Chapter 1 Getting Started
NI USB-621x User Manual 1-4 ni.com
USB Cable Strain Relief
You can provide strain relief for the USB cable in the following ways:
• Cable Strain Relief Groove Method—
(USB-621x Screw Terminal/Mass 
Termination Devices)
 Press the USB cable into one of the two grooves 
on the underside of the USB-621x. Choose the USB cable groove that 
matches your USB cable size, as shown in Figure 1-2a. 
• Zip Tie Method—
(USB-621x Screw Terminal/Mass Termination Devices) 
Thread a zip tie through the zip tie bar on the underside of the 
USB-621x and tighten around the USB cable, as shown in Figure 1-2b.
Figure 1-2.  USB Cable Strain Relief Options on USB-621x Screw Terminal/Mass 
Termination Devices
1 USB Cable Strain Relief Groove (Large)
2 USB Cable Strain Relief Groove (Small)
3 USB Cable
4 Zip Tie
5 Zip Tie Bar
6 Stacking Groove