Surge protector/ power conditioner

Discussion in 'The Projects Forum' started by TheGreatGarbanzo, Apr 13, 2011.

  1. TheGreatGarbanzo

    Thread Starter New Member

    Apr 12, 2011
    Hello folks,

    I have recently aquired a surge protector /power conditioner from a friend of mine. This unit belonged to his mad scientist of an uncle who has recently passed on. We found 2 of these units while cleaning out the old guy's basement. One unit (mine) was missing two components from the surge protection part of it.

    The surge protector consists of:

    6 ea. MOV's (Z131 20 UL)
    2 ea. 220kΩ Resistors
    2 ea. Zener Diodes?(the missing components)

    I put a question mark by the Zener diodes because we are'nt sure. Somebody told us that they were Zener Diodes and then started talking about "clamping" and "avalanche" and "breakdown voltage" and alas I was lost.

    Does this make sense to you guys? If so would someone please tell me what I should buy in order to replace them.

    This is a 120v 60hz unit.

    Thank you

  2. SgtWookie


    Jul 17, 2007
    They might've been Neon indicators to show that power was on.
    One from hot to neutral with a 220k resistor in series to show the power was on.
    One from neutral to ground with a 220k resistor in series to indicate a wiring fault (Neutral should be within a few volts of ground).
  3. Wendy


    Mar 24, 2008
    A component called a MOV is used to absorb surges. It often dies in the process. While vaguely related to zener diodes, they are not zeners. It would probably be a lot cheaper to buy a new strip, they aren't that expensive, and new ones work while old ones may not (there are no visual symptoms).