Schiller AT-1 Mode D'emploi page 51

Service Printout Service Printout Service Printout
Service Printout Service Printout
• Uref +
• Uref -
• Udif
• Uoff
• Calib
Electrode dc offset
TPH TEMP
EPROM
This gives the value of the reference voltage used in the multiplexer circuit on the ECG
Amplifier. The value of the reference voltage is 2000 mV ±20 mV.
This is a negative reference voltage used on the ECG Amplifier board. The value of this
voltage should be -2000 mV ±20 mV.
This is the sum of the two reference values above (Uref+and Uref-). This value must be
4000 mV ± 20 mV.
This is the value of the offset voltage on the multiplexer circuit. This value should be
between + 150 mV and - 150 mV.
This value is the Udif value divided by 4. The nominal value is 1000 ±5 mV.
This gives the voltage drop in the patient cable and can indicate any faults in the
patient cable or patient electrode. The value given is the dc voltage between the left
leg electrode and all other electrodes. The measurements obtained will indicate any
cable short circuits or open circuits. The measured voltage value will depend on where
the electrodes are connected. The voltage readings that can be expected are as
follows:
• With patient connected: ± 100mV
• With patient simulator connected: ± 20 mV. This will depend on the patient simulator
used and must be taken as a flexible measurement.
• With all electrodes shorted together: ± 20 mV
• No patient cable connected: -350 to -450mV
This is the measured ambient temperature that the processor uses to correct print quality.
This reading should be ambient temperature ± 5
This is the checksum for the EPROM. Its value varies from one software version to another.
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AT-1 User Guide Art. No. 2.510171 g
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