Originally Posted by SoCalLandscapeMgmt
the TManufacturing unit is similar to the Control Tech board but probably not as heavy duty. They are using MOV protection which will give a limited amount of protection. The Control Tech boards are using chokes and gas discharge tubes. They can handle a little more abuse and have a much quicker reaction time than the MOV do. Of course as you pointed out nothing will save a controller from a direct of very near strike.
Actually MOV has a much faster reaction time and significantly lower clamping voltage than GDT. Their limited lifetime is their drawback, but quality MOV surge supressors can indicate whether or not they are still providing protection.
Regardless, all TVSS requires a quality ground source. The better the ground, the better the surge supressor will work. A 10 gauge solid copper ground is not overkill for a short run. Also, the ground wire should be "radiused" to its connections. That means that it should not have any sharp bends or kinks.