IO configuration in TwinCAT

Configuration of EtherCAT P via TwinCAT

 

EtherCAT P tab

From TwinCAT 3 Build 4020 TwinCAT has the tab “EtherCAT P”. This tab contains a planning tool to calculate voltages, currents and cable lengths of EtherCAT P system. The figure below shows the tab EtherCAT P when no device is connected to the junction device (A).

 
Tab EtherCAT P: No device connected to junction device

If a device is connected to the junction device (A), you can set the cross-section and the length of the EtherCAT P cable in the Tab „EtherCAT P“ of the device. See figure below, B).

 
Tab EtherCAT P: One device connected to junction device

Are three devices connected to the three ports of the junction device (A), they are displayed as shown in the figure below.

 
Tab EtherCAT P: Three devices connected to junction device
 
Wire Gauge
Selection of the wire cross-sectional area of the cable which is to be used
AWG 22 = 0.34 mm²
AWG 24 = 0.22 mm²
Length (m)
Indication of the cable length which is to be used
Check EtherCAT P System
At least one device is connected to the controller, the connected EtherCAT P system can be checked
Type
Listing of two voltages: Box supply US, Auxiliary voltage UP
Actual Voltage (V)
The respective voltage at which the system is powered, can be entered manually. The default setting is 24.00 V.
Min Voltage (V)
The minimum voltage is preset by the device and described in the ESI file. The EtherCAT P system is to be interpreted after this voltage. It is valid not to fall short this voltage.
Load (A)
The total consumption of the connected sensors / actuators at the device can be specified here,e.g. 100 mA.
Load Type
The characteristic of the load which is connected to the devices can be selected here. Which of the three options is right for the connected load (Sw regulator, LDO, Resistor), must be taken from the datasheet. In case of doubt please select the default value "Sw Regulator".
Sw Regulator: Switching regulators, consume more energy and therefore require an efficient power supply.
LDO: Low drop voltage regulator, the energy demand is often small and the heat dissipation is not a problem, e.g. proximity sensor.
Resistor: electronic, passive components e.g. relay, coil
 
 
 
 
 

If you click on the button “Check EtherCAT P System”, all devices that are attached to your TwinCAT tree are listed as shown in the following figure.

 
Check EtherCAT P System
 
 
No.
The automatically assigned number of the device according to its position in the EtherCAT P strand.
 
Name
Designation of the device in TwinCAT.
 
Previous
Number of the previous device in the EtherCAT P strand and the output port used (A/B/C/D).
 
Us (V), Up (V)
Supply voltage which is present at the input of the device. For device No. 1 You can enter the voltages manually.
 
Sum Is(A), Sum Ip(A)
Sum currents of the supply voltages at the input of the device.
 
Us Load, Up Load
Enter here the total load at the IO ports of the device here.
The unit of this value is set by the choice of "Us Load Type" and "Up Load Type".
 
Us Load Type, Up Load Type
Choose here the characteristic of the load, which is connected to the IO ports of the device.
 
Cable Length (m)
Enter here the length of the EtherCAT P cable, which is connected to the input of the device.
 
Wire Gauge
Choose here the wire cross-section of the EtherCAT P cable, which is connected to the input of the device.
AWG 22 = 0,34 mm²
AWG 24 = 0,22 mm²
 
 
 

Example with problem case and troubleshooting

The following figure shows the planning of the EtherCAT P system without a problem. All voltages in the column “Supply Voltage (V)” are highlighted in green.

 
Check EtherCAT P system without problem

The following figure shows the planning of the EtherCAT P system with a problem. The “Supply Voltage (V)” of Box 5 drops below the “Min. voltage (V)”. The corresponding field is highlighted in red. The error occurs because longer cables (adjustable in Cable Length (m)) and also AWG 24 instead of AWG 22 cables (adjustable in Wire Gauge) be used.

 
Check EtherCAT P System with problem

This area offers the following three options to adjust the system so that there is no error:

Provide a higher voltage: There are max. 28.8 V possible.
Use an EtherCAT P cable with a larger wire cross sectional area (AWG 22 instead of AWG 24).
New voltage feed.
 
 

Topology of the EtherCAT P system

You can view the topology of your EtherCAT P system, as described in the figure below:

 
1.
In the Click on "Device 1 (EtherCAT)" in the "Solution Explorer"
2.
Click on the "EtherCAT" tab
3.
Click on the "Topology" button
The topology of your EtherCAT P system is displayed.
 
 
Example: Three devices are connected to the three ports of the distributor device.