Sentry Sample Sentry II Low Pressure - Flow Rates; Flow Rate Settings; Blowdown Time; Setting Duration

Sentry Sample Sentry II 17
Flow Rates
Figure 10. Flow Rates
Flow Ra tes
Blowdown
1500 cc/min
Figure 10 shows the ow rates setup screen. The rst set point displayed is the blowdown
ow 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 nished changing the
displayed set point, press the ENTER key to display the next set point. After setting the last
ow rate, pressing ENTER returns the unit to the setup screen. The following ow rates can
be programmed:
Blowdown: This ow rate is used during the Blowdown state. During this time, the entire
sample ows to the grab sample, preventing ow to analyzers. This mode is designed to
ush the sample at a slightly higher ow rate than the sample state.
 NOTE
EPRI recommends a blowdown velocity no greater than 125% the normal sampling velocity.
Sample: This ow rate is used during the Sample state. During this time, sample is allowed
to ow to analyzers.
Shutdown: This ow rate setting is used to determine when the system should shut
down. When the total ow 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 ow rate to 0 cc/min, and
disable the Shutdown pressure setpoint.
Blowdown Time
Figure 11. Blowdown Time
Blowdown Time
hh :mm: ss
0:45 :00
Figure 11 shows the blowdown time setup screen. This setting controls the duration the
system stays in blowdown after startup. To change the seconds eld, use the ▲ and ▼
keys. To change the minutes eld, hold the ENTER key while using the ▲ and ▼ keys. To
change the hours eld, 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.