Siemens Servo Screen 390 Repair

The Siemens Servo Screen 390 was manufactured by Siemens between the years 1995 and 2000. It is meant to function as a display for the Siemens Servo Ventilator 300/300A or the Siemens Servo Ventilator 900C/E. The Servo Screen does not control the ventilator. It can display system information or patient condition.

The Servo Screen 390 displays patient information on an elector-luminescent, mono-chromatic screen. It receives inputs with its pulse-generator, which is the knob at the bottom right of the machine, which can be turned 360 degrees or clicked in. It has a memory card at the rear of the device, at the top left side. This memory card holds the operating system and application software for the Servo Screen 390. The Servo Screen 390 has 6 ports; a keyboard port (for service use only), a printer port, a communications port (for serial communication with other devices), a ventilator port, a CRT port (for an external monitor), and a power port for the power supply. The Servo Screen 390 has a 3.6V internal battery that is used to back up the computer setup stored in the CMOS-RAM/SRAM. If the battery is disconnected, factory settings will be loaded on next boot.

The Servo Screen 390 is identified by the “Servo Screen 390” text in the top right hand corner of the front of the device. There is also a sticker that states the serial number and model number (Servo Screen 390) at the bottom right corner of the device at the rear. A serial number of 10000 or lower means that the device uses an Intel 80486SX microprocessor, while a serial number of 10001 or higher denotes the more modern Pentium 166 processor.

Siemens Servo 300 Ventilator
Siemens Servo 300A Ventilator 
Siemens Servo 900C Ventilator

Type: Electro-luminescence;
Display size: 10 inches;
Resolution: 640 x 480 pixels;
Monochromatic;
Brightness: Selectable in 5 levels;
Graphical interface: VGA

Width: 330 mm (excluding support arm);
Depth: 88 mm (excluding control knob and support arm);
Height: 252 mm (excluding support arm)

4.3 kg (9.5 lbs) including support arm

Supported waveforms:
Flow-Time;
Pressure-Time;
Volume-Time;
CO2 concentration-Time2, 3;
Supported loops:
Volume-Pressure;
Pressure-Volume;
Flow-Volume;
Flow-Pressure;
CO2 concentration-Expiratory volume2, 3;
Supported parameters;
Peak Pressure;
Pause Pressure;
PEEP;
Total PEEP (the actual PEEP level if measured in lung periphery);
Mean Airway Pressure;
Expired Minute Volume;
Inspired Tidal Volume;
Expired Tidal Volume;
Breathing Frequency;
I:E Ratio;
Inspired O2 Concentration;
Static Compliance1;
Dynamic Characteristics;
Inspiratory Resistance;
Expiratory Resistance;
End Expiratory Flow;
End Tidal CO2 Concentration 2,3;
CO2 Tidal Production 2, 3;
Ineffective Tidal Volume2;
Effective Tidal Volume2;
Airway Dead Space3;
Alveolar Tidal Volume3;
Alveolar Ventilation3;
Number of Apneas 4;

Numerical values from the Servo Ventilator 300/300A are updated breath by breath, numerical values from Servo Ventilator 900C/E are updated every 15 seconds.

Source: Bemes Online Respiratory Sales

Bemes Online Respiratory Sales

Servo Screen 390 Service Manual