Setpoint ramping tutorial
Alicat controllers come equipped with a setpoint ramping feature that allows them to ramp up and/or down to changes in setpoint. With setpoint ramping, you can set a maximum speed at which a mass flow or pressure controller flows until the setpoint is achieved. Setpoint ramping can be performed using either the front display or serial commands.
Setpoint ramping is commonly used to ensure safety, by ramping up pressure or flow in a controlled, observable way. Setpoint ramping can also be configured to only apply to flow/pressure in a single direction for situations where you may need to quickly zero pressure or flow during an emergency.
To enable and edit the setpoint ramp functionality on your device, follow the instructions below.
Video tutorial
Step-by-step instructions (front panel)
- Press the bottom right button for āMENUā selection.
- Press the top left button for āCONTROLā selection.
- Press the top left button for āSETPT RAMPā selection.
- Press the top left button for āDELTAā selection.
- Use the up, down, and select digit buttons to set your desired delta.
- Press the bottom right button for āSETā selection.
- Press the top right button for āTIMEā selection.
- Use the up, down, and select digit buttons to set your desired time.
- Press the bottom right button for āSETā selection.
- Press the top middle button for āTIME UNITSā selection.
- Use the up and down buttons to select your desired time units. Note:Ā This will NOT change the rate, and it will automatically update the current rate to the newly selected units.
- Press the bottom right button for āSETā selection.
Video transcript
āMy name is Marina Palese, and Iām an App Engineer at Alicat Scientific.Ā Today Iām going to show you how to set up setpoint ramping.Ā Letās get started.ā
To give a setpoint ramp to your device, weāre going to to MENU (bottom right button), CONTROL (top left button), SETPT Ramp (top left button), and from here we can set our DELTA (top left button).Ā This is how much we want the flow to change in this ramp, and we can set that to whatever value we like (ex. 100 SLPM).
At this point the display will read āCurrent Max Ramp Rate -None- SLPM/sā.
The TIME (top right button) will be the amount of delta over time.Ā Letās say we want to change 100 SLPM per one second.
At this point the display will read āCurrent Max Ramp Rate 99.99999 SLPM/sā.
And then we can set out units (top middle button).Ā Letās say we change these to hours.Ā Then, the current ramp rate will automatically adjust to whatever the time unit is.
Finally, the display will read āCurrent Max Ramp Rate 360000 SLPM/hourā.