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After completing a course or workshop in professional or technical writing from the Professional Communications Group, your employees will be able to revise a “writer-centered,” first draft document like the original below, to create a “reader-centered,” concise, and easily navigable document illustrated in the revision.

Original Document 

This memo is to identify a potential failure of high voltage electrical switchgear in use at the west side facility.  Recently the incoming 13.8KV power at the west side facility was interrupted when voltage flashover occurred in an RTE-Delta Corp. switchgear bus compartment.  The air circuit breaker is rated for 15 KV and 600 amps and is supplied with current limiting fuses.  The breaker and busway are located in separate compartments of one metallic enclosure.  Bus bars are used to connect the breaker load terminals to the busway compartment from which jacketed, 15 KV cable connects to the bushings of a 13,880/480 V transformer.  The bus bars have insulated sleeves and pass through an insulating barrier between compartments.  There is a space heater in the breaker compartment and filtered, ventilation openings in the access door.  The busway compartment has neither a heater or ventilation.  Circumstances indicate that condensation has been occurring in the busway compartment over a period of time.  aided by the presence of moisture, "tracking" (current leakage) occurred between the insulating barrier and standoff insulators.  Ultimately arcing was sever enough to develop fault currents sufficient to open the fuses, resulting in a power failure.  Equipment damage was severe but limited to bus bars and insulators.  An investigation revealed no signs of condensation in the breaker compartment.  Preliminary recommendations include: 1) Remove insulating barrier.  2)  Add space heater in busway compartment.  3) Replace bus bars with continuous cable from breaker terminals to transformer bushings.  It is anticipated that items 1 and 2 will prevent the formation of condensation by allowing the busway compartment to "breathe" and maintain constant internal temperature.  Item 3 will minimize the potential for failure if condensation occurs in the future.  Switchgear similar to this unit, regardless of manufacturer, should be examined and the potential for related failures should be analyzed.

Revision 

Memo

To:     Harold Brown, Section Head 
From: Sam Jones, Electrical Inspector
Date:  18 Dec. 2001 
RE:     Prevention of power outages

Last Thursday's power outage (15 Dec. 01) was caused by moisture buildup in the insulating barrier between two compartments of a 15 KV swtichgear box.  Following these recommendations will greatly lessen the chances of moisture buildup:

1. Remove the insulating barrier where the moisture buildup occurred.

2. Add a heater to the busway compartment, so the the air inside will stay dry.  

Condensation accumulated inside the busway compartment for weeks or months. This suggests that our environment is humid enough to cause moisture buildup, in spite of our efforts to prevent it. Consequently, these additional recommendations will lessen the chances of power failure, even if moisture should build up again:

1. Replace the bus bars in all existing switchgear with continuous cable.

2. Regularly examine all new switchgear and make appropriate modifications before installation.
    

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