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INSTALLATION AND OPERATING INSTRUCTIONS
CAUTION:
Non-technical alarm conditions will terminate automatically when the alarm condition that was
generating the alarm signal is corrected.
PRESSURE ALARMS
A pressure alarm will occur when the pressure in a cuff is more than 15 mmHg from the pressure set-point. It is also
possible for a cuff to have a leak that is substantial but which the unit can compensate for by continual pumping. This
type of leak could be due to a:
•
Pin hole in a cuff bladder.
•
Defective o-ring.
•
Loose pneumatic fi tting.
This type of leak could progress into a total failure of a cuff to hold pressure. To alert the operator that a substantial
leak is present, a pressure alarm is declared when this type of leak is detected. If a pressure alarm occurs, and the
displayed pressure is not more than 15 mmHg from the set-point, then this type of substantial leak has been detected
and all cuffs and pneumatic fi ttings should be checked for leaks.
ADVANCED LEAK DETECTION
The
A.T.S.
4000TS has an Advanced Leak Detection feature that automatically monitors an infl ated cuff in real-time
and observes potential leaks that may be occurring in the cuff or hoses. Advanced Leak Detection determines the
magnitude of the leak. During cuff regulation, pressure is maintained within the set-point limits and the system’s leak
detector will monitor the rate of air fl ow into the cuff. The rate of air fl ow to the cuff is monitored for a period of time
which takes into account normal transient pressure disruptions such as range-of-motion checks. A determination of
the magnitude of leakage, that disregards transient disruptions, is produced by the Advanced Leak Detector.
Any leakage of air from either cuff or the connection between cuff and device will cause a reduction in cuff pressure.
The system will maintain the cuff set-point pressure automatically. The rate at which the system must replenish air lost
due to leakage in order to maintain the cuff pressure at the set-point is proportional to the magnitude of the leak.
Advanced Leak Detection determines the magnitude of leakage by monitoring the level of the pressure increase
signals during the cuff infl ation period and then estimating the magnitude of leakage as a function of the level of the
pressure increase control signal throughout the infl ation time period.
The magnitude of leakage determined by Advanced Leak Detection is indicated to the user in the Stats report as
“LEAK DETECTED.”
Advanced Leak Detection is capable of differentiating between the transient, such as range-of-motion checks, and the
sustained activation of valves caused by a leak.
Advanced Leak Detection can detect low leak. This type
of leak is unlikely to trigger an alarm, but is indicative of
a potential problem with a cuff, hoses, or the pneumatic
connection between a cuff and device. Advanced Leak
Detection won’t trigger an alarm, but rather report the
potential problem in the Stats report.
If Advanced Leak Detection has indicated a leak, the user
should take action by leak testing the cuff and hoses. Leaky
cuffs and hoses should be replaced.