Using motors in wet and damp environments.
Jan 1, 1996,
These application tips and suggestions will help extend motor life in these hostile environments.If you have a motor application that involves operation...
Establishing an electrostatic discharge control program.
Dec 1, 1995, Knisley, Joseph R.
What is electrostatic discharge and how can it be controlled to prevent damage to micro electronic components?Electrostatic discharge (ESD) can cause...
Upgrading a plant outdoor substation.
Dec 1, 1995, Lawrie, Robert J.
Photo story reveals design and construction details of a substation expansion that combines new 15kV equipment with existing 5kV systems.Flexibility of...
Tamper-resistant receptacles: the rules have changed.
Nov 1, 1995, Currall, John
What tamper-resistant products are UL-listed and what test methods are used?Tamper-resistant receptacles are the only devices that are specifically tested...
What do electrical professionals really want?
Oct 1, 1995, DeDad, John A.
A few months ago, we had the opportunity to gather together a group of electrical professionals to speak their minds and vent their frustrations on the...
Service protection higher than ampacity
Sep 1, 1995, Stallcup, James G.
A lighting and appliance branch-circuit panelboard must have individual over-current protection. The overcurrent protection may be the fuses or circuit...
Controlling building noise with good electrical designs.
Sep 1, 1995, Knisley, Joseph R.
Depending on the space in question, the attention given to acoustical sound attenuation is as important as the location of power and communications outlets,...
Providing four megs of power to protect computers.
Aug 1, 1995, Bender, Gayland J.
Fast track design and construction, thorough testing, and adjustments as needed provide power assurance to client's data operations.A strong concern for...
Multiple generators provide power for peak shaving/emergency systems.
Aug 1, 1995, Lawrie, Robert J.
Modular 4160V generators slash $1 million off annual electric bills and assure emergency power. Versatile monitoring, control, and PLC systems integrate...
Horsepower designations on appliances.
Jul 1, 1995, Hartwell, Frederic P.
Improperly substantiated horsepower designations on pool motors and other appliances may resize many circuit elements without increasing safety.We received...
Zone concept advances. (classification of hazardous locations) Under the present NEC rules, hazardous (classified) locations are divided into divisions depending on how frequent the hazardous atmosphere or dusts are expected to be present. If the hazardo
Jul 1, 1995,
EC&M provides the latest design and engineering news and analysis in the electric construction and maintenance industry....
Using AC coils on DC power
Jul 1, 1995, Hoestenbach, Roger D.
You can use AC coils on DC circuits providing you apply enough DC voltage to draw the same amount of current as when operating on AC.Here's an alternative...
Protecting life safety circuits in high rise buildings.
Jul 1, 1995, Staszewski, Zygmunt
Fire damage to emergency circuits in high rise buildings must be prevented. When combined with smoke and heat spread, such damage may result in far greater...
When service protection can be higher than ampacity
Jul 1, 1995, Stallcup, James G.
Protecting service-entrance conductors when there are motors and other loads.The basic requirement in Sec. 230-90(a) is that the fuse size or circuit...
Protecting high-efficiency motor circuits.
Jun 1, 1995, Hartwell, Frederic P.
Some types of overcurrent protective devices may not prove suitable for all high-efficiency motor applications.We received a series of questions related...
Using demand data to analyze load additions.
May 1, 1995, Stallcup, James G.
Can a new commercial or industrial load be added to existing service equipment without performing an extensive standard calculation?For many years designers...
Receptacle configurations on highly loaded circuits.
Apr 1, 1995, Hartwell, Frederic P.
There are circumstances when a plug and receptacle configuration can be used above the normal limit of 80% of their rating.We received some manufacturer's...
Is unobstructed workspace required at all times?
Mar 1, 1995, Hartwell, Frederic P.
Although switchgear must be readily accessible and meet minimum working clearances, the entire workspace need not be readily accessible.The drawing shows...
Tying new MV feeders into an existing system.
Mar 1, 1995, Canham, James; Zec, Joseph; Pullizzi, Jack E.; Ciasulli, Mario
Power feeders for a new cooling tower require special design and installation considerations to be compatible with the existing power distribution system.Tying...
Determining submersible pump cable sizes.
Mar 1, 1995, Duhan, Jeff
How are voltage drop calculations used in sizing submersible pump power cables?What happens when the power source for a submersible pump is not located...
