AVR 3550 (serv.man13) - Harman Kardon Audio EMC - CB Certificate (repair manual). Page 43

 

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IEC 60065, 6th edition : 1998

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- Page 39 of 40 - 

 

 

   

 

Order No. 

200219130

 

 

 

 

 

FAULT CONDITION TESTS (continued)   

Comp. 
No 

Fault 

Test V 

Position 

Test time  Fuse No 

Current 
through 
fuse 

Mains power/temperatures/results 

D901 

S-c 

254,4 

A - C 

14 min 

F902 

0,03 A 

Pr. relay RY94 off immediately. 
Input current stabilised at 0,03A. 
Sub-transformer pr. winding heated 
up to 121K and thermal fuse opened 
after 14 min. 
Dielectric strength test OK. 
No hazard. 

C906 

S-c 

254,4 

- 

13 min 

F902 

0,03 A 

Pr. relay RY94 off immediately. 
Input current stabilised at 0,03A. 
Sub-transformer pr. winding heated 
up to 123K and thermal fuse opened 
after 13 min. 
Dielectric strength test OK. 
No hazard. 

IC94 

S-c 

254,4 

Pin 1 - 2 

2 hr 

F902 

1,64 A 

Normal operating. 
No component damaged. 
No hazard. 

C907 

S-c 

254,4 

- 

1 hr 

F902 

0,02 A 

Pr. relay RY94 off immediately. 
Input current stabilised at 0,02A. 
No component damaged. 
No hazard. 

C911 

S-c 

254,4 

- 

12 min 

F902 

0,03 A 

Pr. relay RY94 off immediately. 
Input current stabilised at 0,03A. 
D902 damaged. 
Sub-transformer pr. winding heated 
up to 125K and thermal fuse opened 
after 12 min. 
Dielectric strength test OK. 
No hazard. 

Top 
cover 
opening 

Blocked 

254,4 

- 

10 min. 

F902 
F903 
F904 

1,62 A 

Components are heated up to; 
- Main transf. winding 

: 55K   

- Main transf. core 

: 50K 

- Sub transf. pr. winding  : 42K 
- Sub transf. core 

: 36K 

- PWB near D909 

: 68K 

- C917 body 

: 26K 

- TR, Q657 body 

: 50K 

and protection circuit operated (pr. 
relay, RY94 off) after 10 min. 
Dielectric strength test OK. 
No hazard. 

F No = Fault Number, S-c = Short-circuit, Dis = Disconnection