BECKHOFF CX2100-0014 Power Module Guide

Power wiring and UL requirements

3.1 Definition of Wiring Terminals

The right power terminal block of CX2100-0014 adopts a spring crimping type and is divided into two groups:

Upper row (Us): marked with "24 V" and "0 V", providing power to the CPU module and bus (K-bus/E-bus). This is the core power supply of the entire system.

Bottom row (Up): Three terminals marked with "+" (actually+24 V, 0 V, ±? Table 3 in the manual shows: power contact number 9 "+24 V", power contact number 10 "0 V", and spring terminal number 12- actually used to supply power to the bus terminal's power contact, electrically isolated from Us.

Wiring specifications: The cross-sectional area of the wire is 0.5~2.5 mm ² (AWG 20~14), and the stripping length is 8~9 mm. Insert a straight screwdriver into the square hole, press down the spring, insert the wire into the circular hole, and pull out the screwdriver to lock it.

3.2 Power Supply Logic and Voltage Requirements

Us and Up can come from the same 24V power supply or be supplied separately, but they must be grounded together (connected to the same potential at 0V). According to EN 60204-1:2006 PELV requirements, the 0 V end of the power supply must be connected to the protective conductor system (grounding bar inside the control cabinet).

After power on, two green LEDs should light up:

Us 24V LED: CPU and bus power supply are normal

Up 24V LED: Power contact supply is normal

If any LED does not light up, check the corresponding circuit voltage (at least 22V is required, as a -15% drop is allowed).

3.3 UL Compliance Precautions

For UL certified environments (see UL mark on module nameplate), the following must be met:

The power supply voltage source is isolated 24 V DC with a maximum of 4 A fuse (compliant with UL248 standard), or the power supply is NEC Class 2.

Do not use two NEC Class 2 power supplies in series or parallel.

K-bus diagnosis and detailed explanation of fault codes

When CX2100-0014 is connected to traditional bus terminals (KL series), it operates in K-bus mode. The diagnostic LED "K-BUS RUN" is always green, indicating normal operation; The red flashing of "K-BUS ERR" indicates an error. Flashing mode rules:

Quick flashing: Error sequence begins

First slow sequence (number of pulses): Error code

Temporarily extinguished

Second slow sequence (number of pulses): incorrect parameter (usually indicating the location of the faulty terminal)

Common Error Code Table

Error code (pulse count), error parameter meaning, handling measures

Continuous flashing (no code) - EMC interference check for power spikes, improve grounding, add filters; Re powering on may locate the fault

30 K-bus command error: bus terminal not inserted or damaged; Using binary method to remove terminals one by one and search for fault points

Check if the first terminal is properly plugged in when the data is disconnected (immediately after the power module); Is there a KL9010 terminal at the end

4 n (>0) Check if the (n+1) th terminal is reliably connected after the nth terminal is disconnected

5. Communication error with the nth terminal register. Replace the nth terminal

6 0 initialization error, replace embedded PC

6 1 or 8 internal data error hardware reset (power off and power on again)

7 0 Process Data Length Mismatch Check if TwinCAT Configuration is Consistent with Actual Terminals

Important: Even if the root cause of certain errors has been eliminated, the K-BUS ERR will continue to flash. At this time, the 24V power supply to the power module must be disconnected (only the Us) and then powered back on to clear the flashing.

Diagnosing K-bus status through PLC program

In TwinCAT, the State variable (address IB2, byte type) of the bus coupler provides more diagnostic information. The meanings of this variable are:

Bit meaning

0 K-bus error

1. Terminal configuration changes after self startup

2 Process image length mismatch

8 No valid input

9 K-bus input update incomplete

10 K-bus output update incomplete

11 watchdog error

15 Asynchronous K-bus function activation (such as reset)

If a K-bus error (State<>0) is detected, the IOF_DeviceReset function block (from the TcIoFunctions library) can be called to attempt to reset the bus. It is recommended to check State. 0 after each startup or hot reset, and if it is 1, trigger a rescan configuration.

E-bus diagnosis and LED indication

When connecting the EtherCAT terminal (EL series), the module automatically switches to E-bus mode. Diagnostic LED meaning:

Us 24V: Green constant light=CPU and bus power supply are normal

Up 24V: Green constant light=Power supply contacts are supplying power normally

L/A: Off=E-bus not connected; Always on=Connected but without data; Flashing=Data transmission and reception in progress

There is no dedicated "ERR" LED in E-bus mode, and error messages are displayed through TwinCAT's CoE (CAN over EtherCAT) directory or state machine status. If the E-bus communication is interrupted, first check the physical connection (the E-bus is transmitted through the contacts on the terminal side without the need for external cables), and confirm that all terminals are correctly locked and not exceeding the maximum number (65534).