Detection Algorithm Timers; Baseline Update Timer; Arrival Detection Period; Velocity Gathering Period - ETC Sasquatch User Manual

5.3 Detection Algorithm Timers

The following detection algorithm timers help set the filtering and data gathering rates. By default they
are configured to detect the arrival and velocity of a plunger. They are made available to fine tune the
operation of the sensor for other applications.

5.3.1 Baseline Update Timer

This is the frequency at which the baseline is updated.

5.3.2 Arrival Detection Period

This is the rate at which the magnetic signal is sampled while waiting for a plunger to arrive.

5.3.3 Velocity Gathering Period

This is the rate at which the magnetic signal is sampled once the plunger has been detected.

5.3.4 Velocity Gathering Timeout

This specifies how long we gather data after an arrival has been detected before we stop to calculate
the velocity.

5.3.5 Velocity Calculation Timer

This specifies a time that the Sasquatches uses to process all other operations once the velocity has
been calculated before it begins looking for the plunger departure.

5.3.6 Departure Detection Period

This is the rate at which the magnetic signal is sampled when waiting for the plunger to depart. The
plunger is not considered departed until we see 5 consecutive periods pass without detecting the
plunger.

5.3.7 Re-Initialize Timer

This timer specifies how long to wait after the plunger has departed before re-initializing the sensor.

5.4 Lubricator / Spring Wear Settings

The Sasquatch provides alarms and statistics for monitoring spring wear due to hard plunger arrivals.
This functionality is useful for monitoring well safely and for maintenance scheduling

5.4.1 Plunger Mass

The mass of the plunger in thousandths of a pound (x1000 lbs) or grams. This is required in order for the
Sasquatch to calculate accurate kinetic energy of the arriving plunger as it hits the lubricator. If this
information is not provided, the velocity-based lubricator / spring alarms will still operate.

5.4.2 Hard Arrival Velocity Threshold

If the velocity of the plunger exceeds this threshold a hard arrival has occurred. If enough consecutive
hard arrivals occur an alarm flag will be set. Hard arrivals can also trip the Cumulative Hard Arrival Alarm
and the Cumulative Kinetic Energy Alarm
Associated Alarms: Consecutive Hard Arrival Alarm, Cumulative Hard Arrival Alarm, Cumulative Kinetic
Energy Alarm
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