FAQ: Technical update for PROFIBUS on Alicat

Which products can have PROFIBUS installed?

PROFIBUS protocols are an option on most of Alicat Scientific’s flow and pressure instrumentation:

  • Mass flow controllers and meters (MC and M Series)
  • Pressure controllers and gauges (PC and P Series)
  • Whisper™ low pressure drop products (MCW and MW series)
  • Liquid meters and controllers (LC and L Series)

Which products do not include PROFIBUS as an option?

  • BASIS and EPC OEM instruments
  • Class 1 Division 2 area instruments
  • Portable instruments

What are the specification changes to an Alicat Instrument, when PROFIBUS is included?

Electrical connectorsDB9 female (top connector) + DB9 male (side connector)

Communications and power Mass flow meter or mass flow controller with PROFIBUS
Digital Outputs PROFIBUS DP (top connector) + RS-232 (side connector)
Analog Outputs None
Display Options None
Supply Voltage 7 to 30 Vdc
Supply Current 40 mA on flow and pressure meters. 250-750 mA (depending on valve) for flow and pressure controllers.


Which connector do I use to power the PROFIBUS device?

The DB9 male (side connector) is used to provide power to the device unless it was ordered with the Power over PROFIBUS (POP part number) option in which you will use the DB9 female (top connector).

Do I still have a choice of gases and gas mixes on PROFIBUS equipped instruments?

Alicat gas instruments with PROFIBUS possess our full Gas SelectTM list of gas calibrations. It does not include the COMPOSERTM firmware.

How fast are communications with an Alicat instruments equipped with PROFIBUS?

The device supports all standard PROFIBUS baud rates, 9.6 Kbps up to 12 Mbps. The device will auto detect the baud rate when powered up.

What is the notification indicator LED?

The LED will light up green if proper PROFIBUS communication is established.

Can I update my existing instruments to possess PROFIBUS?

Both electronic hardware and firmware requirements needed to install PROFIBUS mean that it must be ordered on new instruments, and cannot be retrofitted to existing Alicat products.

What DP version is the Alicat device?

The device can be used with any PROFIBUS-DP master which supports any of these versions, but currently we have only implemented cyclic “V0” type commands on Alicat devices.