Diva Metering Module - Dräger Medical Zeus Technical Documentation Manual

Zeus
5.3 DIVA metering mod-
ule
5133.001
The actuation valves for the left and right side metering modules are con-
trolled by a valve driver. When the microcontroller is in Reset mode the power
is cut to all valves. To minimise the power loss from the valves, the voltage is
switched down from 18 V to 7 V by means of an integrated circuit (step-down
regulator) once the valves have been actuated. In the event of an error, the
valves are shut off in groups by way of an additional integrated circuit located
in the supply voltage line (high-side switch).
The heaters in the supply module are controlled by PWM-capable switching
transistors. When the microcontroller is in Reset mode the power is cut to all
heaters. In the event of overheating, the heaters are shut off by the tempera-
ture monitor by way of a high-side switch.
The Supply Module PCB has 3 interfaces.
– By way of the CAN interface the PCB communicates with the other sys-
tems.
– By way of the Debug interface the software can be updated.
– By way of an optical interface the PCB communicates with the two meter-
ing modules.
When detected, each metering module is connected to the 24 V supply by
way of a relay controlled by the processor. The processor also controls 2 fans
by way of relay in the same way.
The Supply Module PCB also performs a number of monitoring functions.
The monitoring functions include, for example, measuring the operating volt-
age, the heating current and the temperature, as well as monitoring the
metering modules to set them to a safe state in the event of an error.
8 LEDs signal the following states:
– LED1 on = CPU reset, operation mode
– LED2 on = CPU reset, operation mode
– LED3 on = CPU reset, operation mode
– LED4 on = CPU reset, fast Task
– LED5 on = CPU reset, slow Task
– LED6 on = no overheating by heater
– LED 7 on = dead man's signal left channel on
– LED8 on = dead man's signal right channel on
The metering module is an anaesthetic-specific unit. In order to provide users
with maximum possible flexibility, the metering module is of plug-in design
and so can be exchanged by the user. When the metering module is not con-
nected to the supply module the gas inlet and outlet of the metering module
are closed by the spring-loaded closure valves (25) and (72)
digital valves and the flow control valve are also closed.
Function Description
(Figure 17). All
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