From Friday, April 19th (11:00 PM CDT) through Saturday, April 20th (2:00 PM CDT), 2024, will undergo system upgrades that may result in temporary service interruption.

We appreciate your patience as we improve our online experience.

Differences Between EtherCAT Slaves NI 9144 and NI 9145


This article explains the differences between the NI 9144 and the NI 9145.


The NI 9145 is a replacement for the NI 9144 and the core functionalities and the appearance remain the same.

  • The NI 9145 is only supported in EtherCAT 16.1 and later. The NI 9144 is also supported in earlier versions of the driver.
  • The NI 9145 has more memory and FPGA resource from a hardware perspective.
  • On the software side, the NI 9145's core functionalities are same as the NI 9144. You can set up and use the NI 9145 with exactly the same procedures as the NI 9144.


However, with upgrading the hardware, you will get the performance improvement mentioned below with the NI 9145:

PDO (Process Data Object) size improvement

EtherCAT ChassisPDO InputPDO Output
NI 9144512 Bytes512 Bytes
NI 91457500 Bytes7500 Bytes


HSI (High Speed Interface) module support

The NI 9144 only support HSI modules on the first 4 slots; however, the NI 9145 can support HSI modules on all 8 slots.

EtherCAT ChassisHSI Support
NI 9144Slot 1-4
NI 9145Slot 1-8


Was this information helpful?