Fukuda Denshi VaSera VS-1500, Service Manual

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Chapter 6 Troubleshooting
6.4 ECG
No. Symptom Check Remedy
1 Error message “Lead off”
appears. Check if the lead cables are broken
or are short-circuited by some
other signal. Replace the lead cable.
Check if the lead cables are broken
or are short-circuited by some
other signal. Replace the lead cable.
2 Lead off could not be
detected.
In lead off condition, check the AD
converter input to the lead that is
not detected.
(
☞
10.1.1.C4)
The input amplifier is defective if
–2.5 V cannot be obtained.
Check whether the lead cables are
loose. Connect the lead cable correctly.
Check if the lead cables are broken
or are short-circuited by some
other signal. Replace the lead cable.
3 Recording of a lead is in
the baseline state.
Check the AD converter input to
the lead that is not detected.
(
☞ 10.1.1.C4)
If the signal does not change with
waveform input, the input amplifier
is defective.
Check whether the F3 or F5 fuses
are blown.
(
☞
10.1.2.B1)
Replace blown fuses. 4 Recording of all leads is in
the baseline state.
Check the power supply of the
ECG-AMP.
C478: +5V (
☞
10.1.1.B4)
The ECG-AMP power supply is
defective.
Check for hum contamination. Set the hum filter to the electric
frequency of the local area.
Check if the instrument is
grounded. Ground the instrument securely via
the power cord or grounding
conductor.
5 Noise contamination
Check clip electrodes and
echopads. Apply clip electrodes securely and
replace echopads.
6-8
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