Zimmer A.T.S. 2000, Operators & Service Manual

Page: 15 / 32

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3.4.4 CALIBRATION
CALIBRATION SHOULD BE PERFORMED EVERY 6
MONTHS, OR AFTER ANY UNSCHEDULED MAINTE-
NANCE.
Calibration of the A.T.S. 2000 Tourniquet consists of a
series of set-points from which the microprocessor can
calculate the correct pressure readings by linearizing the
pressure from the set-point voltages. These set-points are
made by pressurizing the individual transducers to a prede-
termined pressure then allowing the microprocessor to read
the voltages at those pressures (set-points). The set-point
voltages are stored in nonvolatile memory and used when-
ever pressure is calculated.
The unit software contains an instruction set for the Cali-
bration Mode that is independent of the normal operating
software. To enter the Calibration Mode, turn the unit on,
then press and hold the Second Pressure Increase (+) and
Decrease (–) touch-switches until “CUFF” “CAL” is dis-
played.
EQUIPMENT REQUIRED:
A. Calibration connecting hose
B. Calibrated mm Hg pressure meter
C. Adjustable pressure source, 0 to 700 mm Hg
Caution: The following steps must be taken in the exact
order to calibrate the unit. Failure to do so may result in
incorrect pressure readings while the unit is in opera-
tion.
1. Connect the calibration connecting hose, pressure
gauge and adjustable pressure source as shown in Fig.
1.
2. Turn the unit on and enter the Calibration Mode.
3. Set the zero point in the main cuff by pressing the Main
Cuff “INFLATE” and “DEFLATE” touch-switches at the
same time. A tone will be heard letting you know that
the zero point has been entered.
4. Set the zero point in the second cuff by pressing the
Second Cuff “INFLATE” and “DEFLATE” touch-switches
at the same time. A tone will be heard letting you know
that the zero point has been entered.
NOTE: Steps 3 and 4 must be performed with the Calibra-
tion Connecting Hose disconnected from both Cuff Sense
Ports.
5. Adjust the main cuff set point by pressing the Main Cuff
Time (+) touch-switch once. The Main Cuff Time display
should be showing 50.
6. Adjust the second cuff set point by pressing the Second
Cuff Time (+) touch-switch once. The Second Cuff Time
display should be showing 50.
7. Insert the main cuff line with connector into the Main
Cuff Sense Port. See Fig. 1.
8. Insert the second cuff line with connector into the Sec-
ond Cuff Sense Port. See Fig. 1.
9. Apply 50 mm Hg of pressure to the input ports.
10. Set the 50 mm Hg point in the main cuff by pressing the
main cuff “INFLATE” and “DEFLATE” touch-switches
at the same time. A tone will be heard letting you know
that the 50 mm Hg has been entered.
11. Set the 50 mm Hg point in the second cuff by press-
ing the second cuff “INFLATE” and “DEFLATE” touch-
switches at the same time.
12. Repeat steps 5–11 for set points of 250 and 475.
13. Remove source pressure then disconnect the calibra-
tion connecting hose from both sense ports.
14. Return the set points to zero by pressing the time (–)
touch-switch 3 times for each cuff.
15. Press the second cuff pressure (+) and (–) touch-
switches at the same time to move into reservoir cali-
bration. The second pressure display should be show-
ing “RES”.
16. Set the zero point in the reservoir by pressing the main
cuff “INFLATE” and “DEFLATE” touch-switches at the
same time. A tone will be heard letting you know that
the zero point has been entered.
17. Adjust the reservoir set point by pressing the main cuff
time (+) touch-switch once. The main cuff time display
should be showing 250.
18. Insert the main cuff line with connector into the Main
Cuff Reservoir sense port. The Main Cuff Reser-
voir sense port is the leftmost port on the main cuff.
See Fig. 1.
19. Insert the second cuff line with connector into the
Second Cuff Reservoir sense port. The Second Cuff
Reservoir sense port is the leftmost port on the
second cuff. See Fig. 1.
20. Apply 250 mm Hg of pressure to the reservoir sense
ports.
21. Set the 250 mm Hg set point in the reservoir by press-
ing the main cuff “INFLATE” and “DEFLATE” touch-
switches at the same time. A tone will be heard letting
you know that the 250 mm Hg point has been entered.
22. Repeat steps 20 and 21 for 475 and 700 mm Hg pres-
sure set points.
23. Remove source pressure then disconnect the calibra-
tion connecting hose from both sense ports.
24. Return the reservoir set point to zero by pressing the
Main Cuff Time (–) touch-switch 3 times.
25. Press the Second Cuff Pressure (+) and (–) touch-
switches at the same time. The Main and Second Pres-
sure displays should be showing “CAL” “DONE”.
NOTE: THE “CAL” “DONE” MUST BE DISPLAYED BE-
FORE TURNING THE UNIT OFF. THE NEW SET POINTS
WILL NOT BE SAVED IF POWER IS REMOVED BEFORE
“CAL” “DONE” IS DISPLAYED.
26. Set unit to STANDBY at the ON/STANDBY (I/O) touch-
switch. Remember, this switch has approximately a
2-second delay before allowing the unit to be set to
STANDBY, so you must hold the touch-switch in.
27. Restart the unit. We recommend that you check your
calibration by following the steps in Section 2.2 step 5
“Calibration Check”.
3.4.5 LEAK TESTING
The A.T.S. 2000 Tourniquet is capable of keeping a cuff with
a substantial leak inflated. Naturally it is desirable to keep
plumbing leaks to an absolute minimum. For this reason,
a check for significant leakage is recommended at regular
intervals as well as following any service procedure.
After verifying the operation of the A.T.S. 2000 Tourniquet
per Section 2.2, connect two 24 in. (61 cm) (or larger) cuffs
which are known to be leak free to the A.T.S. 2000 Tourni-
quet System. Adjust both cuff set points to 475 mm Hg. En-
sure that all external connections are tight. Inflate the main
and second cuffs and allow the pressure to stabilize. At this
point, the unit must be set to STANDBY. Under normal use,
the unit