The pCO² occupies the top-level position in Carel's 16 bit OEM programmable controller series. It has been designed to satisfy a wide range of applications in the air-conditioning and refrigeration fields. pCO² controllers are available in three different sizes, according to the I/O and power requirements: pCO² Small, pCO² Medium, pCO² Large. The pCO² is powerful and flexible, excelling at controlling large-size roof top units, precision air conditioners for telecom and data centers, modular chillers, desiccant dehumidifiers, air handling units, energy recovery and make up air units, compressor racks and many other applications in the HVAC and refrigeration markets.

Thanks to EasyTools, the graphical application program development package for all Carel OEM programmable controllers, software portability is a snap. Application programs designed for other Carel programmable controllers are easily implemented to newer hardware platforms, preserving any investments made on prior controllers.

The pCO² features mechanical relays and solid state relay outputs (SSR, see I/O specifications here) and comes with a built-in user-interface, avoiding the expense of a remote terminal. It accepts a variety of sensors in the market such as Carel's NTC temperature sensors, 0-1Vdc, 0-20mA, 4-20mA, 0-5Vdc ratiometric transducers, and dry contacts.

Several user interfaces including display and keypad are also available in conjunction with the built-in LCD display: graphic backlit LCD display, alphanumeric LCD display, backlit alphanumeric LCD display, and LED display are all provided in wall-mount or panel-mount plastic enclosures.

The graphic display models are capable of showing symbols and trends in graph form for easier data-comprehension. Icon-based languages, such as Chinese, Japanese, Cyrillic, or Arabic are all supported. Any of these terminals can be brand-labeled  with the OEM's name, colors and logo.

pCO² series boards are supplied in plastic enclosures that guarantee the high mechanical protection of the board and reduce the risk of electrostatic discharge due to incorrect handling; quick DIN rail mounting means faster assembly and wiring. Expansion I/O boards are also available.

Thanks to a variety of plug-in serial cards and external gateways, pCO² can share data with any popular Building Management System (BMS) in the market. BacNet^TM, Lonworks^®, Modbus^®, SNMP, JCI's N2 Open^®, and Trend/Novar protocols are all compatible. The pCO² can also be connected to a modem for remote communication to a supervisor, or to send SMS messages to GSM cellular phones. Data communication to Intranet//Internet networks is also available by using a gateway(WEBG0000B0) that converts Carel protocol to 10Mb/s TCP/IP Ethernet^TM protocols (FTP, HTTP, SNMP).

In addition to the serial port mentioned above, the pCO² features a pLAN (pCO Local Area Network) port for intra-controller communication. This enables up to 32 controllers to share data together, or it can be used to expand available I/O. More importantly, the pLAN port makes achieving an intelligent distributed architecture possible: including master/slave relationships, redundancy, modular controls, and lead-lag operation can all be implemented. 

The pCO²'s high memory capacity (up to 6MB of FLASH RAM) stores the application and parameters permanently, preventing data loss in the event of power failure and without requiring a battery backup! Troubleshooting is made easy by logging alarms and other events, such as temperatures, status of controlled devices, and date/time into the expansion memory. ("Black Box" mode). The recorded data can also easily be transferred to a PC  (locally or via modem) and opened using Excel for analysis. Can this be true? Come see for yourself!