Surge SuppressorsProtection for Electronic Devices
Delicate electronic devices are subject to damage by power line transients and/or lightning-induced overvoltages, as well as discharges of static electricity. Presently, there are three basic categories of industrial devices for protection:
Metal Oxide Varistors(MOV's)
These begin to conduct at their "breakdown voltage" which increases with increasing current. The implication of this is that the expected limitation at a certain voltage is easily exceeded. Also, a wearout characteristic that is inherent in MOV's limits their useful life considerably.
TransZorbs start to conduct at their "breakdown voltage" - much like MOV's - but are more stable in maintaining this voltage limiting feature than an MOV. Another important difference is that unlike MOV's, there is no significant wearout characteristic.
A SIDACtor begins to conduct at its "breakdown voltage" The key difference is that it switches into a "crowbar state" as the voltage increases. This is like a total short circuit of the incoming transient, which results in complete protection within nanoseconds. This short-circuit behaviour may result in severe current overloads that must be limited and fused.
Electrolab utilizes SIDACtors as the ultimate limiting device in all surge suppression and has a wide list of products available to cover various applications and line voltages. Since a severe transient can damage the protective device, Electrolab offers red LEDs as an indicator of the status of the suppressor.