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

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cannot be set to STANDBY with a non-zero pressure value
displayed in the cuff(s). However for leak testing pur-
poses, a bypass feature has been incorporated. Press the
ON/STANDBY touch-switch until the alarm message
“CUFF” “NOT” “DEFL” appears. Release the ON/STANDBY
touch-switch and within 5 seconds of the alarm discontinu-
ing, press and hold the ON/STANDBY switch again. The
switch must be held in for an additional 10 seconds before
the unit will be set to STANDBY.
NOTE: During the 10 seconds, the alarm will continue to
sound a high pitch tone, the alarm silence lamp will be lit
and the alarm message “CUFF” “NOT” “DEFL” will be dis-
played. The alarm cannot be silenced by the alarm silence
switch.
After 10 minutes, turn the unit back on. Operation will
resume under cuff inflated start-up conditions (see sec-
tion 2.5 part 3 for explanation). Cancel the alarm using the
ALARM SILENCE push-button. Display both main and sec-
ond pressure points be activating either PRESSURE touch-
switch and view the current (New) pressure set point. The
set point is always displayed with an asterisk in the far left
position. The current set point for either cuff should be at
least 400 mm Hg or more. Values less than this should be
traced and corrected. The first connection to check should
be the connections of the cuffs. Different cuffs and/or cuff
hoses may be tried to determine if the leak is internal or
external of the unit.
3.4.6 BATTERY VOLTAGE AND BATTERY SERVICE
NOTE: This section assumes that the unit has been
plugged in and the battery charging for at least 24 hours.
The rear case must be removed to measure battery volt-
age. See Section 3.3 ACCESS TO PARTS and be sure to
follow cautionary statements.
A. Battery Voltage Check
Be sure the unit is unplugged. Attach a volt meter to the
battery plug (P6 on the CPU board). The battery voltage
should not be lower than 24 volts while in this off state. If,
after 1 minute, the voltage reads less than 24 volts, the
integrity of the batteries should be suspect and they should
be replaced.
B. Battery Service
The two 12-volt sealed lead acid batteries are charged us-
ing the latest lead acid charging technology. The charging
circuit is active anytime the unit is plugged into an accept-
able
AC (~) outlet and the batteries are installed. The charger
automatically sequences through several charge states
based on the battery voltage and charging current condi-
tions. Based on a charger test, the best charge mode is
selected. No maintenance is required of the battery charg-
ing circuit.
The life of the batteries depends on the type of service
and the storage method. Battery replacement will need to
be more frequent with continued cycles of deep discharge
and/or storage in a high temperature environment. Infre-
quent short-term use of the batteries and storage in a
room-temperature environment will result in maximum life.
It is recommended that the batteries in the A.T.S. 2000 be
replaced annually. The A.T.S. 2000 should be connected
to
~
power 24 hours before initial use.
3.5 UNSCHEDULED MAINTENANCE
The A.T.S. 2000 Tourniquet is designed with several specific
self-test features to assist in fault isolation. These features
are designed to show a message in PRESSURE and TIME
displays. The meaning of these messages are delineated in
Tables 2.1 and 2.2.
Another mode of failure that might occur is where the high
pitched tone occurs that cannot be silenced by the ALARM
SILENCE push-button. The valves and pump will be dis-
abled‚ which seals off the cuff(s) to prevent pressure loss.
The displays may show random characters. Should this
occur, the Watch Dog Timer circuit of the safety processor
has detected a problem. The microprocessor may not be
executing reliable instructions and is not able to display the
correct failure message. This failure mode, and all others
giving a “FAIL” message, might be cleared by cycling the
ON/STANDBY touch-switch.
The calibration error message (CALM, CAL2 or CALR) may
be due to faulty circuitry or may simply indicate the need
for calibration. The Watch Dog Timer (WDT) error message
may be due to a faulty Watch Dog Timer circuit or improper
microprocessor timing.
3.6 EXPECTED TEST POINT READINGS
To expedite unscheduled maintenance, Table 3.1, Ex-
pected Test Point Readings, has been incorporated into this
manual. This table, as well as Table 3.2, Troubleshooting,
should give a qualified technician a good starting point from
which to locate and repair most problems that could occur
during the life of the unit.
3.7 TROUBLESHOOTING GUIDE
To aid in unscheduled maintenance, Table 3.2 delineates a
number of possible malfunctions that could occur with the
unit. The most likely causes are shown for each symptom.
While it is not practical to enumerate every conceivable
malfunction and all possible causes, the table will assist in
isolating the most common problems.
Expected readings on both the CPU and power supply
boards are shown in Table 3.1. All measurements are to be
made at room temperature with the cuffs disconnected, and
the unit connected to AC (~) power. All voltage measure-
ments are with respect to ground and are to be made with
the unit on.