401-405 SERIES
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3.10. Flow Totalization
The Hastings 400 Series flow meters are capable of providing a value for the “total amount of gas” that
has passed through the flow meter since the last time the totalization function was reset. This value can
be used to determine for example, the amount of gas used to fill a chamber or drawn from a supply
vessel. To initialize the totalization function, reset the totalized flow value to zero using the S36 digital
command as shown in the example below. All subsequent flow readings are added over time and stored
as the totalized flow value. The totalized flow value can be read by querying the flow meter digitally as
in the example below. The totalized flow is reported in the flow units chosen for the active gas without
the time unit. For example, if the flow units are standard liters per minute, the totalized flow is reported
in standard liters; if flow units are standard cubic feet per hour, the totalized flow is reported in standard
cubic feet.
Example: For a 100 slm FS flow meter, to first reset/start the flow totalization function and then later read the
value using RS-232,
Computer transmits: {S36=0}
This resets the totalized value to zero and starts the totalization function. At some point later in time:
Computer transmits: {S36}
HFM flow meter replies: {45.7}
This is interpreted as a total gas amount of 45.7 standard liters has passed through the meter since the flow
totalizer was started.
3.11. Additional Digital Capabilities
The Hastings 400 series flow meters have a wide selection of other functions, operating parameters, and
values that can be reported and configured via digital communications such as the calibration date, the
instrument temperature, the number of hours that gas has been flowing, etc. See the Software Manual
for detailed information on these additional digital features.
CAUTION
Accessing the rotary encoder requires removing the enclosure
front plate. Care must be taken when reinstalling this plate to
ensure that the sealing gasket is properly positioned and the
fasteners are secure to maintain an IP65 compliant seal.
NOTE
The software command to change the active gas record will not
be executed unless the rotary encoder is set to a number greater
than 7. However, the software query will return the current active
gas record number even when it has been set by the hardware.
