: Knowledgebase

Maximum Lightning Protection (MLP) Surge Protectors

The Phone Company provides basic Lightning Protection at the entrance to a building.

Basic protection prevents an old style non-electronic telephone along with the wiring in the building from burning up. This basic protection lets so much voltage and current through that anything electronic will likely get blown up.

Our Maximum Lightning Protection™ modules are engineered to protect specific types of telephone and data equipment attached to phone lines, based on the type of phone line, and the equipment attached.

Our Maximum Lightning Protection™ modules are Solid State, automatically clamp large surges down to 10-15 volts, and have self-resetting Over Current Protection to handle up to twice the damaging current of any other Lightning Protector.

We call it Maximum Lightning Protection™ because this is the best (affordable) lightning protection money can buy...

You won't find anything better on the market short of using an expensive device that converts to fiber and back (lightning will never get past fiber!)

While the Phone Company has a single type of protector they install on every line (called primary protection... see an explanation below*), if you have electronic phone equipment you also need the Secondary Protection offered by our Maximum Lightning Protection™ modules.

The biggest risk of lightning damage? An OPX (Off Premise Extension), where an electronic or analog station port leaves a building... even for 5 feet!

If you have OPXs leaving a building going to another building, you ABSOLUTELY need the correct Maximum Lightning Protection™ module for the type of equipment on the line.

It doesn't matter whether the cable goes 10 feet or 10 miles, whether it's in conduit or just buried in the ground 2 inches or 2 yards deep, lightning will find that cable and damage your expensive electronic equipment. Conduit will not prevent lightning from getting to a cable running outside a building.

Maximum Lightning Protection™ Features:

  • Dual Stage Protection... for Over Current and Over Voltage, that resets Automatically!
  • Solid State Circuit automatically clamps surges to 10-15 volts.
  • Our MLP-270 Telephone Line Protector Module handles up to twice the current of any other Lightning Protector!
  • Electronic Resettable Fuse opens above 150ma, providing protection against AC power line crosses, and closes automatically.
  • Our T1, T3 and 100-BaseT Protectors stop damaging common mode surges that others don't!
  • Each Protector has Test Points to allow a quick check for dial tone with a Butt-set.
  • Our Ground Bus allows insertion and removal of one Protector on a 66 Block, without removing other Protectors. Once seated on the 66 block, just tighten the ground screw. You don't have to remove the screw, except to install a Ground Lug on the last Protector.
  • Our Test Shoe lets you test a line by removing only one Protector (since you'd have to remove a couple of Protectors from working lines to get your Butt-set clips directly onto the block). A Busy Light on the Test Shoe lets you know when the line is free, so you can push the button to open the line for testing.

Lightning Protectors won't do anything without a GOOD GROUND!

When used with our Maximum Lightning Protection™ Modules, the ground diverts high voltage from lightning or a surge to the earth, instead of letting it get to the electronic equipment.

In the old days, a cold-water pipe was considered the best ground available. Today, you should never use a cold-water pipe for a ground since there is so much PVC (non-conductive) pipe out there.

The Phone Company ground at the NI (Network Interface) is not considered a good ground. It may not even be attached to anything!

The best ground to use today is the electrical panel, which should be grounded to a ground rod driven into the earth just outside the wall where the panel is located. Be sure to check that there is a ground on the outlets with an AC Outlet Tester!

NOTE: An AC Outlet Tester will tell you if the outlet is wired correctly and if a ground is present, but not the quality of the ground. You should look to make sure the AC power panel is physically wired to the ground rod. If you're not sure, special testers are available that will verify the quality of a ground.

IMPORTANT! In rocky and sandy areas (like on a mountain or beach) you'll need a professional to come out and install the best ground possible. A regular ground rod won't give you a good ground in rock, gravel, clay, or sand. This applies to both voice and data lightning protectors and AC powered devices with AC surge protectors.

Our Ground Plug with 10' Ground Wire will save you a ton of time running a separate ground to the power panel. Just plug it into a (properly grounded) AC outlet, run the wire over to the 66 Block, and attach the wire to the Ground Lug that's included with the Ground Bus.

See our Electrical Grounding Tech Bulletin for more information on proper grounding.

Never let a pair into or out of a building without Maximum Lightning Protection™!

Phone systems have no protection built-in for stations, so almost any surge will knock out an expensive analog or digital station card. Phone system manufacturers know that the CO lines are coming from outside the building, so they build basic lightning protection into the trunk cards. They figure only a very small percentage of stations will leave a building, so they build no protection into stations (since all of their customers would have to pay for the very small percentage of customers using OPXs).

Don't even think about running a station outside of a building, even for 5 feet, without the correct Maximum Lightning Protector™.

How do you know if a Lightning Protector has worked?

Lightning or Surge Protection (AC or telephone) has worked if the equipment isn't blown up after a storm!

If the equipment is damaged, the Protector(s) should be tested to see if a component is damaged.

If the equipment is damaged, and the Protector isn't damaged, that means there was a bad ground (or no ground) attached to the Protector. A Protector should fail shorted to ground before allowing damaging voltage or current to get to the equipment it's protecting.

Unlike a Protector with a "Sneak Fuse", our Maximum Lightning Protectors™ have a solid-state self-resetting electronic fuse that prevents service calls in all but the worst lightning storms (where the whole Protector will be blown-up, saving the telephone equipment).

So, what's the difference between Primary and Secondary Lightning Protection?

Primary Protection is normally a carbon or gas tube protector with a good ground (usually installed by the phone company) that diverts high voltages of over 500V or so to ground, in 100ns or more. Secondary Protection will divert the high voltage surge to ground at a much lower voltage, much faster, and will also usually add over current protection.

NOTE: Nothing will stop a direct hit from lightning. A direct hit (or even a hit in the general area) is so powerful that it can blow-up battery-operated devices like smoke detectors. Regular business insurance generally doesn't cover telephone systems that are damaged by surges, flood, or water leaks. It's not a bad idea to check out EDP (Electronic Data Policy) insurance, which will cover you for this type of damage to your computers as well as telephone equipment (subject to a deductible).

So far, every direct hit has resulted in the Maximum Lightning Protector™ turning into a glob of bad smelling plastic. It gave its life to protect the equipment, but it failed shorted to ground (so the equipment can't be damaged by further lightning hits) and will need to be replaced.

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