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Posts Tagged ‘bus plugs’

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.

Will Not Test Only – From Bus Plug List of 10 Things We Will Not Do

March 28th, 2011 Comments off

 

SB323R General Electric Bus Plugs For Sale by MIDWEST

SB323R General Electric Bus Plugs For Sale by MIDWEST

On MIDWEST’s list of “Ten things we will not do with bus plugs” is “We will not sell a bus plug that we have tested only.” In other words, we are not going to take a Square D bus plug and just test it and say it is okay. We are not going to take a Cutler Hammer bus plug and sell it without reconditioning it.  We are not going to sell a GE General Electric bus plug unless we have reconditioned it and tested it first. We are not going to sell an ITE bus plug after doing only a “smoke test,” as one really old time electrical contractor was fond of asking us. An old timer’s really scary minimum specification. When he turned it on, he just didn’t want to see any smoke. That was all he was concerned with. So he said. Actually we worked with him for decades and he always came back because he knew we did everything, including reconditioning and testing the bus plugs, anyway. We are not going to sell a Siemens bus plug as is, even for temporary use. We are not going to sell a Westinghouse bus plug after reconditioning and testing, if it still does not pass our final quality control inspection. All these statements are a repeat of the basic same “We Will Not Test Only” from the list of ten things we will not do with bus plugs. Sometimes it can be enlightening to say one thing six different ways, if it is making an important point. For quality and safety, pleonasm may be your friend.

 

Finding Bus Plugs in White Space

January 18th, 2011 Comments off
 
Bus Plug Square D PKA36200

Bus Plug Square D PKA36200

If you read the recent information on Facebook beating Myspace by managing in “white space,” rather than in a formal business management environment, you have a good idea how MIDWEST makes many decisions to improve its web site for our customers. We make so called guesses based on conversations and suggestions from our customers.  They tell us what they like. And in doing so, they are the white space between all the seasoned directives we get from the marketing professionals. The ‘world wide web’ is still exciting uncharted territory.  There are not many years of prior art.

In response to customer white space chatter, MIDWEST set up a web site specifically directed at those looking for buyers of bus plugs. Hence, the domain name www.busplugsbuyer.com. You see here the results of white space management. This specific target site makes it easier for those that have bus plugs to sell to find us in general. Of course, they could find MIDWEST specifically if they already knew we existed. But, for those that don’t know who MIDWEST is, they might make a general search for buyers of bus plugs. Then go from the general to the more specific. Specifically, whether a GE General Electric bus plugs, Square D bus plugs, Cutler Hammer bus plugs, ITE Bus Plugs, or Federal Pacific bus plugs, it doesn’t make a difference.  According to our customers, they would first search for a bus plug buyer and then go from there. This is all very simple from the seller’s point of view.

Infrared Scanning Bus Plugs when You Can Not Open the Cover

December 10th, 2010 Comments off
 
General Electric AC323R Bus Plug Available from MIDWEST

General Electric AC323R Bus Plug Available from MIDWEST

Sometimes you just can not safely perform an electrical maintenance service per the written specification. For example, in today’s world of real concern for arc flash hazards, safely opening the cover of an energized bus plug, to perform an Infrared Scan, may not be possible. It may not be safely justified because of the high risk. So one argument is whether or not one can actually tell if a bus plug is hot because of overloading or because of a poor connection that is overheating. Is it a load problem or a connection problem?  Is there a problem at all?

Because our Thermographers are all required to work on bus plugs in our switchgear shop, they are very familiar with the interior of most bus plugs. They may have totally reconditioned a specific Square D or Bull Dog 100 amp bus plug. Or they may have repaired many ITE, GE General Electric or Cutler Hammer 60 amp bus plugs. Therefore they know where the interior switch or breaker is located. They may know exactly where the conductors connect to the bus plug feeder terminals.  This knowledge and experience is a big advantage, but the Infrared task is still difficult. The indications of overheating, whether load or connection related, may be very subtle because the interior heat must be re-emitted by the bus plug enclosure, greatly dampening the heat pattern.

Again, knowledge of the bus plug allows the Thermographer to turn art into science, at least to some degree. The thermographer may compare a suspect old bus plug to an identical bus plug nearby. Comparing the feeder conduit helps identify the possible ampacity of an old bus plug.  Comparing the heat pattern of the different plane surfaces of a suspect old or new Cutler Hammer or Square D bus plug may give additional information to help determine the existence and cause of heating.

 

Our thermographers have special safe ammeters to measure the load on a bus plug feeder, where practical and safe. Knowing the actual load, say on a feeder from an old Federal Pacific bus plug, is extremely helpful in determining if the suspected heating is load related or connection related. It is extremely difficult, if even possible, to determine the presence of overheating, much less the cause, by just looking at one plane of the energized bus plug with even a very sensitive Infrared Scanner.

 

It is the combination of the Thermographer’s experience and equipment knowledge that makes scanning energized bus plugs still very useful.  This same experience and knowledge aid in determining the possible cause of a suspected problem manifested by heat.

Broken Handle Bus Plug

November 10th, 2010 Comments off
 
XLVB322 ITE Bus Plug

XLVB322 ITE Bus Plug

Once in a while MIDWEST gets phone calls that are just scary.  For example, a maintenance electrician called to ask what he should do. He needed to turn power off to a production machine. It was fed directly from an old bus plug. But the bus plug handle was broken so he couldn’t switch the bus plug. He tried using a vice grip, but the whole bus plug was moving and it still would not turn off. Production said they could not turn off the whole line just for one lousy switch. He said the bus plug was obsolete and he just wanted to get it out of there. It was kind of hanging at an angle and the pipe for the feeder going out the top was pulled out. He thought he and another guy could use a lift and pull it off live. He thought that might be okay because they would make sure there was no load on it.  He said he had worked on broken bus plugs before.

This man was in a big jam between making a bad decision and doing what his boss wanted. He needed help. Our answer was simple and we told him we would send a letter if he needed. There was danger of serious injury or death if they tried to remove that live bus plug from a live bus duct. The bus duct would have to be turned off. The danger of shock hazard and arc blast hazard was too great under the circumstances. In addition, the situational danger was extreme because they would be working from a platform lift with no way to escaped from shock or arc blast. Plus they could be knocked right off the platform. And they were in a position that no one could immediately help them.

 

We were sure his boss did not fully understand the level of danger and just saw the problem as simply mechanical. We have been through this before. Once everyone understands how dangerous it is, they work out a safe solution, like turn the power off on third shift.

 

The big danger is beginning to think you can do something that you know is too dangerous. Sometimes, the longer you think about it, the more you convince yourself that maybe this time it would be okay. You’ll just be careful. When you start that line of thought, you just have to stop yourself.

 

If you know there is a danger of serious injury or death, you are not allowed to do it.

Bus Plugs the Most Colorful Electrical Equipment

October 8th, 2010 1 comment

MIDWEST was asked what electrical equipment was the most colorful.  Certainly a strange question, But the answer may seem even stranger.  The most colorful equipment is electrical bus duct and bus plugs. We’ve seen a thousand manufacturing plants over the years and many, especially the older ones, have painted their old electrical bus duct and bus plugs specific colors to identify the specific electrical system or the specific load being fed. Here are a few examples.  One plant painted the 480 volt bus duct and bus plugs blue and painted all their old 240 volt system orange.  It would be hard to mix these systems up. Another plant, a huge facility with over a thousand old Square D and Westinghouse bus plugs, painted everything black. It was pretty impressive, until you tried to read some of the labels on the obsolete bus plugs. Some facilities will paint a particular bus run a specific color to identify it as belonging to a specific manufacturing process. They want to separate the process load from general building load.  Blue seems to be the choice of colors for equipment feeding specific processes or manufacturing cells.  Critical processes may use red.  Some may paint their GE General Electric bus plugs one color and the Cutler Hammer or Westinghouse bus plugs a different color. And then there are those facilities that had a color code many years ago, but have added other manufacturers’ equipment since then.  And now you find different old colored bus plugs on the same bus duct with plain grey new bus plugs.  We have seen some pretty strange stuff. There are some facilities that were former manufacturing plants that had their own electrical engineering staff and maintenance electricians working all three shifts. Everything was well maintained. Things were labeled. Equipment, including old and new bus duct and bus plugs, were maintained and repaired or replaced as needed. They even had up to date electrical drawings. Those were the days.  Now some of those same facilities are multiple occupancy buildings with light assembly, storage, office space and, too frequently, abandoned space. And the colorful electrical distribution systems all seem to have become one color. We’ll call it sad grey. 

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.

Bus Duct Capacity and Connected Load

August 13th, 2010 Comments off

MIDWEST was asked why the total capacity of all the bus plugs connected to a 1600 amp bus duct was over 2500 amps. The particular facility had one 400 amp bus plug, four 200 amp, eight 100 amp, and twelve 30 to 60 amp bus plugs on the old bus duct.  These were mostly very old bus plugs and a few reconditioned or new bus plugs. Purchasing wanted to order two new 60 amp bus plugs but didn’t know how it was possible to have over 2500 amps connected to only a 1600 amp bus duct and then add more. Actually the equipment he wanted was no longer manufactured, so he would have to use old reconditioned or refurbished bus plugs. It was a maintenance man asking purchasing the question.  This was a case were the maintenance man was doing production equipment repair one day and electrical maintenance the next. But he was not an electrician by trade.  MIDWEST explained.  The size of the bus plugs is nominal. The actual fuse or breaker in the bus plug may have a lower rating. For example, a 100 amp bus plug may have a 60 amp fuse. Or 250 amp fuses in a 400 amp bus plug.  In addition, all connected load is not on all at the same time. There is a diversity factor. The diversity of an old or new bus duct system might result in only 50% loading. It would not be unusual for a 2000 amp bus duct to have less than 1200 amps on it. We get extremely nervous if the load approaches 80%. We see a huge increase in problems when this equipment is operating anywhere near full rating.  When we infrared scan a bus duct that is heavily loaded, the whole bus duct and many of the bus plugs just seem to light up under infrared. So usually old and new bus plugs and bus ducts are not loaded to full rating, but when they are, bad things start to happen. If the load is not known, it may be easy to spot measure the load on the bus plug feeders. Do this safely at the load. Do not measure load at the bus plugs. That would be extremely dangerous.  Always, safety first.