Mindray DC-68, Service Manual

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4-14 Product Principle
4.5 Power Supply Unit
The power supply function is shown as below. The power supply unit can be divided into AC and
DC from the aspect of power supply transfer
flow.
AC-DC Module
AC Interface
Module
Assistant Output
Module
DC-DC Module
AC input
Control System & Ultrasound Functions
AC output
AC output
Printer
DC supply
AC Unit
control
PHV Module
DC Unit
power
Power Unit
Devices
control control
AC input
AC input
AC output
Figure 4-12 Schematic diagram of power supply unit
DC includes DC-DC module, PHV module and battery assembly.
AC includes AC-DC module, assistant output module and AC interface module.
Closely related to ultrasound services, the voltage circuits in DC part are quite large, in which the
performance also occupies high-performance. The coupling of DC part keeps tight as well. At the
same time, the space arrangement also keeps close to ultrasound service. However, AC, to some
extent, couples little with ultrasound service. The volume is comparatively larger, which may lead
away from ultrasound service.
DC and ultrasound services are located inside the main unit box above the base. Whereas, AC is
located inside the power supply box below the base. Two parts are connected by cables. The output
path for heavy current should take pressure drop, the security, fool-proofing and the reliability into
consideration.
Figure 4-13 The connection of power supply box and main unit box