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NEMA, ANSI, BSI, EEI, IES, EPA, UL, CSA, IEEE, FAA, FCC, IDA and PUC all
exert influence on how photocontrols are made and used.
5.1 ANSI
ANSI is the most widely recognized standards group for utility equipment
in North America. ANSI C136.10 (or C136.24 if you are using button controls)
should be the starting point for all utility photocontrol standards. When
you use it, remember they are compromise standards setting forth only
minimum requirements.
The ANSI C136 committee meets twice a year to write and review all Roadway
Lighting Standards.
5.2 IES (Illuminating Engineering Society)
The IES (Illuminating Engineering Society) Roadway Committee has written
DG-13 design guide for specifying photocontrols. Although not a standard,
the IES document has received wide circulation. It is a lengthy document
that covers a multitude of items. For example, the IES document suggests
a higher turn-ON level of 2.6 footcandles (27.9 lux) to account for HID
warm up time. It also suggests electronic controls with low OFF/ON ratios.
5.3 Green Lights
The U.S. government's EPA Green Lights Program supports lighting upgrades
that make technical and economic sense. A recent Green Lights report documented
the success story of a mid-Atlantic utility's switch to better quality
photocontrols. The utility saved significant maintenance dollars, reduced
energy consumption, reduced emissions, reduced total expenditure on photocontrols
and made the customers happy. Reprints are available from DTL.
5.4 International Dark Sky Association (IDA)
The IDA is very concerned about unneeded light going upward. They also
champion the cause of reducing light trespass and light pollution. Using
controls that are only on for the first half of the night (Part Night
controls like the DPN124-2.6-TMGN) may reduce concerns about light pollution.
5.5 BSI
The British Standards Institute requires that controls face upward with
pointed top covers. This is different than the ANSI standard that requires
north facing controls. Also, BSI wants the turn-ON level at 6.5 footcandles
(70 lux) instead of the ANSI recommended 1.5 footcandles ( 16 lux).
5.6 NEMA and IEEE
These are the National Electrical Manufacturers Association and the Institute
of Electrical and Electronic Engineers. Both groups support ANSI committees
that write Roadway Lighting Standards. The IEEE also sponsors national
utility shows that include lighting products.
5.7 UL
Underwriters Laboratories has standards for twistlock and button type
photocontrols. These are primarily safety standards. If you need controls
that meet UL standards, this must be clearly stated in your specifications.
For utilities, a UL listed control is not necessarily better for a specific
application than a non-UL product. It may be more expensive or lack some
needed features. Consult DTL for details. Preferred UL listed DTL model
is DUX124-12A.
5.8 CSA
The Canadian Standards Association has a standard for photocontrols.
Under NAFTA, UL and CSA will recognize each other as certified test laboratories.
5.9 FAA
The Federal Aviation Agency (USA) requires that towers near airports
be lighted. When photocontrols are used, these "obstruction light"
controls must be ON at 35 footcandles ( 375 lux) and OFF at 57 footcandles
(610 lux). These FAA controls are also useful for other applications that
demand that the light be ON very early in the evening.
5.10 FCC
The Federal Communications Commission (USA) regulates equipment that
might emit radio waves or cause radio interference. Properly designed
controls will not cause interference. New rules require controls with
microprocessors to be tested to FCC part 15.
5.11 PUC
In the United States, Public Utility Commissions (PUCs) in the USA regulate
the amount that utilities can charge customers for roadway lighting. PUCs
often specify how many annual burning hours a light will provide. Annual
burning hours are largely determined by the photocontrol, control orientation,
latitude, cloud cover and other factors. Thus, it is important that photocontrol
specifications for turn-ON and OFF be consistent with local PUC requirements.
For example: an electromechanical photocontrol made to ANSI standards
with a 2.0 footcandle turn-ON, a 10 footcandle turn-OFF, installed at
latitude 34° (e.g., Los Angeles, California) would yield about 4,342
burning hours per year. Most PUCs currently allow 4,000 to 4,200 burning
hours annually.
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