ELECTRONIC RELAY TESTER 



937 



correlation is obtained between the static and dynamic gauge measure- 

 ments if make contacts are gauged on operate and break contacts on 

 release. 



OTHER RELAY CHARACTERISTICS 



Switches are provided to permit other relay charcateristics to be ob- 

 served on the scope such as armature motion, contact chatter, and the 

 contact operate and release times. The contact gauging is obtained with 

 the horizontal plates connected to the electrostatic gauge. With this 

 setting, the time for a dot to move across the screen may be less than 

 3 milliseconds (depending on the armature transit time) and contact 

 chatter may be observed during this time. 



With a time base sweep on the horizontal plates, the armature motion 



-H6 5V 



119E oJ 



REPEATER «=5 



COIL -^ 



l<y" 04 10- n. 



2? °3 R3 2° 3^ 



' * * » \AA; t * \ 



FROM DC 

 AMPLIFIER 



positions: 



1. OFF 



2. OPERATE 



3. RELEASE 



4. OPERATE 8. 

 RELEASE 



R4 



f\J\f\ +165 V 



Fig. 8 — Schematic of oscilloscope brightening circuit. 



