MFC

Bronkhorst MFC

Connectivity

BronkhorstMFC is a source block (with an optional setpoint sink) that reads live flow, temperature, frequency, and alarm data from a physical Bronkhorst mass flow controller connected over the browser's Web Serial API. Communication uses the PROPAR protocol with automatic ASCII / Enhanced Binary mode negotiation. On connection the block identifies the instrument, reads its full-scale capacity and engineering unit, and scales flow readings from percent-of-full-scale into real units automatically.

Use this block to bring a live MFC into a BlockWerk control diagram — for example, to close a pressure or concentration control loop using actual hardware measurements. The block also writes a flow setpoint back to the instrument, either from its setpoint parameter or from the on-canvas input field, allowing real-time hardware actuation from within the simulation.

Inputs & Outputs

Direction	ID	Label	Type	Status
← Out	`measure`	Flow (%)	number	Output
← Out	`fmeasure`	Flow (Value)	number	Output
← Out	`temperature`	Temperature (°C)	number	Output
← Out	`frequency`	Frequency (Hz)	number	Output
← Out	`alarm`	Alarm Status	number	Output

Parameters

Parameters	Label	Type	Default	Description
`nodeAddress`	Node Address	number	`3`	PROPAR node address of the instrument (typically 3 for directly connected single instrument)
`baudRate`	Baud Rate	select	`115200`	Serial baud rate. Must match the instrument configuration. 115200 gives best throughput.
`pollRateMs`	Poll Rate (ms)	number	`10`	Target poll interval in ms. The bus fires immediately when RTT exceeds this — so 0–10ms gives maximum speed (~40 Hz at 115200 baud). Increase to reduce CPU load.
`enableLegacyPorts`	Enable Legacy Ports	boolean	`false`	Enable polling for legacy Measure and Alarm ports. Disable this to maximize bus speed when using fMeasure.
`setpoint`	Setpoint (%)	number	`0`	Flow setpoint as percentage of full scale (0–100%).

Usage Examples

Live flow measurement fed into a closed-loop controller

BronkhorstMFC ──► [Flow (Value)] ──► PIDController → [measured]
  nodeAddress: 3
  baudRate:    115200
  pollRateMs:  10

Monitor flow and temperature on a scope

BronkhorstMFC ──► [Flow (Value)]    ┐
              ──► [Temperature (°C)] ├──► Scope

Multi-instrument bus scan and auto-configure

Use the SCAN BUS button on the block face to discover all PROPAR devices. Selecting multiple instruments automatically places additional BronkhorstMFC blocks on the canvas, one per instrument.

Remarks & Best Practices

Source block with setpoint output: All measurement outputs are on the right side. The setpoint is written to hardware via the block face input or the setpoint parameter — there is no left-side setpoint input port.
Web Serial API required: Only available in Chromium-based browsers (Chrome, Edge, Brave, Opera). The block displays a "Browser Not Supported" warning in Firefox and Safari.
Automatic flow scaling: After connection the block calls identify() to read the instrument's full-scale capacity and unit. Flow values on fmeasure and measure ports are then automatically multiplied by (capacity / 100) and reported in engineering units.
Selective polling: Only ports with outgoing connections are polled, minimising bus traffic. fmeasure and temperature are always polled to keep the block face display live.
fmeasure vs measure: When both ports are active, measure (16-bit integer) is skipped in favour of fmeasure (float, higher precision). Enable legacy ports only when the instrument does not support process 33.
Parameter Explorer: While connected, the wrench button opens a full PROPAR register browser, allowing any DDE parameter to be added as a named output port.
Tunable params: pollRateMs and setpoint can be changed live from the Properties panel during an active simulation.

Related Components

BronkhorstEmulator: Emulates a Bronkhorst instrument on a serial port for software-in-the-loop testing without physical hardware.
ExternalInput: Inject synthetic flow values into a control diagram without hardware.