CAREL PGD Handheld Operator Configuration Replacement

CAREL PGD Graphic Handheld Installation, Configuration, and Old System Replacement Complete Guide

In the fields of HVAC, refrigeration, and building automation, CAREL's PCO series programmable controllers are widely used in chillers, heat pumps, air conditioning terminals, and refrigeration equipment. The PCO/PCOT series text controller, which is matched with it, serves as a human-computer interaction interface and has long been responsible for functions such as parameter viewing, setting value modification, and alarm display. However, with the gradual discontinuation of PCO/PCOT series products and the increasing demand for graphical interfaces and multilingual support from users, alternative solutions have become an urgent need.

The PGD graphic handheld devices (PGD0000N00, PGD1000N00, PGD1000NW0, etc.) launched by CAREL are designed to solve this problem. It is fully compatible with older PCO/PCOT terminals, supporting graphical icon display, international fonts, and a wider operating temperature range (-20~60 ℃), while retaining the original communication protocol and wiring methods. Starting from the perspective of on-site replacement and debugging by engineers, this article systematically outlines the installation steps, address configuration, PLAN network communication settings, and common troubleshooting methods for PGD handheld devices, helping users quickly and safely upgrade and replace old terminals.

Overview and Selection Comparison of PGD Handheld Devices

1.1 Product positioning and compatibility

The PGD series graphical controller is a remote human-machine interface designed specifically for CAREL PCO controllers. Its biggest feature is full backward compatibility with old PCO/PCOT text terminals, which means:

No need to modify the application software on the PCO motherboard.

The communication protocol (such as PLAN, point-to-point) and physical interface (RJ12 telephone line) remain unchanged.

The original wiring and installation hole sizes are basically compatible, only minor adjustments are needed.

Therefore, when the old terminal on site experiences screen aging, button failure, or needs to be upgraded to a graphical interface, PGD is an ideal direct replacement product.

1.2 Model Code and Selection

According to display size and backlight color, the PGD series is divided into the following main models:

Model Code Display Pixel Backlight Color Applicable Scenarios

PGD0000N00 120 × 32 green simple text and basic icon, replacing PCO/PCOT

PGD1000N00 132 × 64 green larger display area, supporting richer icons

PGD1000NW0 132 × 64 white is the same as 1000N00, with a softer white backlight

In addition, there is a PGDN version without buttons and LEDs, which requires an external membrane keyboard (up to 8 keys+3 LEDs). In conventional replacements, integrated models with buttons are more commonly used.

1.3 Key Characteristics

Graphic management: It can display pre-defined icons in application software and support international fonts (5 × 7 or 11 × 15 pixels).

Wide temperature range: -20 ℃~60 ℃, suitable for harsh environments such as refrigerated warehouses and outdoor cabinets.

No local program: The handheld device itself does not require downloading programs, and all screen logic is defined by the PCO motherboard and automatically adapts after replacement.

Communication interface: RJ12 (6P6C) telephone line interface, the maximum communication distance depends on the PLAN network capability of PCO (usually up to several hundred meters).

Mechanical installation and electrical wiring

2.1 Requirements for panel openings

The PGD handheld device is designed for embedded panel installation and fixed with welded column head bolts. The installation panel thickness should be at least 2mm to ensure that the display area is not obstructed by panel deformation.

Hole size (refer to catalog Fig.8, Fig.9):

PGD0 series (120 × 32): Panel opening 78 × 30mm.

PGD1 series (132 × 64): Panel opening 74 × 39mm.

In addition, a small hole (at least 40 × 10mm) needs to be opened on the installation panel for flat cables to pass through. This flat cable is used to connect the internal button circuit of PGD (only when using models with buttons). When wiring, pay attention to protecting the cable to avoid being cut by metal edges.

2.2 Electrical connection steps

Power off operation: Before making any wiring, ensure that both the handheld device and the PCO motherboard are powered off.

Connect the flat cable: Insert the flat cable at the back of the handheld device into the PGD dedicated interface, paying attention to polarity. Pin 1 is marked with a "D" symbol in the interface.

Connect RJ12 communication cable: Use a standard telephone type cable (CAREL S90CONN00 * series or self-made cable), with one end inserted into the RJ12 interface behind the PGD and the other end inserted into the corresponding terminal interface of the PCO motherboard (usually labeled as "TERM" or "PGD").

Power on inspection: Connect the PCO motherboard power supply, and the PGD should automatically start and display the default interface or "NO LINK" to establish communication.

Attention: It is recommended to use shielded twisted pair cables for RJ12 cables, with a length not exceeding 100 meters (depending on the PLAN network load). In strong electromagnetic interference environments, cables with metal shielding layers should be used and grounded at one end.

Address setting and communication configuration

The communication between PGD controller and PCO motherboard is based on CAREL's PLAN network or point-to-point protocol. Each PGD controller must have a unique address (1-31, or 0 for point-to-point) and match the 'Associated Controller List' in the PCO motherboard.

3.1 Enter configuration mode

When the handheld device is powered on, press and hold the "1" and "-" keys (i.e. the numeric 1 key and the minus key) on the keyboard for at least 5 seconds, and the display screen will enter the configuration interface (as shown in Fig.3). The cursor will flash in the upper left corner.

Note: Even if the handheld device currently displays "NO LINK" or "1/0 Board xx fault", this operation is still valid.

3.2 Modify the address of the handheld device itself

In the configuration interface:

Press the "1" key once, and the cursor moves to the "Address Value Area" (displayed as nn, default 32).

Select the desired address (1-31, or 0) using the "1" key (the original text may be up and down keys or plus and minus keys, but the document describes using the 1 key loop).

Press the "1" key again to confirm. If the new value is different from the previously saved one, a confirmation interface (Fig.4) will pop up. Press the "1" key to save it to non-volatile memory.

The special meaning of address 0: When the address is set to 0, a point-to-point communication protocol is used between the controller and PCO, rather than a PLAN network. At this point, the "0/board address" area is no longer displayed (as there is no need to select the motherboard). This mode is suitable for one-to-one connections and does not allow multiple handheld devices to share the same PCO.

3.3 Configure dedicated/shared controller (associated with PCO motherboard)

If it is necessary to modify the PCO motherboard controlled by PGD (for example, if there are multiple PCOs in a PLAN network and the controller needs to switch to controlling another one), follow the steps below:

In configuration mode, press the "1" key until the cursor moves to the "x0" area (formerly known as the "0/address" area, as shown in Fig.3 with values such as "0/12").

Press the "1" key to cycle through the PCO motherboard addresses that are currently online on the network. If the network is not working properly or an address does not exist, the area will display a "-" and cannot be modified.

After selecting the PCO address, press the "1" key again, and the screen will switch to the associated settings interface shown in Fig.5.

Use the "1" key to move the cursor between regions, and use the "1" key to change the value of the current region:

Px "area: displays the address of the selected PCO motherboard (e.g." P12 ").

Pin/Shared "area: indicates the type of handheld device. PGD cannot be set as "Sp" (shared printer) and can only be used as a dedicated or shared handheld device (depending on the PCO configuration). Usually, the dedicated mode is chosen.

Move to the "OK?" area, select "YES", and then press the "1" key to confirm. The new configuration will be saved to permanent storage.

Note: If there is no button operation within 30 seconds, the configuration program will automatically exit without saving any changes. This is to prevent accidental modifications.

3.4 PCO Side Association List Settings

In the configuration parameters of the PCO motherboard, there is a "list of dedicated and shared controllers". This list defines which operator addresses can access this PCO. If the PGD controller address is not in the list, communication cannot be established. Therefore, when replacing the old handheld device, it is necessary to ensure that the address of the new PGD is the same as the original handheld device, or modify the list through PCO configuration software (such as CAREL c.design).

Common fault signals and troubleshooting

4.1 “1/0 Board xx fault”

Phenomenon: The display screen shows "1/0 Board xx fault", where xx is the PCO motherboard address.

Reason: The handheld device detected that the associated PCO motherboard (address xx) is offline (such as power failure, communication line disconnection, or motherboard malfunction).

Solution:

Check if the power supply of the corresponding PCO motherboard is normal.

Check if the RJ12 communication cable is securely connected and if the core is broken.

Check the terminal resistance setting of the PCO motherboard (a 120 Ω resistor should be added to both ends of the PLAN network).

If the PCO motherboard has been replaced, the controller address and associated list need to be reconfigured.

4.2 “NO LINK”

Phenomenon: The display screen continues to show "NO LINK" without any other information.

Reason: The handheld device did not receive any signal from the PLAN network. Possible reasons include:

RJ12 cable disconnected or short circuited.

The address setting of the handheld device is incorrect (for example, set to 0 but there are multiple nodes in the network).

The entire PLAN network has no main station or all PCOs are not powered on.

Solution:

Check if the communication cables are intact, and use a multimeter to measure the continuity of each core (RJ12 pin definition: usually corresponding to 1-6, please refer to the PCO manual for details).

Confirm that at least one PCO motherboard has been powered on and is in operation.

Enter the configuration mode of the handheld device and check if the address conflicts with other devices in the network (the address must be unique).

If there is only one PCO in the network, setting the controller address to 0 (point-to-point mode) can simplify communication.

4.3 The screen backlight does not light up but the display is normal

Reason: The backlight LED is aging or the backlight setting is turned off.

Solution:

For white backlight models, the backlight is usually on by default. The backlight switch can be adjusted by long pressing a combination key (as defined in the application software).

If the backlight still does not light up, it may be due to damage to the internal LED and the handheld device needs to be replaced.

4.4 Button unresponsive or slow response

Reason: After long-term use, the conductive rubber may age, become waterlogged, or accumulate dust.

Solution:

After power off, remove the front panel of the manipulator and clean the conductive rubber and PCB contacts with anhydrous alcohol.

If the conductive rubber has hardened, you can try using a 2B pencil to temporarily improve the contact points, but it is recommended to replace the handheld device.

The complete process of replacing old PCO/PCOT terminals with PGD

Many devices on site are still using early PCO/PCOT text controllers (such as PCOT00, PCOO series). When these terminals malfunction or need to be upgraded, replace them with PGD according to the following steps:

5.1 Preparation work

Record the original controller address: View its PLAN address in the original controller configuration menu (usually displayed on the boot screen or parameter list). If unable to view, you can temporarily use PGD to scan the network.

Confirm PCO model and firmware: PGD is compatible with mainstream models such as PCO *, PCOe, PCO3, etc., but it is recommended to confirm that the firmware version of PCO supports graphic display (generally supported by firmware after 2005).

Purchase matching PGD models: If the original handheld device displays single line text and only basic parameters need to be viewed, PGD0000N00 is sufficient; If you need to display a trend chart or more information, select PGD1000N00/W0.

5.2 Physical replacement steps

Power off: Disconnect the power supply of the PCO motherboard to avoid damaging the interface during live plugging and unplugging.

Dismantle the old handheld device: Remove the old terminal panel, unplug the RJ12 plug and flat cable (if any).

Installation of PGD: Adjust the installation holes according to the opening requirements in Part 2 (note that PGD0 and PGD1 have different sizes), and use adapter plates if necessary. Embed and secure the PGD panel.

Connecting cable: Insert the RJ12 cable into the interface behind the PGD (with no polarity direction, but it needs to be fully inserted). If the old system has a flat cable, insert it into the D interface of PGD (note pin1 alignment).

Set Address: After powering on, enter configuration mode and set the PGD address to the same value as the original controller. If the original address is unknown, it can be temporarily set to 1 and then queried on the PCO end.

Test communication: Observe whether PGD displays PCO menus and variables normally. If 'NO LINK' is displayed, check the address and cable.

5.3 Adjust the PCO side association list (if necessary)

If PGD has set the correct address but still cannot communicate, it may be due to PCO's "controller list" restricting access. At this point, it is necessary to connect to PCO programming tools (such as c.design or pCOSoft), find the "Terminal list" parameter, and add the address of PGD to the shared or dedicated list. Alternatively, set the list to "Allow All" (value 0).

5.4 Functional Verification

Test each button one by one to confirm that the functions of page up and down, numerical modification, confirmation, and exit are normal.

Check if the graphical interface is displaying as expected (PCO application software may need to support graphics, otherwise it will still be displayed as text).

Simulate alarms (such as disconnecting sensors) and verify whether the alarm information can be displayed correctly.

Summary of Application Scenarios and Advantages

6.1 Typical Application Scenarios

Refrigeration unit: Replace aging PCO terminals, display evaporator temperature, condensing pressure, compressor status, etc. graphically.

Air conditioning terminal: used for fan coil unit controller to achieve indoor temperature setting, wind speed adjustment, and fault code display.

Heat pump system: Display advanced information such as defrosting cycle, auxiliary heating, energy efficiency ratio, etc.

Remote monitoring: In conjunction with the PLAN network, one PGD can rotate and monitor multiple PCO devices.

6.2 Advantages compared to old terminals

Features: Old PCO/PCOT PGD graphic manipulator

Display method: Character LCD, fixed field dot matrix graphics, programmable icons

Language support is usually limited to English or a few fixed languages, with international fonts that can be customized for multiple languages

5-8 buttons, fixed 5 functions (for menu navigation), flexible definition

Working temperature range from 0~50 ℃ to 20~60 ℃, more suitable for cold chain environment

The replacement cost has been discontinued, and the spare parts are expensive and directly compatible, without the need to modify the program