Daisy Chaining
We are increasingly asked about daisy chaining - when powerstrips or current taps are plugged into each other in series. In particular we're regularly asked about plugging a powerstrip into a current tap.

The common questions are:

•   Should I do it?
•   Is it safe?
•   Does it comply with code?
•   Are there any legal implications?

This month we provide an overview of the issues with regards to daisy chaining.
Installation Example

ISSUE 1 - VOIDING CONNECTED DEVICE WARRANTIES

Connected Device Warranty
Selected manufacturers include a connected device warranty with their surge protected powerstrips. The intent is to differentiate better quality surge protected powerstrips from standard powerstrips.

Customers pay a premium to have this warranty to insure against damage to their (costly) amplifiers, TV's and electronics.

Manufacturers require their powerstrip to be directly connected to a branch outlet receptacle. Plugging a powerstrip into anything other than a branch outlet receptacle voids their connected device warranty.

Risks
A utility or EE program promoting a solution that specifically voids a connected device warranty exposes itself to litigation in the event that a consumers equipment is damaged by an electrical surge and the powerstrip manufacturer voids the connected device warranty due to incorrect installation.


ISSUE 2 - NON COMPLIANCE WITH UL

UL
UL XBYS. GuideInfo: Relocatable Power Taps states:

"Relocatable power taps are intended to be directly connected to a permanently installed branch circuit receptacle. Relocatable power taps are not intended to be series connected (daisy chained) to other relocatable power taps or to extension cords."

Plugging a powerstrip into a powerstrip or current tap is a breach of the UL guidelines and makes the installation non-compliant.

Risks
In the event of a fire, the homeowners insurance may be voided because equipment installed is in breach of UL guidelines and hence UL listing requirements.

A utility or EE program promoting a solution that specifically breaches UL safety guidelines may expose itself to litigation in the event of fire damage or injury in a customer's home.

ISSUE 3 - BREACH OF NATIONAL ELECTRIC CODE (NEC)

NEC
Plugging a powerstrip into a powerstrip or current tap is a direct violation of NEC� and OSHA Standards. Specifically NEC� Article 110.3(B), OSHA 29CFR 1910.303(b)(2), and 1926.403(b)(2) Installation and Use.

"Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling. These required instructions also include the requirements of the Nationally Recognised Testing Laboratory (NRTL) listing standard."

Underwriters Laboratories in product category XBYS which covers Relocatable Power Taps. Some Relocatable Power Taps also include Transient Voltage Surge Suppression (TVSS) under product category VZCA.

These TVSS's have been required to meet both UL standard requirements. As such they are also required to meet the "installation and use" characteristics of both categories/standards.

Risks
A utility or EE program promoting a solution that specifically voids the NEC Code or OSHA Standards may expose itself to considerable risk of litigation in the event of a fire, damage to property or injury to people.

ISSUE 4 - BREACH OF NATIONAL FIRE PROTECTION ASSOCIATION (NFPA) CODE

NFPA
The NFPA is based upon the International Fire Code and also requires compliance with the NEC.

Item 605.4.2 of the International Fire Code states "Relocatable power taps shall be directly installed to a permanently installed receptacle"

Risks
A utility or EE program promoting a solution that specifically voids the NFPA Code may expose itself to considerable risk of litigation in the event of a fire, damage to property or injury to people.

summary


Daisy chaining a powerstrip into another powerstrip or a powertap creates a number of serious problems and is highly problematic with regards to:

•   Electrical safety
•   Code compliance
•   Risk of litigation

Based on the issues identified we strongly recommend against the practice of daisy chaining of devices.

definitions

UL