Dräger Babylog 8000SC, Technical & Service Manual, Page: 26 / 155

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Dräger Medical AG & Co. KGaA 6173.3
Function description Babylog 8000
4.10 ROM Test
During operation, the ROM area used is summed up per byte in a long word variable (long word = 32 bits)
which is compared to the check sum stored in the ROM. If the check sums do not match, an error
message will be displayed.
4.11 RAM Test
During operation the RAM area used is tested with a simple algorithm. By writing 55 hex or AAhex in each
cell every bit is checked for settability and resettability.
4.12 Temperature Monitoring
A temperature sensor measures the internal temperature of the Babylog. If the temperature is not within
the range of –20 °C to 75 °C, an alarm will be generated. If the temperature is too high, a message will
inform the operator about a possible failure of the fan.
4.13 Relay and Valve Monitoring
An excess-current monitoring function is integrated into the trigger electronics of the valves. The excess-
current monitoring function is tested after switching on Babylog. If a valve is switched on and operated
with the operate voltage for an excessive period of time, the excess-current monitoring function responds
within a specific time.
The relay which enables de-energizing of the whole pneumatics assembly is also tested once after power-
on. For this purpose, the relay is switched on and off once and the voltages at the relay contact are
measured.
During operation, the system checks whether the voltage at the relay contact corresponds to the switching
condition.
4.14 Battery Monitoring
Babylog has a rechargeable Nicd battery for power failure alarms.
The battery is recharged automatically during operation and its charge checked periodically.
An error message is displayed if the voltage is too high or too low.
4.15 Flow Measurement Monitoring (Babylog 8000/ Babylog 8000 plus)
During operation, the flow sensor is checked for correct functioning, freedom of damage and intact
contacts.