Sierra InnovaMass 240i Series, Instruction Manual, Page: 70 / 115

70
You can press the exit

several times to climb back up to the main menu level or press


to
proceed to the next Sub-Menu called Units Per Pulse.
Totalizer (Sub-Menu): Units Per Pulse
Use this menu to select the units per pulse. Navigate to the “Units Per Pulse” screen. Use Table 5
for guidance if necessary.
Note the maximum frequency at which the totalizer can count is 1
pulse per second or 1 Hz. This puts a limit on the units per pulse and makes resolution
dependent on flow rate.
For example, assume the maximum flow rate is 100 scfm and you want the totalizer to pulse
every 5 scf. Since the flow is 100 scfm, it will take 5/100 minutes, or 3 seconds to totalize 5 scf.
That is acceptable since the totalizer takes longer than 1 second to accumulate scf.
Assume that now you want more resolution, so you would like the totalizer to pulse every 1 scf.
Since the flow is 100 scfm, it will take 1/100 minutes, or 0.6 seconds to totalize 1 scf. Since the
instrument’s totalizer is 1 Hz, it can’t pulse any faster than a maximum rate of once per second (1
Hz).
In this example, the best units per pulse would be 1.7 scf; that is over the 1 HZ maximum
sampling rate.
Press enter

and the units will begin flashing. As in previous examples, use the

buttons to enter the desired value, and the enter key

to save the value.
Press

to proceed to the Totalizer On/Off screen or press the exit

several times to climb back
up to the main menu level.
Totalizer (Sub-Menu): Totalizer On/Off
Use this menu to turn the totalizer “On” or “Off.” Use Table 10 for guidance if necessary. Press
enter

and the variable will begin flashing. As in previous examples, use the

buttons to
select “On” or “Off,” and press enter

to save the value.
The units of the totalizer are the same as entered in the units menu (minus
the time since this is an accumulation and not a rate).
Units per pulse
1.700000
Totalizer On/Off
On