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For Far Off Places

Technical Specifications

  • Type:

    RS-485/MODBUS Interface

  • Quantity:


  • Protocol:


  • Connector:

    1 set of 4-position screw terminals (3.5 mm)

  • Power:

    24 Vdc

Technical Specifications
Making The Connection

Hooking Up The Modem

Sending status notifications and alarms via satellite can be accomplished by hooking up the satellite modem to the MODBUS/RS-485 port of the RIO xR3.

Optima recommends installing a zener barrier or surge protector wherever the wiring leaves the shelter for added safety.

The examples below depict how to power the satellite modem from the built-in power supply, or an external source.

Using the built-in source has the added advantage that the power output is backed up by the built-in standby battery.

This allows sending a ‘last gasp’ message before everything shuts down in case of prolonged power outages.

Satellite modem and MODBUS devices can be mixed and matched on the same bus.

Clear View Of The Sky

Mounting The Modem

Follow these simple recommendations when mounting the modem:

  • Affix the satellite modem to the mounting bracket, using the supplied hardware.
  • Mount the bracket to a pole or cell tower.
  • The modem requires an unobstructed view of the sky.
  • Do not mount indoors.
  • Do not install close to tall buildings, solid structures or trees.
  • Use supplied bracket for easier installation.
  • Ensure to mount the modem on a level plane.
  • Do not affix to walls or under roof overhangs.
  • Fill connector with gel to create a water tight seal.
  • Securely attach the outdoor cable to the satellite modem.
Sending Alarms Via Satellite


Satellite companies tend to count every bit of data exchanged over one of their long range links.

As bandwidth budgets are counted in bytes (not Megabytes or Gigabytes as in other industries), it pays to be very efficient when doing remote monitoring.

Optima developed ALARMS UPLINK, a compression technology that manages a 40:1 reduction in size. This makes sending alarm notifications via satellite viable and affordable.

The RIO xR3 runs a scheduler to make sure all relevant messages get queued up — and sent to the LEO (Low Earth Orbit) satellite as soon as they are ready for transport.

This guarantees that there are no duplicated or missed alarms.

Keep in mind that these inherent limitations render the satellite link unsuitable to remotely manage the RIO xR3. This is due to the extremely limited bandwidth and data budget allowance per month.

Consult our ALARMS UPLINK page for more details on the exact produres involved in delivering alarms via satellite.

Satellite Modem Connection

MODBUS Devices + Satellite Modem
  • I/Os

    1 MODBUS (A/+, B/-)

    1 DC Power (PWR, RTN)

  • Connectors

    1 x 4 position

  • Pluggable
  • Type
    Screw Terminal
  • Pitch