POWER

The IRIDIUM platform requires 24 VDC power. Various power adapters are also available for use as needed. The unit cannot be powered through the USB port.

SIGNAL INPUTS/OUTPUTS

All units can be completely controlled through the on-board touchscreen. In addition, full remote control is available through the RS485 serial connection, and limited control is available through the USB port. An optional expansion module also adds analog I/O functionality (EAA module).

SOFTWARE UPDATE

The IRIDIUM platform can easily be customized through downloadable firmware updates via the micro-USB port. The factory can provide custom software packages with unique configurations to match specific applications or process conditions.

ELECTRICAL CONNECTIONS

A 15-pin D-SUB connector provides all power and signal connections to the IRIDIUM, with the exception of the USB port. Various adapters and hubs are available to adapt the connector to wiring terminals or other interfaces.

DISPLAY

All IRIDIUM packages incorporate a 3.2” [ 81 mm ] color touchscreen that provides readouts of current flow rate, total flow, and system status. The touchscreen can also be used to configure the IRIDIUM settings, adjust set-points and alarms, and troubleshoot errors. The touchscreen can become a digital keypad for simple numeric value entry when needed.

AVAILABLE OPTIONS & UPGRADES: ANALOG I/O MODULE (EAA)

Enables the IRIDIUM to receive and transmit analog signals such as 4-20 mA, 0-20 mA, 0-10 VDC, or 0-5 VDC. All signals are fully isolated.

AVAILABLE OPTIONS & UPGRADES: ALARM OUTPUT MODULE (EBA)

Enables the alarms that are built-in to the IRIDIUM to be transmitted externally via solid-state relay contacts.

AVAILABLE FLOW PATH BLOCKS

Currently, McMillan offers one type of inlet/outlet block, one flow sensor block type, and one valve block type.

MALE FLARE INLET/OUTLET BLOCKS (F601)

To facilitate connections to the fluid systems, the F601 inlet and outlet male flare blocks are machined from PTFE and are available in 1/4”, 3/8” and 1/2” sizes (examples in Figure 1a). Male flare connections accept flared PFA tubing and require flare nuts to secure (available as accessories).

Male flare to NPT adapters are available to adapt 1/4” male flare connections to 1/8” FNPT (P/N 861-370) and 3/8” male flare connections to 1/4” FNPT (P/N 861-380). These adapters are illustrated in Figure 1b.

Two F601 blocks are required for each working IRIDIUM configuration. The inlet and outlet can be different sizes as required by the application.

MICROTURBINE FLOW SENSOR BLOCK (A601)

McMillan’s microturbine wheel technology (explained more on the microturbine technology page) utilizes the Pelton turbine wheel concept. This design allows for the use of a miniature turbine wheel supported by a very small sapphire shaft. The shaft is held in position by two maintenance-free bearings. Due to the light weight of both the wheel and the shaft, the microturbine wheel is virtually suspended in the flow path.

DIAPHRAGM PROPORTIONAL CONTROL VALVE BLOCK (B601)

To provide responsive control of flow rate, the B601 applies pressure to a large diaphragm that proportionally opens and closes the fluid pathway. This diaphragm is actuated by a precision engineered cam driven perpendicular to the diaphragm with the use of a stepper motor. As the stepper cam extends, it applies more pressure to the diaphragm.

In addition to inputs provided by the flow sensor block, the B601 is also able to predictively estimate cam location based on set-point changes. This reduces response time to achieve large changes in flow rate based on large changes in the set-point.

The B601 is designed exclusively for proportional control. It is not designed for a positive shutoff. Contact the factory or an authorized representative for details on using the IRIDIUM to control an external shutoff valve for dispense applications.

...HOW DOES A FLOW CONTROLLER WORK?

Flow controllers use an integrated flow rate sensor and control valve to regulate flow rate, regardless of inlet pressure fluctuations. A flow control set-point is provided by the user via the touchscreen, or remotely via an electronic signal. The controller then adjusts the integrated valve as needed to maintain the desired flow rate.