E55260.htm     Smyrna

HEAT LOSSES FOR METAL-CLAD SWITCHGEAR SERIES 5

1.  PURPOSE

To document heat losses for Series 5 MASTERCLAD Metal-Clad Switchgear. 5-15kV, 50/63 kA

2.  APPLICABLE TO

Design Center, Order Engineering, Marketing and Sales.

3.  PROCEDURE 

-  The on-line .htm document is controlled.  All paper copies of the .htm document are uncontrolled.

CATEGORY INDEX [To Issued Index] [To Master Index]

3.1.  Heat Loss/Heat Rise Tests  To Category Index

The heat losses listed below were measured during the switchgear heat rise tests.  These maximum losses would apply if each breaker and breaker bussing and the main busses were loaded 100% of the time.  If the actual load is not known, the listed 80% load would be a conservative value to use.

DESCRIPTION

100% LOAD

80% LOAD

1200A Breaker

990 Watts

790 Watts

2000A Breaker

1600 Watts

1280 Watts

3000A Breaker

2300 Watts

1840 Watts

1200A Main Bus per Bay

180 Watts

140 Watts

2000A Main Bus per Bay

460 Watts

370 Watts

3000A Main Bus per Bay

720 Watts

570 Watts

3.2.  Heat Loss/CT Rating  To Category Index

 

A more accurate heat loss can be obtained by using 80% of the CT rating of each breaker as the maximum load.  A safety factor should be added if the load may be increased in the future.  The losses listed below are pro-rated from the maximum breaker heat losses. 

CT RATIO

100% LOAD

80% LOAD

  400/5A

330 Watts

260 Watts

  600/5A

500 Watts

400 Watts

  800/5A

660 Watts

520 Watts

1000/5A

830 Watts

660 Watts

1200/5A

990 Watts

790 Watts

1500/5A

1200 Watts

960 Watts

2000/5A

1600 Watts

1280 Watts

2500/5A

1900 Watts

1520 Watts

3000/5A

2300 Watts

1840 Watts

The “main bus per bay” losses have to be added to these breaker losses.

3.3.  Space Heater Adjustment  To Category Index

If units are equipped with space heaters, add 400 watts per bay.

4.  REVISION HISTORY To Category Index

REV

DATE

PREP. BY

APP. BY

CHANGE DESCRIPTION

*

12/96

JWM

JWM

First Issued

A

6/97

TIS

JWM

Converted Text to Word

B

10/97

TIS

JWM

Issue of New Book Format

C

2/12

SFV

SFV

Add 63 kA