What is Chatter?
Chatter is an event that can occur in response to shock vibration. It is detected in the mechanical relay or contactor of the device under test.
When a relay is subjected to a large shock event, such as an earthquake, the electromagnetic coil holding the contacts in the energized position and the spring tension holding the contacts in the de-energized position must be strong enough to withstand the force of the event. Otherwise, a contact chatter event can occur, leading to disconnection, wear, or damage.
Re-create chatter events in a laboratory setting by mounting the relay or contactor in the recommended position, simulating a shock test or earthquake, and monitoring the test. Any change in the contacts’ voltage will indicate a chatter event. You can then evaluate the results to determine the contacts’ effectiveness.
The VibrationVIEW Chatter Monitor software package detects contact chatter events. The software uses the RecorderVIEW package to record the test’s inputs. It then evaluates the recording to determine if a chatter event has occurred.
After evaluation, the software will display any detected events. You can evaluate each event and create a chatter report. Another option is to post-process already recorded files (.vfw).
With RecorderVIEW, there’s no need to buy extra equipment to collect data. The VR9500 and VR10500 controller hardware can connect to a notebook PC and function as a portable data acquisition system. Record field acceleration measurements directly to the PC’s hard drive. Plus, access all the features of the VR9500/VR10500, including:
- Low noise floor
- 24-bit resolution inputs
- Built-in accelerometer constant current supply
- TEDS transducer interface
- DC offset that allows a measurement to true DC with constant current type accelerometers
Then, use the VibrationVIEW software to set up and monitor vibration tests with the recorded data.
Earthquake Testing in VibrationVIEW
Chatter monitoring is of particular interest to technicians performing earthquake testing. Structures and equipment installed in seismically active regions must be designed to protect the operating equipment in the event of an earthquake. With the VR9500/VR10500, you can perform single/multi-axis earthquake tests that meet standards using an earthquake test template or user-defined time transient.
VibrationVIEW runs earthquake simulations with the User-Defined Transient option. There are two methods of creating an earthquake simulation: via template or import.
User-Defined Transient Webinar
Types of Chatter Events
A chatter event is typically characterized as a bounce or discontinuity. A discontinuity is a significant deviation from a monitored parameter. A bounce occurs when the normally open contact does not make a secure connection when the electromagnetic coil is energized. If the current draw overloads the contacts when the coil is energized, then a perpetual bounce cycle can start.