Generally, 4-20 mA vibration monitoring is used for equipment that ought to be monitored for vibration, but where access or infrequent servicing is an issue. The iT modules present options for installing vibration monitoring. The transmitter allows a 4-20 mA signal to be used for simplified monitoring, while preserving access to the full bandwidth of an accelerometer for detailed vibration spectrum analysis.
The iT Alarm allows for local alarm and shutdown capability. The fact that the IT401 can be used with either the iT Transmitter or any 4-20 mA sensor offers users greater flexibility. A system can be built for monitoring that utilizes both vibration and process variables for alarming.
Many plant process computers have already utilized all available analog input channels. Adding even just a couple more analog channels may be prohibitively expensive. With the iT Alarm, the local processing offered by a combination of an iT Transmitter with an iT Alarm allows the use of spare digital inputs to the plant process computer. Frequently, there are many unused digital inputs when the analog inputs are full.