The Westermo TR-36 is an advanced rack based industrial RS-422/485 telephone modem designed to satisfy industry’s demands for reliability and functionality, even in the most exposed and exacting tough environments with high levels of interference and large temperature swings.  It is approved and supported for use in the North American (UL and FCC), South American and European Union (CE) markets, as well as in the other regions of the world with a single unit.
  The TR-36 is particularly well suited for use with PLCs, water/wastewater control systems, outdoor signs and power generation and transmission equipment as well as other applications.  With tri-galvanic isolation, transient protection, LED diagnostic information, an extended temperature range, and wide power supply capabilities it simplifies industrial installations, increases their flexibility, and supports incredible customer service possibilities.
  A “fall-back” mode is supported when using the TR-36 with both dial-up and leased lines.  In the rare case that a leased line will fail, a dial-up telephone line connection is negotiated and data communications are automatically restored.  Then, periodically, the leased line is checked until that connection can be re-established.
  Additional features include password protection, dial-back security and caller ID answering to ensure that only authorized users can communicate with the modem and any connected equipment.