Chapter 2 Electromagnetic compatibility

Question 1

TWO DEVICES ARE USING OVERLAPPING OPPERATIONAL FEQUENCIES WITHIN THE SAME EM ENVIRONMENT. WHAT IS THE LIKELY AFFECT ON THE POTENTIAL FOR EMI IN THIS ENVIRONMENT?

Answer 1

THE POTENIAL FOR EMI IS LIKELY TO INCREASE UNDER THESE CONDITIONS.

Question 2

NAME FOUR MECHANISMS THAT CAN CREATE COUPLING BWTWEEN TWO CICUITS OR SYSTEMS?

Answer 2

1. CONDUCTIVE COUPLING
2. INDUCTIVE COUPLING
3. CAPACITIVE COUPLING
4. ELECTROMAGNETIC COUPLING.

Question 3

WHST TYPE OF COUPLING MAY OCCUR WHEN A COMMON AC BRANCH CIRCUIT IS SHARED BETWEEN TWO DEVICES?

Answer 3

CONDUCTIVE COUPLING

Question 4

WHAT CAUSE INDUCTIVE COUPLING?

Answer 4

MAGNETIC FIELDS

Question 5

WHT CAUSES CAPACITIVE COUPLING?

Answer 5

ELECTRIC FIELDS

Question 6

NAME THREE ESSENTIAL ELEMENTS IN PROCESS DURING EMC PROBLEMS?

Answer 6

1. THE SOURCE OF AN ELECTROMAGNETIC INTERFERENCE.
2. A VICTIM THAT CONNOT PERORM AS DESIGNED OR CONFIGURED DUE TO THIS ELECTROMAGNETIC INTERFERENCE.
3. A PATH THAT PROMOTES THE INTERFERENCE BETWEEN THEM THAT ALLOWS THE OSUCE OF THE INTERFERENCE WITH THE VICTIM.

Question 7

WHAT IS THE SPEED OF LIGHT?

Answer 7

300,000 KM/S (186,300 MI/S IN A VACUUM.

Question 8

NAME THE TWO CHARACTERISTICS THAT ARE USED TO DISTINGUISH ELECTROMAGNETIC WAVES?

Answer 8

1. WAVELENGTH (EXPRESSED IN METERS)
2. FREQUECY (EXPRESSED IN HERTZ)

Question 9

TRUE OR FALSE - VISBALE LIGHT REPRESENTS THE LARGEST PORTION OF THE ELECTROMAGNETIC SPECTRUM.

Answer 9

FALSE - VISABLE LIGHT REPRESENTS ONLY A SMALL PORTION OF THE ELECTROMAGNETIC SPECTRUM.

Question 10

NAME THE PRIMARY PATHS THOUGH WHICH CONDUCTED COUPLING MY AFFECT ELECTRONIC DEVICES?

Answer 10

1. INPUT/OUTPUT SIGNAL LINES.
2. UNTILITY OR PREMISE ELECTRICAL POWER DISTRIBUTION.

Question 11

NAME THE FOUR PRIMARY CONDITIONS THAT ALLOW RADIATED INTERFERENCE TO ENTER ELECTRONIC DEVICES.

Answer 11

1. PROXIMITY TO INTERFERING SOURCES.
2. MISSING OR INADEQUATE GASKETS/ENLCOSURES.
3. MISSING OR INADEQUATE BONDING OR GROUNDING (EARTHING) SYSTEM COMPONENTS.
4. MISSING OR INADEQUATE DEVICE OR CABLE SHIELDING.

Question 12

TRUE OR FALSE - ELECTRICAL CODES DO NOT GENERALLY PROVIDE FOR EMC.

Answer 12

TRUE - ELECTRICAL CODES DO NOT GENERALLY PROVIDE FOR EMC.

Question 13

WHAT IS AN ELECTROMAGNETIC FIELD?

Answer 13

A PHENOMENON THAT INVOLVES THE COMBINATION OF ELECTRIC AND MAGNETIC FIELDS TOGETHER, WHICH VARY IN TIME.

Question 14

WHAT TYPE OF CHARGE CREATES AND ELECTICE FIELD?

Answer 14

STATIONARY

Question 15

WHAT TYPE OF CHARGE CREATES A MAGNETIC FILED?

Answer 15

MOVING (ELECTRICAL CURRENTS)

Question 16

NORMALLY, IT IS NOT PRACTICAL TO CONTROL EXTENAL SOUCES OF EMI. WHAT METHODS SHOULD THE ICT DESIGNER USE TO ADDRESS THIS TYPE OF EMI INSTEAD?

Answer 16

ADOPT METHODS THAT ENSURE SYSTEM IMUNNITY AND/OR NOISE REJECTION.