Ac/Dc Power Supply Unit; Batteries; Frame Unit Fan; In-Built Recorder Unit - GE Datex-Ohmeda S/5 Series Technical Reference Manual

2.5 AC/DC Power Supply Unit

The universal AC/DC power supply provides an isolated 15.5 V supply for the S/5 Compact
Monitor. The power unit is attached to the Frame Unit by four screws and a power-D25
connector.
The cooling air for the AC/DC unit is from the Frame Unit fan through cooling holes in the Frame
Unit back plate. The power unit generates a load signal, which is read by the PMB board in the
Frame Unit.
The AC/DC power supply is protected by an overvoltage protection. If the output voltage
increases over 17V, the protection is activated and the AC/DC power supply unit does not
return to normal operation until the power cord is briefly disconnected.

2.6 Batteries

There are two NiMH batteries attached to the bottom of the Frame Unit. The PMB board
connects one of the batteries to be the power source, if no power is received from the AC/DC
power supply.
The battery charging is controlled by PMB. The normal charge current for the batteries is
170mA RMS. When the batteries are full, the charging is continued by a 10mA current (trickle
charge) to avoid self-discharge of the batteries.

2.7 Frame Unit Fan

The Frame Unit Fan is used for cooling the Frame Unit electronics, the modules and the AC/DC
power unit. The fan is controlled by the PMB. The rotation speed of the fan is adjusted
according to the frame temperature and AC/DC power unit load. At monitor start-up, the fan is
briefly run at full speed to ensure its operation.

2.8 In-built Recorder Unit

The recorder unit is located in the Side Frame Unit, and it is connected to the Connector Board
PMB-REC with a small connector board and 12-pin flex-strip cable.
External Communication
Communication with the monitor Central Processing Board takes place via the Connector
Board PMB-REC, PMB, the Connector Board to Display Unit and the Display Unit DC/DC power
unit.
The communication uses +5 V CMOS level RS232 serial interface with an RS485 reset.
Reset The differential RS485 reset from the module bus generates a Recorder Unit reset signal on the
Recorder Board. The Recorder Board also generates a power-up-reset, whose time constant is
approximately 0.1 second. The Recorder Unit reset signal is therefore active when either the
Module Bus RS485-reset or the power-up-reset is active.
+5 V priority The recorder unit supply voltage, +15 VREC is switched on after +5 V is present.
Frame Unit for F-CM(C)1 (Rev. 05), F-CM(C)REC1 (Rev. 01)
Document no. M1144958-001
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