[TowerTalk] control cables lightning protection

[Jim Lux]

On 6/24/11 11:17 AM, Grant Saviers wrote:
> Vishay makes Transient Voltage Suppressors (TVS) in clamp voltages from
> 10 volts to several hundred volts.  A common size can handle a 1500 watt
> surge.  They are very fast, I think faster than MOVs and have a sharper
> knee so the clamp voltage doesn't rise as much as MOVs with increased
> current.  Both unidirectional (diode in reverse) and bidirectional (for
> ac circuits) are available around $1 each qty 1.  For low power
> circuits, they are a good choice.  I think the construction is basically
> back to back heavy duty zeners for the bidirectional version, at a price
> far below stud mount zeners.
>
>

better yet, the semiconductor TVS devices don't wear out like MOVs do. 
with every transient, a MOV dies a bit and the leakage current increases.