Safety Check after Servicing

Examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires have been returned to original positions. Afterwards, perform the following tests and confirm the specified values in order to verify compliance with safety standards.

1. Clearance Distance

When replacing primary circuit components, confirm specified clearance distance (d) and (d') between soldered terminals, and between terminals and surrounding metallic parts. (See Fig. 1)

Table 1: Ratings for selected area

AC Line Voltage

Region

Clearance

Distance (d), (d’)

 

 

 

 

 

 

 

 

110 to 130 V

U.S.A. or

3.2 mm

Canada

(0.126 inches)

 

 

 

 

Note: This table is unofficial and for reference only. Be sure to confirm the precise values.

Chassis or Secondary Conductor

 

Primary Circuit

d'

d

Fig. 1

2. Leakage Current Test

Confirm the specified (or lower) leakage current between B (earth ground, power cord plug prongs) and externally exposed accessible parts (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.).

Measuring Method: (Power ON)

Insert load Z between B (earth ground, power cord plug prongs) and exposed accessible parts. Use an AC voltmeter to measure across both terminals of load Z. See Fig. 2 and following table.

Table 2: Leakage current ratings for selected areas

Exposed Accessible Part

Z

AC Voltmeter

(High Impedance)

BEarth Ground

Power Cord Plug Prongs

Fig. 2

AC Line Voltage

Region

Load Z

Leakage Current (i)

Earth Ground (B) to:

 

 

 

 

 

 

 

 

 

 

110 to 130 V

U.S.A. or

0.15 F CAP. & 1.5 k

i 0.5 mA rms

Exposed accessible

Canada

RES. Connected in parallel

parts

 

 

 

 

 

 

 

Note: This table is unofficial and for reference only. Be sure to confirm the precise values.

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Magnavox MWC24T5 Safety Check after Servicing, Clearance Distance, Leakage Current Test, Measuring Method Power on