When deploying industrial control computers in industrial control cabinets, the reliability of power connections, the standardization of switch logic, and the effectiveness of heat dissipation design are directly related to the long-term stable operation of the system in harsh environments. The Beckhoff C63xx-0020 series control cabinet industrial PC is designed specifically for use with DVI/USB control panels (CP68xx/CP78xx), offering six different model choices from compact C6320 to high-performance C6350, covering diverse configuration requirements such as optical drive, fan, and expansion slot. This article will be based on the technical manual of the C63xx-0020 series, and provide an in-depth analysis of the PC-ON and Power Status collaborative shutdown logic, assembly process of 5-pin power connectors, differences in heat dissipation design among different models, UPS battery pack configuration specifications, and mechanical installation size selection of this series of industrial computers. It will provide a full process technical reference for system integrators and on-site engineers from cabinet installation to power wiring.
Chapter 1: Overview of Product Series and Model Differences
1.1 Hardware configuration differences of six models
The C63xx-0020 series includes six models, and their core differences are reflected in the heat dissipation method (with/without fans), storage medium (hard disk/flash drive), and optical drive configuration:
Model, heat dissipation method, storage medium, optical drive size (width x height x depth), weight
C6320-0020 fanless (heat dissipation fins) 2.5-inch hard drive without 93 × 196 × 226 mm 4.0 kg
C6325-0020 Fanless (with heat dissipation fins) Flash Drive (without mechanical components) No 133 × 196 × 226 mm 6.0 kg
C6330-0020 fan cooling 2.5-inch hard drive with (Slim Line CD-ROM) 107 × 196 × 226 mm 4.6 kg
C6335-0020 fanless 2.5-inch hard drive with (Slim Line CD-ROM) 147 × 196 × 226 mm 6.6 kg
C6340-0020 fan cooling 2.5-inch hard drive without 134 × 196 × 226 mm 4.5 kg
C6350-0020 fan cooling 2.5-inch hard drive with (Slim Line CD-ROM) 148 × 196 × 226 mm 5.1 kg
Key selection tips:
Fanless model (C6320/C6325/C6335): Passive heat dissipation is achieved through the heat dissipation fins on the right panel, supporting up to 55 ° C ambient temperature operation, suitable for situations with high dust or inconvenient maintenance. The C6325 uses a flash drive instead of a mechanical hard drive, with no mechanical moving parts and the best shock resistance.
Fan cooling model (C6330/C6340/C6350): Equipped with an internal cooling fan, it has higher cooling efficiency, but there is a risk of mechanical wear and dust inhalation, and the fan operation status needs to be checked regularly.
1.2 Chassis Structure and Opening Process
The C63xx series chassis adopts a sliding top cover opening design, which is extremely easy to operate:
Use a screwdriver to loosen the fixing screw (1) at the front of the top cover by one turn (without completely unscrewing it).
Pull the plastic cover plate (2) forward to release the top cover latch.
Slide back and lift the aluminum top cover (3) to fully open the chassis.
Important note: For models with fans (such as C6350), be careful not to damage the power cord (1) of the fan when lifting the top cover.
Chapter 2: Power Connection and Intelligent Switching Logic
2.1 Definition of pins for dual 5-pin connectors
The C63xx-0020 is equipped with a 10 pin dual row plug (actually divided into upper and lower 5-pin connectors), which serves three main functions: power input, power on/off control, and UPS battery connection. This design physically separates the main power circuit from the control signal circuit, improving the safety and clarity of wiring.
Function Description of Connector Pin Signal
Upper row (control signal) 1 PC-ON shutdown trigger input (24V valid)
2 Power Status shutdown status output (24V during operation, 0V after shutdown)
3- Undefined
4- Undefined
5- Undefined
Lower row (main power supply) 6-24V negative pole (-)
7+24V positive pole (+)
8+battery positive pole (+, UPS optional)
9- Battery negative pole (-, UPS optional)
10+24V positive pole (+, redundant power supply)
Pin 7 and 10 are connected in parallel internally, allowing the use of dual core cables to share current and reduce the current carrying pressure on a single wire.
2.2 PC-ON and Power Status Collaborative Shutdown Logic - Core Engineering Points
The C63xx series does not have an independent power switch, and its on/off logic is achieved through the coordinated cooperation of PC-ON input signal and Power Status output signal:
Startup logic:
When the main power supply (pins 6/7 or 6/10) is connected to 24V, the industrial computer automatically starts without any additional trigger signal.
This means that as soon as the main power supply of the control cabinet is powered on, the industrial computer will start booting the operating system.
Shutdown logic (key feature):
Apply a 24V DC signal to PC-ON (pin 1) (e.g. through an external button or PLC output).
After the industrial computer detects that PC_SON is at a high level, it triggers the operating system to execute a secure shutdown process (equivalent to Windows' "Start → Shutdown").
After the operating system completes shutdown, the Power Status (pin 2) switches from 24V to 0V - this signal can be used to drive external contactors or relays.
After the external circuit detects that the Power Status is 0V, it can safely cut off the main power supply (disconnect the 24V power supply to pins 6/7), achieving a complete system power outage.
Engineering value:
This mechanism avoids data loss or file system damage caused by directly cutting off the power supply of the industrial computer.
The feedback signal from Power Status enables the upper PLC or control cabinet main contactor to accurately sense the completion time of shutdown, thereby achieving a fully automated process of "pressing the shutdown button → automatic system shutdown → automatic disconnection of the main power supply in the cabinet".
2.3 Assembly process of power connector (stress relief shell)
The 5-pin connector equipped with C63xx-0020 requires users to assemble it themselves, and the assembly of its Strain Relief Housing directly affects the reliability of the cable in vibration environments. Please follow the following procedure:
Step 1: Wire stripping and pin connection
The stripping length of the wire is 8-9mm.
Maximum allowable wire diameter: 1.5 mm ² (approximately AWG 16).
Insert the wire end into the 5-pin plug according to the pin definition and tighten the screw.
Step 2: Stress relief shell assembly
Thread the lacing cord into the reserved slot on the lower half of the stress relief shell.
Insert the pre wired 5-pin plug into the lower half of the casing.
Tighten the cable tie and cut off any excess plastic ends to firmly secure the cable to the casing.
Buckle the upper part of the shell onto the lower part, and hear a "click" sound to indicate that it is locked in place.
Key engineering constraints:
When the length of the power cable is long, it is necessary to calculate the voltage drop - to ensure that the voltage reaching the power plug of the industrial computer is not less than 22V (the lower limit allowed for rated 24V). Using a 1.5mm ² cable can minimize the voltage drop during long-distance transmission.
An external 24V power supply must be equipped with a 16A fuse as line protection.

Chapter 3: Mechanical Installation and Heat Dissipation Space Requirements
3.1 Preparation for installation of control cabinet
The C63xx series industrial control computer is fixed inside the control cabinet through a mounting plate. Depending on the model, the mounting plate can be installed on the rear wall or right side wall (see Chapter 7 for specific location in the assembly dimension diagram).
Before installation, it is necessary to confirm:
The control cabinet wall has been machined with four fixed bolt holes according to the assembly dimension diagram.
At least 50mm of ventilation space should be reserved above and below - for fanless models (C6320/C6325/C6335), natural convection heat dissipation relies entirely on air circulation above and below.
The ventilation duct must not be obstructed, otherwise it may cause equipment overheating, frequency reduction or damage.
3.2 Grounding specifications
There is a dedicated grounding point on the top of the industrial computer chassis. During installation, a low impedance connection must be established:
Use copper braided tape or a wire with sufficient cross-sectional area to connect the grounding point to the central grounding point of the control cabinet.
The purpose of grounding connection is to discharge common mode interference coupled by external power lines and signal lines, ensuring that EMC performance meets the requirements of EN 61000-6-2/6-4.
Chapter 4: Interface Layout and Peripheral Connection
All interfaces of the C63xx-0020 series are located at the top of the chassis, making it easy to exit from the top of the cabinet.
4.1 List of onboard interfaces
USB 1/USB 2: Two USB 2.0 interfaces, mainly used for connecting CP68xx/CP78xx control panels (touch screen data and keyboard communication).
USB 3: The third USB 2.0 interface is used to connect other peripheral devices such as USB drives, code readers, keyboard/mouse receivers.
Network (LAN1/LAN2): Two 10/100/1000BASE-T RJ45 Ethernet interfaces - one can be dedicated to EtherCAT real-time communication, and the other is used for upper computer network connection or factory network access.
DVI-II interface: used to connect CP68xx/CP78xx control panel (video signal). To connect a VGA monitor, an adapter is required:
C9900-Z411: DVI-I-VGA plug adapter
C9900-Z413: DVI-I-TVI and VGA Branch Cable (15cm)
RS232 COM2: 9-pin Sub-D serial port, used to connect old serial devices.
4.2 Matching advantages with CP68xx/CP78xx control panel
The original text emphasizes that the C63xx-0020 is an ideal combination with the DVI/USB control panel (CP68xx or CP78xx). The advantage of this pairing is that:
Single cable video+USB: DVI transmits display signals, USB transmits touch screen and keyboard data, two cables can complete panel connection.
Remote deployment of panels: If the panel is far away from the industrial computer (exceeding the USB 5-meter limit), it can be extended to 50 meters through CAT5 Ethernet cable in conjunction with the CU8800 USB extender series.

Chapter 5: UPS Software Components and Battery Pack Configuration
5.1 Integrated UPS Options (C9900-U330)
C63xx-0020 can be equipped with C9900-U330 battery pack for uninterrupted power supply (UPS). The battery pack is a 3.4 Ah VRLA-AGM sealed lead-acid battery, installed on a DIN rail, with a working temperature of 0-50 ° C.
Critical safety warning:
Only C9900-U330 battery pack is allowed! There is a risk of explosion when using other types of battery packs!
5.2 Installation of UPS software components
The UPS function requires the industrial computer to install the corresponding UPS driver software and UPS driver program:
If the operating system is pre installed at the factory, the software is already pre installed.
If you need to install it yourself, execute the Beckhoff UPS vx. xx. xx. exe file on the driver CD (C9900-S700 xxxx), and the program will automatically boot the installation.
After installation, detailed help files (including configuration instructions and troubleshooting guidance) can be accessed through the Start menu>Programs>Beckhoff>UPS software components.
Chapter 6: Quick Troubleshooting Checklist
Possible causes and troubleshooting measures for fault phenomena
After connecting the power supply, the industrial computer showed no response. The 24V power supply was not connected/the fuse was blown/other faults occurred. 1. Measure whether the voltage between pins 6-7 of the power plug is within the range of 22-30V.
2. Check if the external 16A fuse is blown.
If the voltage is normal but there is still no response, contact Beckhoff Service.
The system is unable to complete the boot process (stuck in the BIOS or Windows boot interface). The floppy disk/disc is left in the drive/BIOS settings are incorrect. 1. Remove all media from the drive and press any key to continue.
2. Enter BIOS to check the boot sequence and other key settings.
If it still cannot be restored, contact Beckhoff Service.
The system has started but the control panel does not display. The DVI cable is loose/the panel is not powered on/USB communication is abnormal. 1. Check if the locking screw of the DVI connector is in place.
2. Confirm that the 24V power supply of the CP68xx/CP78xx panel is normal.
3. Check if the USB cable is connected to the USB1 or USB2 interface (panel specific port).
After pressing the shutdown button, the system does not automatically power off. PC-ON signal has not been received/Power Status is not connected to the main contactor. 1. Measure whether pin 1 (PC-ON) receives a 24V signal.
2. Check if pin 2 (Power Status) jumps from 24V to 0V after the system shuts down.
3. If there is no output from Power Status, check if the UPS software components are installed correctly.
The fanless model (C6320/C6325/C6335) crashes after running for a period of time due to poor heat dissipation/excessive ambient temperature. 1. Check if the ventilation space of 50mm above and below the equipment is blocked.
2. Measure whether the ambient temperature inside the control cabinet exceeds 55 ° C.
3. Clean the dust on the surface of the heat dissipation fins (use a soft bristled brush after power off).
Chapter 7: Summary of Key Points for Selection Decision
Reasons for recommending models based on scene requirements
Dust/humid environment, difficult maintenance C6325-0020 (no fan+flash drive) The whole machine has no mechanical moving parts, maintenance free, and the best seismic resistance
Compact interior space, no optical drive required C6320-0020 minimum width (93mm), no fan, suitable for small control cabinets
A CD drive is required, but the temperature inside the cabinet is controllable. C6330-0020 or C6350-0020 with a fan has higher heat dissipation efficiency and includes a Slim Line CD-ROM
A CD drive is required, but there is a lot of dust in the environment. C6335-0020 without fan+CD drive combination, balancing heat dissipation and functional integrity
The C6325-0020+C9900-U330 UPS flash drive has extremely high requirements for data security and is not afraid of vibration. The UPS ensures that data can be safely stored in the event of a power outage
