(e) Trigger the oscilloscope sweep to begin when the motor turns ON
and adjust variable resistor R36 to set the ON-time circuit for a five second sweep.
Close verification can be made using a storage-type oscilloscope. Adjust to within plus
or minus 0.5 seconds.
(f) Trigger the oscilloscope to begin when the motor turns off and
adjust variable resistor R35 to set the OFF-time circuit for a five-second sweep. Adjust
to within plus or minus 0.5 seconds. A storage-type oscilloscope simplifies
measurement.
NOTE:
Steps (e) and (f) above may be monitored at various points. For simplicity
and convenience, the positive-voltage motor input should be used, and the
oscilloscope triggering slope set for the ON circuit, then reset for the OFF
circuit.
2-5.
PREVENTIVE MAINTENANCE PROCEDURES
Preventive maintenance checks and services (PMCS) are provided by the
equipment operator (EO) who regularly operates the equipment and a medical
equipment repairer who provides repair and troubleshooting capabilities. Table 2-1
shows the PMCS tasks, who performs them [equipment operator (EO) or medical
equipment repairer (MER)], and the frequency of performance.
PREVENTIVE MAINTENANCE
PROCEDURE
EO
MER
Clean item (remove dust, lint, rust, etc.)
D
A
Properly store accessories
AO
Change filter
Z
Visually inspect and perform operating tests
BO
Lubricate casters with graphited oil
Q
Perform leakage-current tests
S
Estimated average annual man-hour
Z
requirements
Abbreviations:
AO = after operations; D = daily;
Q = quarterly; S = semiannually;
A = annually; Z = as necessary;
BO = before operation.
Table 2-1. Preventive maintenance checks and services procedures.
CAUTION:
Do not overfill vacuum bottles. If simultaneous ac recharging and
external 12vdc operation is being employed, ensure the external 12vdc
MD0365
2-13