Hello: The question is not the energy handling capability, it is a matter of cost. You can purchase a TVS diode that has the same energy handling capability of the MOV, but the cost is much different. By the way, energy is not a good measure of the capability of a TVS component. The TransZorb has a lower clamping voltage than an MOV for the same peak pulse current and waveform. Therefore the calculated energy is lower in the TransZorb. Energy has nothing to do with the capability of the TVS device. It is also proven that the energy in the transient threat is not the energy dissipated in the TVS component, just ask any old timer even those at Harris. Dave
-----Original Message----- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of j...@aol.com Sent: Wednesday, June 19, 2002 9:51 AM To: robert_wil...@tirsys.com; mpet...@analogic.com; emc-p...@majordomo.ieee.org Subject: Re: Transient Voltage Suppressor - Europe approvals? In a message dated 6/19/2002, Bob Wilson writes: Transzorbs (or "TVS"s) are basically zener diodes that are rated for their energy absorption capability. Hello All: One thing to keep in mind is that the energy handling capability of a TransZorb is generally not very high compared to other devices such as gas tubes, MOV's, and sidactors. Michael, your original posting did not specify the intended application, but the reference to being "rated for mains voltage" makes me wonder if you are trying to protect from surges on an AC mains input. If so, I do not think that a TransZorb would have adequate energy handling capability. Joe Randolph Telecom Design Consultant Randolph Telecom, Inc. 781-721-2848 http://www.randolph-telecom.com
