Erbe ICC 200, Руководство по обслуживанию

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3 CIRCUIT DESCRIPTION
Art. No.: 801
16-201
0
9
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4
The following assemblies are located on the PCB:
• Output stage with driver for high HF voltage pulses
• Relay with relay control
• Feedback of actuation frequency for the CPU
ST power stage
The ST power stage is used to generate high pulses for coagulation without a cutting effect, particularly for
quick superficial coagulation.
The designation “ST” output stage is derived from the abbreviation of spray generator for TUR.
The power control and the generation of actuation pulses are found on the control board.
The actuation pulses (TSI-STE) move to the driver IC4 and then to the ST output stage transistor T1. This
operates on the output transformer UE1, the secondary side of which emits the high frequency via the
capacitors C1 and C2 as well as the relays REL1, REL2 and REL3 at the connections AE and NE. The
emitted high frequency is fed to the outputs via the Senso-board.
The capacitors C1 and C2 serve as a high-pass for suppression of faradic effects and are also an additional
protection in isolating the patient circuit from the equipment circuit. Due to the necessary high electric
strength, two relay contacts each are switched in series.
The output relay is actuated via the relay driver IC7 which receives its actuation signals via the bus and the
target memory IC6 (D-flipflop).
The ST power stage is supplied with voltage that is switched with relay REL19 from the power module via
the connectors J2 and J3.
The integrated counter IC1 subdivides the frequency of the actuation signal of the ST output stage to a low
frequency, so that the frequency in the CPU can be determined by means of a counting loop.
Since the processor prescribes the actuation frequency, it receives feedback in this way as to whether the set
and actual values agree. This is important since the output power of the ST power stage is controlled via the
repetition frequency of the individual pulses.
ST power stage
Slot J6