Specification Of The Fan Control; Operation Specifications - Pioneer PDP-5020FD Service Manual

5

[2] SPECIFICATION OF THE FAN CONTROL

Block diagram
The external fans cool down the whole unit.
DIGITAL Assy
Module_Ucom
If an emergency signal
is detected, it will be
transmitted.
Main_Ucom
The Main micro-
computer controls
the IF microcomputer
as a port expander.
IF_Ucom
MAIN Assy

Operation specifications

DAC output
External FAN
DAC2
DAC1
STOP
0xFF
Notes:
• The operating temperature of the fan is higher than the ambient temperature, because the sensor temperature is read by
the microcomputer.
• If the critical values for signals are displayed in the address circuit, the fan may be activated or be rotated at higher speed
in response to values lower than the set temperature values shown above.
• When the temperature rises, the sensor voltage of TEMP2 decreases.
• When the voltage of the DAC output for external FAN decreases, rotation speed of FAN rises.
5
6
IO Assy
TEMP2
TEMP2
FAN_NG2
FAN_ON2
FAN_CONT2
39.0 ºC 41.0 ºC
PDP-5020FD
6
7
External fans
FAN
CONNECT
OR
Assy
R
Detection of
disconnection
FAN_VCC2
FAN_2_
0 to 12V
REG
VOLTAGE
CONTROL
Temperature SD
47.0 ºC 50.0 ºC 62.0 ºC
7
8
A
B
C
D
E
F
83
8