Dräger 8000 IC - Detailed Description of Function Blocks of Unit PCB

6141.22X Incubator 8000 IC/SC/NC
Function Description
09.99 Page 31 of 49
- Mains transformer
- Sensor to monitor number of revolutions at impeller (inductive fan monitoring)
- Semiconductor relay for galvanically separated triggering of air heating and humidifier
- PCB Unit:
a. mains auxiliary transformer for mains connection
a. mains connection relays
b. safety relays for heatings and O2 valves
c. fuses for mains input and internal supply voltages
The unit forms the intersection between supply voltage and secondary side of the electronics.
A voltage higher than + 33 V is not supplied to the other incubator components.
3.1.1 Detailed description of function blocks of Unit PCB
3.1.1.1 Mains connection
Incubator 8000 is connected to the mains via the auxiliary transformer L1 to which the mains
relays K1 and K5 are connected at the secondary to +12 V. The relay is connected via pins
X1/1 and X1/27 via the standby switch at the front panel. Through the relay contacts the mains
voltage is supplied to the consumers.
3.1.1.2 Cutoff relay K2 for heating
Relay K2 is a safety relay to cut off the mains voltage supply of the air and humidifier heating.
3.1.1.3 Cutoff relay K3 for 02 valves (Inc. 8000 IC only)
Relay K3 is a safety relay to cut off the supply voltage of the 02 valves.
3.1.1.4 Cutoff relay K4 for +24 V
Relay K4 is a safety relay to cut off simultaneously the supply voltage of the semiconductor
relays, of the air and humidifier heating and of the 02 valves.