Sony SNC-WR632C Service Manual page 64

. During feeding of HPoE +
When power is fed from the LAN connector of this unit using four wires, two wires are connected from
pins 7 and 8 of CN5001 to the HC-51 board through an SY-416 board.
A feeding line is connected to IC5001. Before the power is turned on, IC5001 certifies the physical layer
of HPoE between feeding hubs.
When power is fed from the hubs, the internal switch of IC5001 is turned on and 50 VDC is output be-
tween pins 12 and 9. Like during feeding of 24 VAC, a voltage is stepped down using IC5002 to generate
12 VDC.
During feeding of HPoE +, IC5003 is started and a power of 24 V is internally output.
Temperature control block
A temperature sensor of _15dC consists of TH5504 and IC5506. The voltage at pin 1 of IC5506 becomes
0 V when _15dC is reached. After logic is inverted using Q5522, a control signal is transferred from
CN5001 to a PS-858 board through PH5001 so as to control the camera power.
A temperature sensor of 0dC consists of TH5501 and IC5501. When 0dC or less is reached, Q5525 is
turned on and RY5501 is driven. Heaters are then turned on.
There are two heaters. The heater connected to CN5502 is connected to a 24 VAC line through RY5501.
For the heater connected to CN5506, the power system is switched using RY5502.
The heater connected to CN5506 is connected to a 24 VAC line during feeding of 24 VAC and connected
to a 24 VDC system during feeding of HPoE +.
During feeding of 24 VAC, both heaters are driven. During feeding of HPoE +, only the heater connected
to CN5506 is driven
A temperature sensor of _10dC consists of TH5503 and IC5504. The 5-pin connector of IC5504 is shifted
from 0 V to 5 V when _10dC is reached. The AC/DC converter on the PS-858 board temporarily stops
when a pulse is generated using IC5503 by transition of a level and when Q5504 is turned on for a fixed
time. A camera is then rebooted.
Detection of fan failure
Fans are always driven in 12 VDC.
Fans contain a stop detection signal. The base of Q5512 becomes 0 V when even one of the two fans
stops. The logical state is isolated using PH5501 and output from pin 2 of CN5701.
4-6. TM-61 Board
Factory-setting switch
A reset switch (S802) is used to return a system to the factory-setting state. An internal parameter is set to
the factory-setting state when the power is turned on after S802 is switched to the reset position. After
reset, return the internal parameter to the ordinary position.
4-8 (E)
SNC-WR632C/WR602C