Revision C 250cx Series Maternal/Fetal Monitor 4-33
2036947-001
Maintenance: Strain Gauge Transducer Test
The UA value shows the default setting.
The UA mode shows TOCO.
The recorder prints the messages UA REF and TOCO on the strip chart paper.
5. Apply gentle pressure to the tocotransducer diaphragm and verify that the UA
value responds to the pressure input. Increasing force should produce an
increasing value and vice versa.
6. Place tocotransducer upside down (diaphragm up) and level. Place a 52.5 g
weight (part # 2003005-001) on the center of the diaphragm and record the
resulting UA value.
7. Verify the difference between the default setting and the 52.5 g reading is
15± (2.0 mmHg (±kPa). Units are relative and scaled to match IUP units
configured in Pressure Units system default.
8. Remove the tocotransducer from the monitor’s UA input connector. Verify the
following on the monitor:
The UA value and INOP are both blank.
The recorder stops printing the uterine activity trace.
The recorder prints the message UA INOP on the center margin of the strip
chart paper after approximately 20 seconds.
Strain Gauge Transducer Test
1. Inspect a strain gauge as follows:
Unscrew the plastic dome from the transducer and check for any cracks or
contaminants on the transducer.
Visibly assess the condition of the cable, strain relief, and the connector
pins.
2. Connect the strain gauge to the UA input connector on the front panel of the
250cx Series Monitor. Verify the following on the monitor:
The UA value may read negative numbers indicating baseline pressure is
off scale. In this case, the recorder prints the message BASELINE PRESSURE
OFFSCALE on the bottom of the UA scale on the strip chart paper.
The UA mode is IUP for intrauterine pressure.
The recorder prints the message IUP on the center margin of the strip chart
paper after approximately 20 seconds.
3. Depress the monitor’s UA Reference button and verify the following on the
monitor:
The UA value is 0 mmHg (0 kPa).
The recorder prints a continuous line at 0 mmHg (0 kPa) on the strip chart
paper.
The recorder prints the message UA REF on the bottom two lines of the top
grid of the strip chart paper.