[Amps] MOVs

[Jim Brown]

Because MOV's conduct surge currents onto ground, and the IR (and IZ) 
drop raises the potential of the chassis. When the "protected" equipment 
has a low voltage connection to other equipment powered and/or grounded 
at another point, the difference between one chassis and the other often 
fries the interface circuitry.

I've seen many well-documented examples of this with audio systems, and 
with computers connected by wired Ethernet, no radios anywhere around.  
The sharp guys in pro audio stopped using MOVs at least 20 years ago.

73, Jim K9YC

On 1/22/2014 10:11 PM, Jim W7RY wrote:
> Why?
>
> On 1/22/2014 9:59 PM, Jim Brown wrote:
>> On 1/22/2014 8:40 PM, Gary "Joe" Mayfield wrote:
>>> What are folks thoughts
>>> about MOVs on the primary side of the transformer?
>>
>> Bad idea. ANY MOV on branch circuits is a bad idea.