Using the gas totalizer on a mass flow controller

Using the gas totalizer on a mass flow controller

Mass flow totalizing is used for measuring how much accumulated mass of a particular gas (or gas mixture) has been flowed in a process, where a meter alone will measure the rate of flow at any given moment. Alicat mass flow meters have a totalizer function option, which can be great for monitoring processes.

On a mass flow controller, the totalizer option can be used to dispense a set amount of gas, since the controller is equipped with a high precision, fast-response valve. Mass totalizer dispensing is used in bio-reactors, micro-flow dispensing in pharmaceutical testing and production, fermentation, and even high altitude ballooning.

See below for instructions on how to navigate the menus using the built-in display and user interface for changing parameters and resetting the totalizer. Alicat mass flow instruments can also be controlled through serial communications or industrial protocols.



Step-by-Step Instructions

  1. Press the bottom right button for “TOTAL” selection.
  2. If desired, press the top right button to toggle the largest displayed value between totalized flow and time.
  3. If desired, press the bottom middle button to “RESET” the totalizer.
  4. Press the bottom left button for “BATCH” selection.
  5. Use the up, down, and select digit buttons to set your desired batch size.
  6. Press the bottom right button for “SET” selection.

Note:  The batch will begin immediately with a non-zero setpoint.

“Hello, I am Michael Whiteside, an application engineer here at Alicat Scientific. In this video I’m going to show you how to use the totalizer functionality of an Alicat device. Now let’s get started.

In order to correctly navigate through the totalizer functionality on an Alicat device, we will first hit total/menu (bottom right button). The totalizer screen comes up here.

We see we have the current setpoint (top middle button), the current flow rate (top right button), and total/timer (top left button).

Now we currently have total selected which will tell us the total amount of gas that has flown through the device as the totalizer has been running.

This timer (top left button) tells us how long the totalizer has been running, and we can reset that here (bottom middle button).

Now the totalizer comes with a very cool function called the batch mode here (bottom left button), and we can tell the device to flow a specific amount of gas into the system.

Say we would like to flow five standard liters, we can change that here (top left button for ‘up’, top middle button for ‘down’, top right button for ‘select digit’). Hit set (bottom right button), and the device will feed specifically five standard liters into the system.

That is how to properly use the totalizer functionality.”