In recent years, all major suppliers of shaker vibration controllers and data acquisition products have started to adopt Ethernet connectivity. Vibration Research, Data Physics, B&K, m+p, and of course, Crystal Instruments now all utilize Ethernet connections in their controllers and data acquisition (DAQ) products. USB connection is becoming nearly obsolete.
Ethernet has many advantages over USB. Some advantages are:
- Ethernet cables can be as long as hundreds of meters while USB connections are limited to a few meters. In other words, if a controller is using a USB connection, the distance between the PC and the controller is no more than a few meters.
- Ethernet is “floating” against the ground. This greatly reduces the ground-loop problem in the vibration controller installation
- Ethernet is usually faster, and does not require a software driver
- It is easier to connect multiple hardware units together using Ethernet
The major difference between CI and other Ethernet based controller products is that CI uses IEEE 1588 PTP to synchronize the sampling clock on different hardware units. The other products on the market usually require an additional trigger bus besides the Ethernet cable. The beauty of IEEE 1588 PTP is that all time synchronization is conducted on the same Ethernet cable that is used for network communication.