Dell 5110cn Service Manual page 590

Signal line name
24V OSC OFF
HEAT1
xHEAT1
HEAT2
xHEAT2
HEAT EN
IL OPEN
SLEEP
xREAR FAN STOP
xREAR FAN LOW
ALM FAN REAR
xLVPS FAN STOP
LV TYPE
ALM FAN LVPS
♦
LVPS overcurrent protection circuit
This circuit stops all outputs, if the power supply voltage 24VDC, 5VDC, or 3.3VDC is shorted.
The circuit is reset, when after the cause of short was removed, the power is turned off, and then
on again after certain time.
* Note that the 5 V power supplies for the ESS and operation panel are excluded. The 5 VDC
power supplies cannot be restored since they use a fuse.
♦
LVPS overvoltage protection circuit
This circuit stops all outputs, if the power supply voltage 24VDC, 5VDC, or 3.3VDC exceeds the
specified voltage respectively.
At this time, the operating point is 32VDC or less for 24VDC, 7VDC or less for 5VDC, or 4.4V or
less for 3.3VDC.
The circuit is reset, when the power is turned off, and then on again after certain time.
♦
REAR FAN output circuit
For the xFAN REAR ON (H) signal, the output voltage varies depending on the status of FAN
LOW signal and FAN STOP signal.
FAN LOW
High
Low
High
Low
LVPS FAN is controlled by FAN STOP signal only.
♦
Output stop by I/L Switch
Output is stopped by I/L Switch. +24VDC output from LVPS is stopped by turning off the I/L
Switch connected to LVPS.
Chapter 7 Wiring Diagrams and Signal Information
Control signal for +24 VDC output (High: Output is stopped)
Control signal of Main Lamp placed in FUSER ASSY (LAMP
lights up at "High: HEAT1" and "Low:xHEAT1")
Control signal of Sub Lamp placed in FUSER ASSY (LAMP
lights up at "High: HEAT1" and "LowxHEAT1")
Control signal for AC power supply for Main Lamp and Sub
Lamp placed in FUSER ASSY (High: AC power supply is output)
Signal for opening/closing INTERLOCK SWITCH (High: Switch
opens)
Control signal for Sleep Mode (High: Output is stopped at +24
VDC, +5 VDC and +3VDC)
Control signal for REAR FAN (High: Fan rotates)
Control signal for REAR FAN (High: Fan rotates at high speed/
Low: Fan rotates at low speed)
Alarm signal for REAR FAN (High: Fan fails)
Control signal for LVPS FAN (High: Fan rotates)
Identifying signal for LVPS
Alarm signal for LVPS FAN (High: Fan fails)
FAN STOP
High
High
Low
Low
7 – 9
Description
FAN REAR ON(H)
24V
15V
0V
0V