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Posts Tagged ‘Square D’

Bus Plugs: We’ve got what you need – All Manufacturer’s

February 23rd, 2015 Comments off

Bus Plugs:  We’ve got what you need.  MIDWEST sells reconditioned, used and new Bus Plugs.   All manufacturer’s available – Square D, ITE, General Electric, Westinghouse, Cutler Hammer, Bull Dog, Continental, Federal Pacific, Gould, Siemens, etc.  Call today 800.803.9256!  http://www.swgr.com/store/Bus-Plug-Home.aspx

Bus Plugs – Where are they used

May 23rd, 2012 Comments off
PFA34100GN Square D 100 Amp Bus Plug For Sale by MIDWEST

PFA34100GN Square D 100 Amp Bus Plug For Sale by MIDWEST

MIDWEST is frequently asked where and how bus duct and bus plugs are used. Often the person asking works at a commercial facility, office, or processing company where the electrical power is distributed using just pipe and wire.  There may be no large open manufacturing areas. Here are a couple examples of facilities that use bus duct and bus plugs to distribute power around the facility. A metal fabricating plant may use Square 800 amp bus duct to distribute power throughout an open manufacturing area where they have machines they move around from time to time.  Part or the whole process may be rearranged depending on the product at the time. A Square D 100 amp bus plug,  PFA34100GN, may feed a 100 amp welding plug or the power and control compartment of a milling machine. There might be 25 or more bus plugs on the bus duct. And they could easily add new bus duct and new bus plugs to accommodate expansion.  Another example might be a very large open area or high bay facility for heavy manufacturing using a 2000 amp Square D bus duct with over a hundred bus plugs on it.  The bus plugs provide building power to power panels and lighting panels and to production equipment and process equipment. Bus duct is a very efficient way to get a lot of power to a large area where the power distribution keeps changing. Unlike office and commercial facilities, manufacturing plants have a need to put a lot of power to different areas that sometimes require additions and changes. Unlike fixed pipe and wire, the power capacity and flexibility of Square D or GE General Electric, Siemens, or Cutler Hammer bus plugs and bus duct is perfect for these environments.

When Bus Plugs Start to Fail Frequently

January 10th, 2011 Comments off
 
Square D PQ3206 Bus Plug

Square D PQ3206 Bus Plug

It is not unusual for MIDWEST to get a call because a company is having numerous problems with their old bus plugs. Things go along okay for years and then one year they have one failure after another. It seems to make no difference who the manufacturer is. They could be old Square D bus plugs, GE General Electric bus plugs, Westinghouse bus plugs, Cutler Hammer bus plugs or ITE bus plugs. The problem seems not to care who the manufacturer is.  When this pattern appears, it is usually because a chronic mechanical or environmental problem has been present for many years and has been getting progressively worse. Soon or later the mechanical problem or contaminate reaches a critical stage and the bus plugs collectively start to fail. Usually the failure seems to be caused by overheating, or by mechanical failure between the bus duct and bus plugs, or by moisture.  The problem isn’t just moisture or dirt. It’s the accumulation of dirt over many years or the presence of moisture over many years. This means there is a chronic condition causing you to replace bus plugs. One typically doesn’t have to suddenly replace Square D bus plugs or replace Cutler Hammer bus plugs because of normal operating conditions. And replacing Westinghouse bus plugs one after the other without addressing the root cause, will not make the problem go away.  So if you find yourself having to repair or replace numerous bus plugs, look for a chronic cause. If you just don’t find something, then look for a recent acute change that would affect all the bus plugs.

 

 

 

 

Bus Plug Connection or Load Problem Using Infrared

November 24th, 2010 Comments off

MIDWEST frequently is asked how we can tell if an overheating problem in an electrical bus plug, found using Infrared Thermography, is a connection problem or a load problem. Especially when the bus plug cover can not safely be opened.  Overheating from a load problem usually displays a paintbrush effect on the bus plug enclosure. Large and continuous areas may display a higher temperature pattern. Looking at the electrical bus plug from different angles may still display a wide pattern of overheating and no indication of a spot source. This is difficult, even for an experienced Thermographer. MIDWEST’s Thermographers have the advantage of extensive training and experience reconditioning, maintaining, repairing and testing bus plugs in our switchgear shop. With this experience, they know the location of the internal components of the various bus plugs, whether Square D, Cutler Hammer, GE General Electric, Westinghouse, ITE Bulldog, or Federal Pacific. The combination of this knowledge and experience and their understanding of Infrared Thermography, gives them the tools they need to best differentiate between overheating due to load and overheating due to a poor connection or contact.

 

A connection problem may display a more localized heat pattern that sometimes can be confirmed by Infrared Scanning the bus plug from different angles.  The heat pattern at each angle may confirm the heat is coming from the same somewhat specific location.  With the cover closed, it is very difficult to identify the exact location. It might be the fuse clip or the lug for a feeder cable or the switch or breaker contact.

 

Finally, when possible, measuring the load on the bus plug feeder, when safe, and comparing it to the bus plug rating can help validate whether the problem is load or connection. Only when safe, the bus plug cover may be opened and an accurate scan of the inside of the bus plug performed.  It is not always possible to determine the exact cause of overheating in a bus plug, but these are some of the tools that increase our success.

Bus Plug Clearance Safety

September 24th, 2010 Comments off
 
Square D Bus Plugs Cat. No. PQ4620

Square D Bus Plugs Cat. No. PQ4620

We ran across blogging information about safe clearances for bus plugs. There was interest in the correct code requirements for various size bus plugs, 2000 amp bus plugs to 400 amp bus plugs to 60 amp bus plugs. Sometimes code requirements are the only hammer the electrician may have to force others to be safe. We’ve dealt with used, obsolete, and new bus plugs for decades and we have one big rule for experienced electrical personal who work around this stuff for a living. “If it seems unsafe, it is unsafe.”  As far as inexperienced or non electrical folks, stay away from electrical power bus plugs. They are not your friend.

 Would it make sense to tell an experienced electrician, who feels that a 200 amp Square D bus plug is unsafe to fool with, that he actually would be safe just because it meets code. Nonsense. We would trust the extra caution of experience, over code, any day, especially when the code is defined as a minimum safety standard.  Having said this, we would also caution against listening to the type of experience that says something is safe, even though it does not meet code, just because the experienced person has done it many time before and nothing ever happed.  Experience or not, just don’t work on or around anybody’s bus plugs hot. Whether Square D, Cutler Hammer, GE General Electric, or Siemens bus plugs, do not work on bus plugs energized.

 

Sometimes the criticism of the location of electrical bus duct and bus plugs is heaped on the electrical contractor that installed it. Having worked in electrical contracting in a past life and worked in manufacturing plants for decades, we often find the electrical bus duct and bus plugs are ignored when other equipment is installed near them.  Space is a premium, so newly installed pipe or duct or hangers can go only a foot or two from the bus duct or plug.  And after 20 years, there isn’t enough room left for an electrician to safely work around bus duct or plugs, regardless of code or experience.  So don’t! 

Having Bus Plugs from Many Manufacturers

September 15th, 2010 Comments off

MIDWEST was asked by a manufacturing plant that used Siemens bus plugs in their facility, why they had not only Siemens bus plugs, but also used ITE Siemens, Square D and Cutler Hammer bus plugs. And most of his main switchgear and circuit breakers were GE General Electric. His purchasing department wanted maintenance to pick one electrical equipment manufacturer and stick with them. Purchasing figured they could get better prices that way. 

 

ITE Bus Plugs Cat. No. RV424

ITE Bus Plugs Cat. No. RV424

First we explained that each type of electrical equipment they had, probably represented a time period or an expansion project. For example, that 100,000 square foot addition in 1968 may have been all Square D. The electrical contractor may have got his best pricing from Square D and therefore bought Square D bus plugs and bus duct. The contractor on a later project may have used Cutler Hammer. Later yet, Siemens. This was not unusual. Or this may have happened because of different delivery dates. Or a particular manufacturer of bus plugs may have fallen out of favor with contractors because of quality problems or high prices. 

 

All this could be avoided by specifying a specific manufacturer. But single sourcing one manufacturer of electrical switchgear may result in higher prices. The manufacturer would have a lock on the sales. The manufacturer’s sales rep would usually figure this out pretty quick. If you put an alternate in your specification, you basically have the same environment as open source bidding.  Sometimes a particular electrical bus duct and bus plug manufacturer has a lock on a customer’s business because of the purchasing department or maintenance department at that time. The head of maintenance for ten years just may be more familiar with or favor GE General Electric bus plugs. Or purchasing may be hooked on Eaton Cutler Hammer bus plugs. So it goes sometimes. But it can be very difficult to continually single source the electrical equipment you purchase for many years and decades. There are just too many variables and they change over time.  There is not a problem having equipment from different electrical equipment manufacturers, as long as replacement bus plugs or other equipment and parts are readily available. Delivery is sometimes a problem in today’s ‘just in time’ world. MIDWEST’s reconditioned electrical switchgear, including bus plugs, is one solution to the availability problem. 

 

There are situations where using only one manufacturer of electrical switchgear may be important and required. For example, Mission Critical facilities, remote access facilities that require many spare components, continuous process facilities, and, of course, facilities that are actually subsidiaries or are owned by a specific electrical equipment manufacturer.