Welch Allyn Spot Vital Signs Service Manual page 69

Welch Allyn, Inc. Spot Vital Signs Service Manual
Revision A
Repair Test
General Unit Test
A-D Noise Test
The A-D Noise Test is defined as the amount of noise on the Unit A-D pressure channel, over a 1 second sample time
while 0.0 mmHg is applied to the Unit pressure port. The maximum limit is 0.050 mmHg.
Leak Test
Leak Test is defined as the amount of pressure drop that is recorded over a 15 second interval with a 100cc volume
attached to the Unit pressure port and that volume having a stabilized pressure of 250 mmHg. The limit is 5 mmHg
max
Inflation Test
Inflation Test is defined as the amount of time the Unit pump can inflate a 250cc volume from 5 mmHg to 210 mmHg.
The limit is 7 seconds, max.
Dump Test
Dump Test is defined as the amount of time it takes the Unit to deflate a 500cc volume from 260 mmHg to less than 15
mmHg. The limit is 10 seconds.
Pneumatic Calibration
Note: The Unit can not be calibrated if the internal temperature is beyond 32'C.
The unit will be calibrated with 0 and 250 mmHg applied to the pressure port with the following algorithm:
-Adjust the pressure calibration 'offset' value with the following formula.( (Last autozero pressure
value + current unit pressure) * 16384 /(pressure offset correction value + pressure gain
value)). The pressure offset value must be -15384 to 15384.
-The Unit must be able to successfully perform an autozero.
-Adjust the pressure gain value until the unit pressure deviation from the applied pressure is less than
mmHg. Continue to utilize the following formula until the pressure is less than 0.1
pressure / unit pressure) * pressure gain value. The pressure gain value must be
When the pressure transducer calibration is performed(only when successful), a calibration signature will be stored in
the Unit memory. The calibration signature can be any of up to four printable characters.
When the pressure transducer calibration is performed(only when successful), the date and time of that calibration will
be stored in the Unit memory.
Pneumatic Accuracy Test
Note: This test will be conducted in the configuration mode of the Spot Vital Signs.
Perform Autozero before the start of this test. The Pneumatic Accuracy test is defined as the comparison of the Unit
pressure measurement and applied pressure at 0, 50, 175, and 275. The maximum limit for the 0 reading will be +/- 1.0
mmHg, all others +/- 3.0 mmHg.
Valve Control Test
With a 100 cc volume connected to the Unit pressure port and pressurized to 160 mmHg, give Unit commands to open
the valve for 10 mSec., 15 mSec., and 25 mSec. And record each pressure drop. The pressure drops will be 4 to 12
mmHg, 4 to 15 mmHg, and 4 to 25 mmHg respectively.
correction
mmHg. (applied
1000 to 31767
Page 62 of 64
0.1