Bus Plugs Blog – Expert Safety and Usage Information

Square D PBQ3660 Bus Plugs For Sale by MIDWEST

MIDWEST’s Switchgear Shop had an urgent request for twelve bus plugs, including a large Square D PBQ3640 and Square D PBQ3660, 400 amp and 600 amp bus plugs. It’s not unusual to get urgent requests for bus plugs, but it was a little news worthy to get an emergency request for twelve bus plugs, including a 400 amp and a 600 amp bus plug. As it turned out, the bus plugs were for a former manufacturing plant that had been sold. The new owners were trying to get heat into the building before the Northern winter froze all the water pipes and who knows what else.  But they ran into a big problem.  Copper thieves had stolen a bunch of the electrical equipment, including large bus plugs. They left the really small bus plugs. The owners thought they got lucky because the thievery looked like a project in progress just when the owners began their restoration work. It looked like the thieves had just started taking the electrical stuff closest to the rear loading dock doors. In the process of removing the bus plugs, they damaged the bus duct. It looked like they just unbolted the plugs and let them fall. A lot of work for not much copper.  Thieves sometimes will just cut down the whole bus duct with the plugs attached.  But that’s dangerous and very loud. It is so unfortunate that the theft of a small amount of copper can be so expensive to repair and replace.

Replacement Square D 100 Amp Bus Plugs, Catalog No. PQ4610 – Available at www.swgr.com

MIDWEST had a customer who used MIDWEST’s field services for over 20 years and did not realize there was a secondary market for electrical bus plugs and other electrical switchgear that no longer is manufactured. He was speaking to a MIDWEST Field Service Engineering Technician and was complaining that he might have to replace a 1600 amp bus duct run because the bus plugs were obsolete. He was not an electrician or the electrical supervisor. His job was in purchasing. The electricians asked him to get a replacement Square D 100 amp bus plug because the handle broke on one of theirs.  It is strange how many handles get broken on electrical equipment. It is understandable on some of the older stuff that has been in service for 40 plus years. Gets old, tired, and finally breaks.  Our Electrical Technician told him MIDWEST deals in the secondary market for obsolete electrical equipment and we would have completely reconditioned bus plugs to replace his obsolete defective stuff. He was extremely happy and looked forward to telling his boss he could save 1000s of dollars. On top of it all, they also ordered GE General Electric FVK425R bus plugs to boot. MIDWEST’s Switchgear Division said they run into this a lot. Frequently they get emergency calls to repair an obsolete piece of equipment as fast as possible and end up just replacing the defective equipment with a reconditioned direct replacement. The secondary switchgear market at its best.

Buy Square D PQ3640 Bus Plugs

All too often our little friend the bus plug ends up making the ultimate sacrifice resulting in a catastrophic failure in the line of duty.

Not long ago we got a call from a customer asking for a bus plug replacement for one of theirs which failed in service. The circumstances surrounding the bus plug failure cannot be discerned.

The bus plug involved was a Square D PQ3640 (3 phase, fusible, 600 volts, 400 amps), the older version of the Square D PBQ style bus plug. One can only speculate as to what happened exactly, but the evidence told of a frightening scenario. A hole the size of an orange was burned completely through the bus plug cover. The inside guts burned beyond recognition, copper splattering along with carbon residue scattered throughout the inside of the bus plug.

Oddly enough the extent of the damage was confined to the bus plug itself and did not affect the bus duct proper. As mentioned many times before, bus plugs often operate under highly stressed conditions seriously compromising their life in service.

Three answers, NO and NO and NO.  This is a big deal for us. MIDWEST does not sell old, used, or obsolete bus plugs, circuit breakers, transformers or other electrical equipment to an end user, ie the consumer, unless it has been properly serviced, reconditioned, tested, and passed Quality Controls.  We strongly recommend no one buys old electrical equipment “as is.”  That could be very dangerous. There are many “listing” companies and auction type sites that sell “as is.”  For example, eBay does not warranty the used and old electrical equipment sold through their service.  They provide a great service, but they do not provide a warranty on the specific used electrical equipment sold on eBay.  The same may be true with services that just list equipment.  The only people MIDWEST will sell electrical equipment “as it,” are other qualified electrical dealers that have proper Quality Controls.  Old, used, or obsolete circuit breakers, bus plugs, transformers, and switchgear have too many dangerous failure modes to be sold without proper testing.  MIDWEST does not just process orders.  Anybody can do that.  And many do.  We actually have a name for that.  We call it TC, Trained Chimpanzee, work.  You could train a chimpanzee to put old circuit breakers into a box. 

We add value.  Our staff of engineers and technicians service, repair, recondition, and test electrical equipment for a living.  We’ve done it for over 30 years.  That is what we do day after day. And it is what we think others should do if they are going to sell something.  “As Is” is just scary.  When electrical equipment gets unhappy, it can fail with a boom and a flash.  And that can hurt.

By Walter Powell, Professional Engineer, MIDWEST

Here we go again.  The question asked was “Why would I ever buy a used bus plug?”  It isn’t the question that caused a loud groan, it’s the distain with which the question was asked, by someone who had no idea what a new or used bus plug was.  In their defense, they were just ‘processing’ an order to “Get one of these!”  Actually, these days it is unusual to deal directly with an official purchasing agent or buyer. Usually we deal with electricians, engineers who actually work for a living (Sorry for the bias), and frequently a real live official maintenance supervisor who calls at 5:15 PM to order that bus plug that he has to have the next day.  He’s calling after 5 because that is the first time all day that he has had a chance to take a breath without being interrupted.  These are the people that really keep the wheels moving in a manufacturing plant.

“Why buy used instead of new?” The short answer is:  You wouldn’t buy a used bus plug unless you had to.  Why in the world would you buy used if you don’t need to?  Obviously there are exceptions, such as classic cars, books, wine, art… you get the idea.  But in the world of industry, decisions affecting the day-to-day operation just aren’t that simple.  Decisions have to be practical and frequently are based on the needs right now.  Not tomorrow or next week.  Get it done and move on.   So here is the litany to answer the question.

The “Positives” of buying a New Bus Plug:     Made with all new material; Full reliable life expectancy; Should be trouble free; Manufacturer’s new equipment warranty; No worn or deteriorated parts; Should operate per new product specifications; May have design improvements making it more reliable or safer; and It sure looks good.      

The “Negatives of buying a New Bus Plug:     Delivery time; May require a conversion kit to fit in place of the old or obsolete product; and Cost.

The “Positives” of buying a Used Bus Plug:     Immediate availability; Replacement for something obsolete, just no longer available new; Minimum down time with an exact replacement; and Cost.

The “Negatives” of buying a Used Bus Plug:     Deteriorated parts; Poor quality control of supplier; No mfg’s original warranty; shorter reliable life expectancy; and poor appearance.

So what does one recommend?  Try this!  If you can, buy new.  But if you can only get a used bus plug quick enough to take care of your problem? If you just can’t wait for a new bus plug, then MIDWEST, suggests you get a used bus plug from a company that properly reconditions the bus plugs and also performs standard quality control tests and performs special “performance tests” at full current and voltage. This is extremely important.  A used bus plug just purchased “as is” from a reseller or equipment list may be “as is, buyer beware.”  Ask exactly what the supplier does to the used bus plugs they sell.  

You might ask what makes us such an “Expert.”  Its experience, training, education, experience, and finally more experience.  You wouldn’t ask a police officer a tax question.  You would go to an accountant, someone you perceive to be an expert in his or her field.  And you wouldn’t ask an account to protect you from a thug. You would ask the expert at protecting people from thugs.  And you would base you perception of “who is an expert” on their training and experience, and their willingness to help.  So, when making a decision about new and used electrical bus plugs, you would want to go to an “expert.”  Go to the manufacturer for new bus plugs and go to the experts, such as MIDWEST, www.swgr.com, for reconditioned bus plugs.  One of the nice things about real experts, especially in our electrical world, they are always happy to help by just answering your questions.

Or sorry not me, I have something planned later tonight

By Dan Marchewka

Huh?

Dangerous Waters,  Aguas Peligrosas

A famous actor once said, (I forgot his name) “Do you feel lucky today, Well do you, punk?”

Those allusions may be a little extreme, but are they really?

Older electricians (there are still some around) remember the days of open Frankenstein switches (there are still some in service today), those fabled switches of yore, who take their namesake from Frankenstein movies as electrodes strode across open air circuits and voltage danced freely around the laboratory like gypsies at a wine tasting festival. The Frankenstein switch, open knife blade switches typically mounted on slate boards, were thrown in live by hand. In those days PPE (Personal Protective Equipment) were not yet a distinct part of worker safety. In fact, back then, worker safety was not yet considered part of worker safety.

Where is all this leading? Hang on. Meet the door operated bus plug, a second cousin to the floor operated bus plug. While these two little devices are of the same family and serve the same purpose, the former is the troubled nephew of the clan and is not (skeptics are you listening) for the faint of heart. Older door operated bus plugs such as the Square D Safeflex, for example, (there are others from other manufactures)  were designed such that the door, as in metal door, as in bare metal door handle, were part of the bus plug’s operating mechanism. Now here’s where it gets good. The person opening the bus plug door, say to change out a fuse, balancing himself, (not herself, there weren’t as many women electricians around back then)  up high on the Scizzors lift, believing the load is off, (he knows the end machine has been turned off) was most often not fully appreciative of the surprise he was about to engender. Opening the door, unless he was made of stone, would reveal a startling revelation: A gee-wiz moment, (people don’t say gee-wiz anymore do they?) Ok a holy *hit moment. As anyone who’s done it can testify, opening the door of a door operated bus plug is like prom night but without the tuxedo –you never know what awaits you. The movable contacts of the bus plug switch are part of the bus plug door. While load may be off the circuit the voltage is not. Opening the door breaks the circuit.  So let the word go out to friend and foe alike, the torch has been passed to a new generation of Americans. When conducting this high wire circuit interrupting act be careful to identify the type of bus plug and always wear your appropriate protective equipment.

For you older electricians I know what you are thinking, it was the fun part of the job. Fair enough.

Be safe….and remember, bus plugs are “Dangerfields”…they deserve your respect.