GE Corometrics 126, Руководство по обслуживанию

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7-20 120 Series Maternal/Fetal Monitor Revision B
2015590-001
Calibration: Trimline Tocotransducer Calibration
Trimline Tocotransducer Calibration
The Corometrics Trimline tocotransducer must be calibrated using the following
procedure for use with the 120 Series Monitor.
Equipment Required
Refer to “Chapter 14, Trimline Tocotransducer Calibration” for part numbers.
„
Digital voltmeter: DM501 or equivalent with x1 probe or leads
„ Corometrics Common Mode Rejection (CMR) Test Jack (Refer to Figure 7-4 .)
„
Calibrated 120 Series Monitor
„ Anti-static Wristband
„
Static-Free Work Surface
„ Screwdriver or potentiometer adjustment tool
„
52.5 gram weight
„ Sealing tape
„
Torque seal
Procedure
During this procedure, refer to Figure 7-5 for the location of potentiometers in the
Trimline tocotransducer.
NOTE:
When performing this procedure, keep in mind that due to the nature of the
circuitry in the Trimline Tocotransducer, there is a stabilization time of
approximately two seconds for any output voltage. After adjusting a
potentiometer, verify that the output has stabilized prior to taking a voltage
reading.
1. Remove the nameplate and sealing tape from the top cover of the Trimline
Tocotransducer.
2. Set the GAIN and ZERO CTR potentiometers in the tocotransducer fully
counterclockwise.
3. Set the ZERO TRIM potentiometer to its mid-position—approximately six
turns from fully counterclockwise.
4. Locate TP6 and TP2 or TP3 (ground) on the FECG/UA Board in the 120 Series
Monitor.
5. Connect the positive lead of the digital voltmeter to TP6; connect the negative
lead to TP2 or TP3.
6. Apply power to the 120 Series Monitor; then plug the CMR Test Jack into the
monitor’s front panel
UA
connector.
7. Measure the voltage at TP6 and record the value.
8. Replace the CMR Test Jack with the tocotransducer to be calibrated.
9. Place the tocotransducer on a flat surface so that the button is face up, then
center the 52.5 gram weight on the button.