The ROD4-A control unit is designed to control up to four MFCs or MFMs, and it is operated in combination with analog or digital MFCs.  The unit can be controlled via the keypad on the front panel or using a PC via the RS-232 or RS-485 interface.  On the front panel, a separate display field for each channel shows the set points and actual values, as well as various operating conditions.  Individual channels can be switched on or off separately without changing the set points, and the unit also has an adjustable ramp function.

The ROD4-A unit is easily used as a tabletop unit or as an insert in a 19" rack.  The main voltage supply can be between 90 and 240 VAC.  MFCs are connected exclusively via standard 9-pin, sub-D connectors.  Potential-free relay contacts for the four control channels can be connected via two 15-pin, sub-D connectors.  If the current gas flow exceeds or falls below the specified tolerance range of the particular set point, the corresponding relay is activated automatically.