Using the Sasquatch with the ALiEn2 Expert controller allows the surface velocity to be read each cycle and be used for safety and/or optimization. This article explains the steps required to connect, configure, and troubleshoot this setup.
There are several steps to installing the Sasquatch as well as some important notes. Please read carefully. For any referenced manuals, Click Here.
- Install the Sasquatch as per the Sasquatch User’s Manual ensuring that it is low on the lubricator so that the plunger will pass by the sensor.
- Using the Installation and Integration Best Practices App Note with ETC Vision will allow you to ensure that the Sasquatch is picking up the plunger arrivals and calculating velocities correctly.
- Wire the Sasquatch to the PAS and COM 2 inputs on the back of the controller.
- On the controller, navigate to install>Inputs>PAS and change to Velocity
- On the next screen, Test Velocity Sensor allows you to see the plunger Velocity, Confidence Code, and Plunger status. If you test after an arrival you should see a valid velocity and a confidence code of 2 – 8.
If you see do not get valid readings on the test screen or the the status screen, you should resolve this issue before moving forward.
Note: RxError (RXE) reported on the status screen indicates that the controller and Sasquatch are not communicating. The A and B on COM 2 are mislabeled on some Controllers and may need to be swapped to rectify this.
Use of Surface Velocity for Safety
- Under install>Well Setup, change the Danger Fast Source (DngrFstSrc) to Surface Velocity (Srf Vel). This will use the surface velocity for both dangerous trips and fast trips.
- Set the Dangerous Trip Velocity and Fast Trip Velocity. A Dangerous Trip will shut the well in on one Dangerous Arrival, while Fast Trips will shut in after a number of consecutive Fast Arrivals occur (found in Alarms).
Dangerous Time and Fast Trip Time will be based on the velocity and well depth but will not be used unless there are issues getting a valid velocity and the controller is forced to fall back.
Optimizing off of Surface Velocity
- In install>Optimize, choose the Optimize Type and then set the Velocity Source to Surface Velocity.
- In install>Well Setup set the Rise Velocity or Rise Time (these are connected via well depth) to ensure the controller waits long enough for the plunger to arrive regardless of surface velocity.
- Set the Target Surface Velocity that you would like the controller to achieve.
- You must also set the Target Average Velocity or Target Rise Time (which are linked by Well Depth) as this is used for a fall back in case the surface velocity is not calculated or read.
When using a Freecycle plunger, it is falling and rising during the Rise Time of the controller. This means that the Rise Time as well as the Target Rise Time (or Target Average Velocity) from above must be set appropriately to account for the round trip, not simply rising from the bottom of the well.