Chapter 11 Troubleshooting

Output circuit troubles and corrective actions (continued).

Condition

Cause

Corrective actions

The load off

y Over current at off state [The large solenoid current

y Insert a small L/R magnetic contact and drive the load

response time

fluidic load (L/R is large) such as is directly driven with

using the same contact.

is long.

the transistor output.

 

Output

Output

Off current

 

Load

 

E

Load

yThe off response time can be delayed by one or more second as some loads make the current flow across the diode at the off time of the transistor output.

Output

Surge current of the white lamp

 

y To suppress the surge current make the dark current

transistor

is

 

of 1/3 to 1/5 rated current flow.

destroyed.

 

Output

 

 

Output

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

E1

R

E

A surge current of 10 times or more when turned on.

Sink type transistor output

Output

R

E

Source type transistor output

11-11

Page 289 Page 291
Page 290
Image 290
LG Electronics 120S Transistor 1/3 to 1/5 rated current flow Destroyed, Surge current of 10 times or more when turned on
Page 289 Page 291
Top Page Image Contents