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UPLC-ll Universal Power Line Carrier


The Most Economical Medium for Protective Relay Communications!

As with our previous UPLC power-line carrier design, UPLC-II requires no hardware modifications for most required configurations. UPLC-II is frequency programmable across the entire power-line carrier spectrum (30 to 500 kHz) without changing any hardware components. UPLC-II can be software configured either as an ON/OFF or frequency-shift keyed (FSK) power-line carrier unit without changing any hardware components. This flexibility makes each UPLC-II universally suited for any directional comparison blocking, permissive, phase comparison or transfer trip protective relay application.

UPLC-II is fully programmable using a simple-to-use web browser interface, which offers many benefits for the user. First, a web browser is often installed on a personal computer at the same time as the operating system. This removes the need to have administrative rights to install proprietary interface software. Secondly, since the web browser is used for other applications, the user is familiar with browser functionality. Lastly, the web browser screens are dynamically updated to reflect status of the unit.

Since UPLC-II is fully programmable, the settings can be uploaded via any of the communication ports. Setting files are in the Extensible Markup Language (XML) format, which can be easily modified if desired. With the XML format, the unit will be compatible with future intelligent electronic devices (IEDs). Settings may also be applied from the factory defaults which are stored in the unit. The user has choices for the most commonly used types of protection systems.

In the ON/OFF (AM) mode, there is Directional Comparison Blocking or Phase Comparison Blocking for line relaying. In the FSK mode, there is Directional Comparison Unblocking (DCU)/Permissive Overreaching Transfer Trip (POTT) for line relaying. Direct Transfer Trip is also offered for equipment protection in the FSK mode. A combination of DTT and DCU/POTT is available with the 3 frequency setting in the FSK mode. Additionally there is 4-Frequency FSK mode that allows two inputs to key independently or simultaneously to produce received outputs for a command A trip, a command B trip or a command A & B trip.
Self-calibration provides for ease of installation and maintenance. AMETEK was the first to introduce a self-calibrating receiver. Now the UPLC-II incorporates this plus a self-calibrating transmitter. No longer are instruments needed to calibrate an individual transmitter/receiver. Accurate measurements for the transmitter output and the received signal level are displayed on the front of the UPLC-II and on the web page.

Transmit reflected power measurement is included on the UPLC-II. While this cannot take the place of a reflected power meter when tuning the high voltage equipment, it can provide an SOE and alarm output to track decreases in the tuning efficiency of the line and give an early warning to equipment problems as well as identifying which end of the line has an issue. Reflected power readings are available on the front of the unit, through the TEST button or on the home web page of the UPLC-II.


  • NEW TX Reflected Power Meter with frequency selectivity– Continuous Monitor that is unaffected by other Transmitters at different frequencies
  • NEW Fast Ethernet front port interface (only with Ethernet option)
  • NEW Significantly Improved Protective Relaying Security and Dependability
  • NEW IT Management User Interface via Ethernet
  • Programmable for either FSK or ON-OFF Applications
  • Fully Frequency Programmable from 30 to 535 kHz in 0.01 kHz Increments
  • Bandwidths and Frequency Shifts Selectable
  • FSK Units Settable for 2,3, or 4-Frequency Applications
  • All Software Configurable Items are set via Standard Web Browser
  • Integrated HMI with Front Keypad and 4x20 Character Plasma Display
  • Unit can be programmed to match any narrowband PLC at remote end, excluding voice or checkback functions.
  • Fully Compatible with TC-10B Checkback and TCF-10B Trip Test and UPLC testing capabilities.
  • Built-in meters continuously display Transmit & Receive Levels
  • Automatic Receiver Sensitivity Settings
  • Sequence of Events, Time-Tagged with 1-ms Accuracy for most Events
  • IRIG-B Input (Both Modulated and TTL)
  • 48/60 Vdc or 110/250 Vdc Powered
  • Inputs: 5 Keying Programmable Inputs (Current Limited, High Threshold, & Optically Isolated)
  • Outputs: 7 Programmable Solid State, 3 Programmable Contacts
  • Standard 19 Inch Chassis Mounting, 3 Rack Units

Meets or Exceeds All Applicable IEC and ANSI Standards

*Firmware Download Note: UPLC-II Release Package 4.06 is the latest firmware for units that shipped before May 2019 with Transceiver Board hardware rev. 13 or lower. UPLC-II's that shipped approximately May 1, 2019 or later with Transceiver Board hardware rev. 16 or higher all originally shipped with and use firmware version 5.02 only. 

Internal PPC Firmware - 4.06
(SHA-256 Hash Code = c510802e36bd496d70a833b6d42a3b114a476598f566ced911456a008de39f8e)

Internal PPC Firmware - 5.02
(SHA-256 Hash Code = f648d17c2defa320c3bcdb4ba45c182bf2077009215ea6132c3fe2687a0c810c)