blackout

  • Dimensions: Standard Rack 2U x 280 mm

  • Screw DIN Terminals Rear positioned 44 poles

  • User Manual and software utilities for download on CDROM

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