LED Blinks Three Times (Convergence Protection)
he transistor Q7060 monitors current of the 20Vdc source. Excessive current
ent
he voltage drop across R7066 to increase. When the voltage drop
becomes sufficient, the transistor Q7061 turns on. This causes Q7060 to turn on.
When Q7060 is triggered on either by Q7061 or by the voltage drop across
R7060, it applies a DC voltage to the voltage divider network of R7063 and
R7064.
The DC level at the node of R7063 and R7064 causes D7060 to conduct. This
voltage enters the DG-Board via pin 11 of the connector D2/A2, and pin 51 of the
connector A31 causing the MPU to activate shutdown and turn off the AC Relay
RL801.
Convergence Amps
IC7101/IC7002
SOS
Norm
DG -BOARD
A-Board
A31
51
A2 D2
11
SOS3
11
D-Board
Figure 45
T
causes the voltage drop across R7060 to increase. When the voltage drop
becomes sufficient, the transistor turns on and applies DC to the voltage divider
consisting of R7063 and R7064.
The transistor Q7061 monitors current of the -20Vdc source. Excessive curr
causes t
83
Summary of Contents for PT-53TWD63
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