Sentry Sample II Low Pressure Installation, Operation & Maintenance Manual page 17

Flow Rates
Figure 10. Flow Rates
Figure 10 shows the flow rates setup screen. The first set point displayed is the blowdown
flow rate. To adjust the set point, use the ▲ and ▼ keys. To change the set point in counts
of 100, hold the MENU key while using the ▲ and ▼ keys. When finished changing the
displayed set point, press the ENTER key to display the next set point. After setting the last
flow rate, pressing ENTER returns the unit to the setup screen. The following flow rates can
be programmed:
Blowdown: This flow rate is used during the Blowdown state. During this time, the entire
sample flows to the grab sample, preventing flow to analyzers. This mode is designed to
flush the sample at a slightly higher flow rate than the sample state.
 NOTE
EPRI recommends a blowdown velocity no greater than 125% the normal sampling velocity .
Sample: This flow rate is used during the Sample state. During this time, sample is allowed
to flow to analyzers.
Shutdown: This flow rate setting is used to determine when the system should shut
down. When the total flow is less than this set point and the PRV is full open, the system
shuts down.
 NOTE
If the desire is for the system to never shut down, set the Shutdown flow rate to 0 cc/min, and
disable the Shutdown pressure setpoint .
Blowdown Time
Figure 11. Blowdown Time
Figure 11 shows the blowdown time setup screen. This setting controls the duration the
system stays in blowdown after startup. To change the seconds field, use the ▲ and ▼
keys. To change the minutes field, hold the ENTER key while using the ▲ and ▼ keys. To
change the hours field, hold the MENU key while using the ▲ and ▼ keys. To return to the
setup screen, press the ESC key.
 NOTE
To disable blowdown, set the blowdown time to 0:00:00 .
Sentry Sample Sentry II
F l o w
B l o w d o w n
1 5 0 0 c c / m i n
B l o w d o w n
h h : m m : s s
0 : 4 5 : 0 0
R a t e s
T i m e
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