Calibration Test Trigger Types

Most systems are set up with multiple calibration checks (cals) that act differently depending on their specific uses. Also known as validations, cals can be triggered in one of six ways depending on the instrument or frequency of test run time.

Below is a list and explanation for each of the cal trigger types:

A – Automatic Cal

  • This cal is initiated by the data controller’s internal clock and is repeated on a preset interval. An A-type cal cannot be configured without a starting time and an interval (repeat) time.
  • A-type cals allow the data controller to output any configured physical or digital output line during the phases of the cal, which allows the controller to close and open solenoid valves for set periods of time during each phase.

E – Externally Initiated Cal

  • An externally initiated cal is started in the data controller by an input expression.
  • E-type cals allow for more versatility in logic programming, as they can be triggered by anything that closes an input. This includes a physical input wired into the back of the logger, an event program that closes a pseudo output/input at a specific time every day, a console that closes a pseudo input based upon a configured button, any many more.
  • As with the A-type cal, an E-type cal allows the controller to close and open solenoids based upon its own programming.

I – Instrument Controlled Cal

  • An instrument controlled cal is initiated and controlled by external equipment, and cannot be started or stopped manually.
  • Unlike an E or A-type cal, each phase of an I-type cal is controlled by an input expression. So long as the external instrument is closing the inputs that correspond with a phase of the cal, the cal will remain running in that phase.

U – User Initiated Cal

  • This cal is similar to an E or A-type cal, except that there is no trigger expression. A U-type cal can only be triggered manually from the logger or from StackVision. Most often a U-type cal is configured for a Linearity or CGA.
  • Once manually triggered, the cal will control cal phase times and output expressions based upon how it is configured.

L – User Initiated w/ Confirming Digital Inputs

  • The L-type cal is similar to the U-type cal in that it can be only triggered manually, however each phase must have a Confirming Input Expression configured. Each phase of the cal must have the configured input expression be true for the cal to move onto the next phase. If the input expression is not closed before the end of the phase, the validation will be aborted.

M –  Interactive (Menu) Cal

  • In this kind of cal, the user controls cal data acquisition via a menu interface. While each phase of the cal is configured to close a specific output expression, the phase length and phase data time (period of time used for the cal evaluation) are controlled by the user in a menu driven interface on the logger.

For more information about how cals are configured in your system, contact the ESC Support team.
 512-250-7901  •

If you require engineering assistance configuring calibrations in your system, contact the ESC Sales team.
512-250-7902  •


Clint Anderson, Lead Project Engineer I, ESC    Published: 6/6/2017 12:30:01 PM

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