Welcome to EMAlertÒ , the last line of defense against electromagnetic interference (EMI).
No matter how well you protect your important equipment against harmful effects of electromagnetic interference, EMI still can penetrate shielding barriers and cause equipment malfunction and failure. At best, EMI may cause intermittent disruption of operation and hundreds of thousand dollars in attempts to diagnose the problem (infamous NFF - No Fault Found condition in Aviation); at worst, it may lead to loss of human lives. There are numerous documented cases of fatalities due to EMI in aviation and medical fields, as well as in many others. As an example, studies found that traffic lights are susceptible to EMI and can cause severe traffic problems and accidents. Should you wand to know more how EMI can affect operation of critical equipment, please check our EMC links page.
EMAlert modules installed inside of critical equipment continuously monitor emission level, as well as its amplitude modulation since the latter can cause more damage that steady field. Until the level of EMI exceeds preset level (user-set), EMAlert modules are just passive observers. The moment the interference exceeds the preset level, however, EMAlert module sends signal that the EM EventTM has occurred and then begins to probe the host equipment by sending pulses every 3ms. The host equipment is supposed to respond with similar pulses if it continues to function properly. Should the host fail to respond, EMAlert issues Equipment Failure signal and, if desired, attempts to reset the host.

Up to 10 EMAlert modules can be networked together to provide just single interface to the host while monitoring both radiated and conducted emission in multiple points.

Each EMAlert module generates DC voltage that is a function of the field strength. This signal, along with EM Event signal, could be used by a data logging system to log EMI history that can be extremely helpful for failure diagnostics. In order to perform just this function, EMAlert modules do not need to be connected to the host in any way.

EMAlert modules can be either board or chassis mounted and monitor both radiated and conducted emission.
Click here to view detailed datasheet in Adobe Acrobat format (204KB)

Click here to view application notes for EMAlert in Adobe Acrobat Format (1.36MB)

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Aware, EMAlert, EM Event, EMEye and ScanEM are trademarks of Credence Technologies, Inc.
Products are covered by patents or are patent pending. All specifications are subject to change without notice.