Fukuda Denshi VaSera VS-1500, Service Manual

Page: 48 / 216

Chapter 5
Maintenance
5-16
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5.3.10.3 Test Parameters and Criteria
●
0 point check
This test indicates the pressure value at atmospheric pressure when no connection is made
to the air connectors.
Criteria: A pressure value of 0 mmHg should be indicated.
●
Safety mechanism [Pressure upper limit]
Pressurize the 500ml tanks to measure the pressure when the hardware overpressure
safety mechanism is activated.
Criteria: The quick exhaust valve should activate at a pressure of 320 ±10 mmHg.
●
Inflation time [Inflation time]
Pressurize the 500ml tanks and measure the time it takes to raise the pressure from 0 to
300 mmHg.
Criteria: 9 s or less
●
Air leakage (Leakage) [Air leakage]
Raise the pressure in the 500ml tanks to 300 mmHg and let it stabilize for 15 s. Then
measure air leakage during a 1-minute period.
Criteria: The pressure drop should be 6 mmHg/min or less.
●
Quick exhaust [Exhaust characteristics]
Pressurize the 500ml tanks and open the quick exhaust value to measure the time it takes
to lower the pressure from 260 to 15 mmHg.
Criteria: 10 s or less
● Slow-leak valve performance [100% open]
Raise the pressure in the 500ml tanks to 300 mmHg, add a 100% control pressure voltage
to the flow control valve for testing. Then open the valve and measure the exhaust speed
until the pressure drops to 180 mmHg.
Criteria: a speed in the 20 to 60 mmHg/s range
●
Slow-leak valve performance [75% open]
Raise the pressure in the 500ml tanks to 300 mmHg, add a 75% control pressure voltage to
the flow control valve for testing. Then open the valve and measure the exhaust speed until
the pressure drops to 180 mmHg.
Criteria: a speed of 10 mmHg/s or more.
●
Safety mechanism [Time limit]
Apply a constant pressure of 10 mmHg or more to the 500ml tanks to test the hardware
safety device that controls time of pressure application.
Criteria: The quick exhaust valve should activate within 130 ±10 s.
The time value should be 8 ±1 s when [High Speed] is engaged.