Do you have to use the Brooks 0254 Secondary Electronics with your new mass flow controller (MFC)?

• It needs power (usually 24VDC; sometimes +/- 15 V).
• It needs a set point (quite often 4-20 mA or 0-5 V).
• It needs to send its output (4-20 mA or 0-5 V) to something.

When I hook up a mass flow controller on my dining room table (while my wife is at work), I need secondary electronics to do these three things. Brooks 0254 secondary electronics is a great power supply. It can power up to four Brooks devices (Quantims, mass flow controllers, pressure transducers, cylinder scales… anything needing 24 volts to run.).

The secondary electronics can generate set points for four devices and even do batching and blending of the four channels. Of course, the secondary electronics has a display. In fact, there are eight lines of display.

The default is for setpoint and actual flow to be shown for each of the four channels.

So, secondary electronics are great!

But, if you, the customer, have a power supply somewhere else, and you have a computer or PLC that can send and receive current or voltage signals, you do not need our cool little box. You will have to use six wires from our 15-pin connector for power, setpoint in, and flow signal out.

You can use more wires if you want to use the valve override function or the alarm diagnostics. (Most don't.)

Are you sorry you asked the question yet? Everything above is based on an mass flow controller, but what about a mass flow meter? Flow meters require only two of the three things mentioned above.

They need power, and they will send a flow signal out to your computer/PLC. As long as you have a power supply and the ability to accept 4-20 mA or 0-5 volt signals in your PLC (usually something called an analog card is required in the PLC), then you do not need the Brooks 0254.

I could go on, but I hope this little lesson clears things up.