DFM digital mass flow meter
InterfaceAll features of the flow meter can be accessed via the local four button keypad and LCD. The digital interface operates via RS485 (optional RS-232 available) and provides access to applicable internal data including: flow, temperature, pressure reading, auto zero, totalizer and alarms settings, gas table, conversion factors and engineering units selection, dynamic response compensation and linearization table adjustment.
The analog interface provides 0 to 5Vdc or 0 to 10Vdc or 4 to 20 mA outputs for flow, pressure and temperature (jumper selectable).
Auto ZeroThe DFM supports automatic sensor zero offset adjustment which can be activated locally via keypad or remotely via digital interface. The auto zero feature requires absolutely no flow through the meter during auto zero process. Provisions are made to either start, stop or save the current auto zero value via digital commands.
TotalizerThe total volume of the gas is calculated by integrating the actual gas flow rate with respect to time. Both keypad menu and digital interface commands are provided to:
- set the totalizer to ZERO
- start the totalizer at a preset flow
- assign action at a preset total volume
- start/stop totalizing the flow
- read totalizer
Totalizer conditions become true, when the totalizer reading and the "Stop at Total" volumes are equal.
Flow AlarmHigh and Low gas flow ALARM limits can be preprogrammed via keypad or remotely via digital interface. ALARM conditions become true when the current flow reading is equal or higher/lower than corresponding values of high and low alarm levels. Alarm action can be assigned with preset delay interval (0-3600 seconds) to activate the contact closer (separate for High and Low alarm).
Pressure AlarmHigh and Low gas pressure ALARM limits can be preprogrammed via keypad or remotely via digital interface. Pressure alarm conditions become true when the current pressure reading is equal or higher than corresponding values of high pressure alarm settings or equal or lower than corresponding values of low pressure alarm settings. Alarm action can be assigned to activate the contact closer (separate for High and Low pressure alarm).
Temperature AlarmHigh and Low gas temperature ALARM limits can be preprogrammed via keypad or remotely via digital interface. Temperature alarm conditions become true when the current temperature reading is equal or higher than corresponding values of high temperature alarm settings or equal or lower than corresponding values of low temperature alarm settings. Alarm action can be assigned to activate the contact closer (separate for High and Low temperature alarm).
Engineering UnitsThe flow set points, measured gas flow and associated totalizer data are scaled directly in engineering units via the front panel keypad or digital interface.
The following units of measure are supported: %F.S., L/min, L/h, mL/min, mL/h, SCFH, SCFM, LbPH, LbPM, User Defined EU.
Multi-Gas CalibrationThe DFM is capable of storing primary calibration data for up to 10 gases. This feature allows the same DFM to be calibrated for multiple gases while maintaining the rated accuracy on each.
Conversion FactorsConversion factors for up to 32 gases are stored in the DFM. In addition the provision is made for a user defined conversion factor. Conversion factors may be applied to any of the ten gas calibrations via keypad or digital interface commands.
Contact ClosureTwo sets of dry contact relay outputs are provided to actuate user supplied equipment. These are programmable via local keypad or digital interface such that the relays can be made to switch when a specified event occurs (e.g. when a low or high flow, pressure or temperature alarm limit is exceeded or when the totalizer reaches a specified value).
Leak Integrity1 x 10
-9 sccs of Helium maximum to the outside environment.
DFM literature model DFM thermal mass flow meter catalog page(s)
DFC literature model DFC thermal mass flow controller catalog page(s)
Digital and Analog Flow Meters Catalog Full line Digital and Analog Flow Meters, Controllers, Valves and Accessories Catalog
DFM Communication Utility DFM Communication Utility Software Version: 2.0.0.2 (Build 0.0.0.2)
DFM Control Terminal Software DFM Control Terminal Software (Version 1.02)
Windows XP
Rotameter Catalog Full line Rotameter and Valves Catalog
DFM Digital Mass Flow Meter Operating Manual DFM Operating Manual - TD0501M Rev. D, Sep-2015
Calibration Services Calibration Services