Equipment overview: Theory of operation
2000966-542D Dash 3000/4000/5000 2-43
Patient data storage
Static RAM backed up by a lithium battery soldered onto the processor/
power management PCB stores patient data.
Time and date
A patient monitor on the network maintains time and date for at least 
five years. Time is accurate to within one second in ten hours. The clock 
is synchronized with a time master on the optional CARESCAPE 
Network.
Calibration data
Calibration factors for NBP and CO
2
 are stored in non-volatile memory 
on the DAS board.
Calibration factors for the analog output signals are stored in non-
volatile memory on the processor/power management PCB.
Error log
Input and output errors are retained in static RAM backed up by a 
lithium battery soldered onto the processor/power management PCB. 
Contents are retained for at least five years, provided that you exercise 
caution when you handle the board to prevent inadvertently discharging 
the battery (e.g. when you ship the board for problem diagnosis).
Optional thermal printer
The patient monitor uses the same 50-mm thermal printer module that 
is used in the PRN 50 stand-alone printer. It prints up to four waveforms 
at chart speeds ranging from 0.1 to 50 mm/s. The printer software is 
loaded independently from the patient monitor’s software.
In the patient monitor, the printer module limits its current consumption 
to stay within its allocated system power budget.