Peter Campbell

--Peter Campbell--
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--Peter Campbell--

Peter is the Marketing & Sales Co-Ordinator at i-A.C.Systems.


Peter Campbell
On 11/19/15, 7:45 AM

Unfortunately the PCO2 controller has been phased out by Carel a few years ago and is no longer available. The PCO2 has been entirely replaced by the PCO3 controllers which are PIN-to-PIN compatible hardware. This has the same sizes, same input/output configurations of the PCO2.

The main difference between these 2 platforms is the processing speed. The PCO3 is twice as fast and is more powerful!

You can replace the PCO2 with the corresponding PCO3 model, however, with regards to the software this may not be a straight forward "Copy-Paste" replacement procedure through a smart key because of the processing speed of the microprocessor.

There are a couple of ways to go about this software issue:

1) The first is: If you hold the software files from the manufacturer of the unit, then we could install in the controller an "emulation" bios that would fake the processing speed of the PCO3 to the one of a PCO2 controller. This patch would allow you to use a software compiled for PCO2 controllers into a PCO3 without problems... But remember, you need the Application (or software) files from the Manufacturer for this operation.

2) The second is: If the AC unit instead is using one of the Carel Standard software applications (the software code/part number would start with a code "FLSTDm" and would be typically found in the information masks of the software), it is quite likely that the software has been made compatible the the Carel Software Department also for PCO3. In this case the upgrade to the new controller is much easier, as you can replace the controller for the new one and use the same software but with of the latest version.

Please read below for more information about the compatibility of the two platforms:

Hardware differences:

From the hardware point of view, the differences between pCO2 and pCO3 are as follows:

- Elimination of the external fuse. The pCO3 uses an internal fuse with automatic reset.

- pCO3 has no dipswitches for setting the address of the board in the pLAN. The procedure is managed by software, in the same way as for the pCO1 and pCOXS.

- The optional boards for the serial BMS on the pCO2 are not compatible with the pCO3. In fact, the pCO3 uses the pCO1 optional boards for the serial BMS and Field-Bus.

- pCO3 has an additional terminal to supply the ratiometric pressure probes. If these are not used, simply do not connect the corresponding terminal.

- Analogue outputs 5 and 6 on the pCO3 Large have the same response speed as the first 4 analogue outputs. On the pCO2these two analogue outputs took around 15 seconds to go from 0 V to 10 V and vice-versa (see the paragraph Additional checks on the following page).

- pCO3 has a connector to supply the Aria terminal. 


Software differences and checks to be performed

pCO3 requires a new bios to manage all the new functions, such as the NAND Flash, Built-In terminal, ratiometric probes etc. Compatibility has been maintained for the functions developed in the past.

In addition, the use of a double quartz on pCO3 guarantees almost double the communication speed over the pLAN networks with pCO3 and pGD2-3 terminals only, as well as compatibility with the other boards in the pCO family (pCO2, pCO1, pCOXS) in the case of mixed pLAN networks.

From the EasyTools software point of view, on the other hand, a number of checks are required in those applications where the same software works on different platforms. The various cases are shown below.

EasyTools software for pCO2 with pGD* terminal

In this case there is compatibility as regards the EasyTools software. In addition, all the functions developed previously to manage the external pGD* terminal (bitmaps, different fonts etc.), are also compatible with the new Built-In terminal.

EasyTools software for pCO2 with pCOT / pCO-i terminal

In this case too there is compatibility as regards the EasyTools software.

EasyTools software to manage applications on different hardware (pCO2, pCO1, pCOXS) In this case, to enable the various functions of the EasyTools application, very often a check is performed on the type of hardware that the software is used on. If these checks are featured in the EasyTools application, then the software needs to be changed so as to enable the functions used on the pCO2 on the pCO3 too.

Additional checks

On the pCO2 analogue outputs 5 and 6 took around 15 seconds to go from 0 V to 10 V and vice-versa. On the pCO3, on the other hand, these analogue outputs have the same response speed as the first 4 analogue outputs. If this characteristic was exploited on the pCO2 to manage special devices, then the EasyTools software needs to be changed to use analogue outputs 5 and 6 in the same way as on the pCO2.

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Asked: 11/19/15, 7:44 AM
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Last updated: 8/7/17, 6:59 PM