Philips Avalon CTS M2720A, Service Manual

Page: 54 / 110

6 Preventive Maintenance and Safety Performance Assurance Tests
48
Performance Assurance Tests
Self Test
The system performs a basic-level self test when you switch it on. You hear a beep, and all the display
elements are shown for about one second, and then the display reverts to normal display mode.
Parameter Test
This tests the entire signal path from the individual transducers connected via radio frequency, through
the base station, to the fetal monitor with artificially generated test signals. We recommend you perform
this test once a day, and whenever you doubt the reliability of the measurements. The parameter test does
not test the transducers themselves, there is a separate test for this (see “Testing Transducers” on page 67).
Base station display
In this example, one US transducer and one Toco transducer are
docked. No other transducers are active.
Initial displays appear as shown. The battery indicator is lit on the
base station.
The bed label is visible on both displays.
The transducer display shows which slot is occupied.
Ultrasound
transducer display
(slot 1)
Toco transducer
display
(slot 2)
To start the test, with no transducers or alarms active:
1
Press and hold down .
The test mode remains active for as long as you keep
pressed.
Battery charging stops, and the transducers behave like normal,
active transducers. However, to differentiate between test mode
and normal operation of a registered transducer, the two-digit
numeric display in the LCD window shows the two segment
bars (
-- ) blinking.
If you remove a transducer while the parameter test is still in
progress, the transducer shuts down.
2
Each transducer transmits an artificial signal, via the
programmed RF channel, to its registered slot on the base
station.
After decoding and processing, the artificial signals are fed via
the analog connection to the telemetry interface input of the
fetal monitor. The signals coming from the base station are
then processed and displayed by the fetal monitor.
Artificial HR
signal
Signal quality
Value of artificial signal