Lightning arrestor and surge protector wiring

rhensel · January 4, 2011, 2:25am

I went to Home Depot and Lowe’s today to buy these items just so I can have the manufactures directions on how to install them. I see many of them wired directly to the main lugs. I do not think that is proper. Can anyone direct me to the place where I can find the wiring directions to these items. I used search engines and could not find the wiring diagram or instructions. Thanks in advance for the help.

wwarner · January 4, 2011, 3:07am

Leviton 51120-x whole house surge protector:

wwarner · January 4, 2011, 3:43am

Delta lightning arrestors…
http://www.deltala.com/installa.htm

rhensel · January 4, 2011, 3:54am

From what I can see surge protectors cannot be attached to the main lugs and the lighting arrestor is to be attached to the main lugs.

I guess I will have to look up on a case by case basis. Thanks for the info, it was very kind of you.

rmeier2 · January 4, 2011, 9:59am

This section, from the 2008 NEC, would prohibit double tapping the mains in most cases since those lugs are typically rated for only one conductor.

110.14 Electrical Connections.
Because of different characteristics of dissimilar metals, devices such as pressure terminal or pressure splicing connectors and soldering lugs shall be identified for the material of the conductor and shall be properly installed and used. Conductors of dissimilar metals shall not be intermixed in a terminal or splicing connector where physical contact occurs between dissimilar conductors (such as copper and aluminum, copper and copper-clad aluminum, or aluminum and copper-clad aluminum), unless the device is identified for the purpose and conditions of use. Materials such as solder, fluxes, inhibitors, and compounds, where employed, shall be suitable for the use and shall be of a type that will not adversely affect the conductors, installation, or equipment.
FPN: Many terminations and equipment are marked with a tightening torque.
(A) Terminals. Connection of conductors to terminal parts shall ensure a thoroughly good connection without damaging the conductors and shall be made by means of pressure connectors (including set-screw type), solder lugs, or splices to flexible leads. Connection by means of wire-binding screws or studs and nuts that have upturned lugs or the equivalent shall be permitted for 10 AWG or smaller conductors.
Terminals for more than one conductor and terminals used to connect aluminum shall be so identified.

rsole · January 6, 2011, 8:39pm

It used to be common around here that the arrestor was attached to the lugs on the main disconnect. In all new installations they are now connecting them to a circuit breaker.

gliebig · February 12, 2012, 3:12pm

I ran across this yesterday. Sorry the writing on the device is not very legible. I can’t imagine this thing even working. A plastic device on the outside of the service panel with 3 conductors tapped directly to a 200 amp main breaker. Are you kidding me? Please tell me why I should be convinced this works.

dedwards · February 12, 2012, 6:46pm

This does NOT address you question but around here, the local power company will install these devices on your home to provide those protections for $4.95 a month. The other good thing is they will then put you into their system for the lowest rates…all the time. It will installed correctly and you get off the highest rates and into a lower cost per kilowatt rate. I would surprised they did not have something like that across the State as energy conscience as FL is. They will also do a FREE energy audit, install a new thermostat and some other energy saving features. They do all kinds of wacky things here…buy any old refrigerators, freezers to keep them out of the land fills, will pay for a new water heater if you currently have gas and will convert over…to name a few. There may be a similar program in your area.