Calibration Frequencies

How Do Frequencies Work?

By definition, frequency is the number of occurrences of a repeating event per unit of time.  In Calibration Control (our Calibration Management Software), the Frequency is the interval of time between required Calibration or Maintenance Events of any given piece of test Equipment. 

Choose Calibration Frequency Select Maintenance Frequency

Frequency Fields

There are four fields involved in the Frequency functions in the Calibrations tab of an Equipment record.  And these four fields function the same in the Maintenance tab of the Edit Equipment dialog:

  • Last:  Enter the date of the last event.
  • Next:  Due date of the next required event.  This auto-calculates based on the chosen frequency and units.
  • Frequency:  Select a frequency from the combo-box list.  Available frequencies are described further down.
  • Units:  Calculates Next Date automatically based on the number of units selected.  The Unit field box may be disabled with certain frequencies, (e.g., Yearly or Monthly), because these have an inherent unit value.
Equipment Calibration Frequency

Calibration Frequencies

The following are all the available Frequencies in Calibration Control where 'n' is the number value in the Units field.  An asterix* next to the frequency name is further described below.

Frequency Name Frequency Description
Biennial Every 2 years
Bi-Monthly Every 2 Months
Bi-Weekly Every 2 Weeks
Cal Not Required No Due Date . . . Not Calibrated
Daily Every Day
Days Every n Days
Manual Set the Next Calibration (Due Date) manually
Month End Every n Months due on the last day of the month
Month of* Every n Months due at any day within the calculated month. 
Month Start Every n Months due on the first day of the month
Monthly Every Month
Months Every n Months
Next Use No Due Date . . . Next Use
Not Calibrated No Due Date . . . Not Calibrated
Quarter of* Every 3 Months due at any day within the calculated n month. 
Quarterly Every 3 Months
Reference Only No Due Date . . . Reference Only
Semi-Annual Every 6 Months
Undefined No Frequency Defined
Use Count Calibrate every n uses where n = Units.  Refer to the Check In/Out dialog to check tools out and automatically increment its tracked number of uses.
Use Days Calibrate every n days where n = Units.  Refer to the Check In/Out dialog to check tools out and automatically increment its tracked number of days of usage.
Use Hours Calibrate every n hours where n = Units.  Refer to the Check In/Out dialog to check tools out and automatically increment its tracked number of usage hours.
Week of* Every n Weeks due at any day within the calculated week. 
Weekly Every Week
Weeks Every n Weeks
Yearly Every Year
Years Every n Years

Week of | Month of | Quarter of

Unlike the many Frequencies that calculate due dates on specific days, there are special Frequencies that calculate the week of, month of, or quarter of when a tool is due for attention.  These Frequencies are affected by two field settings in the General tab of the Options dialog: First Day of Week and the Due Date 'Week/Month of' Offset

By default, the "First Day of Week" is set to whatever is standard on your operating system and Calibration Control uses the system-defined first day of the week.  Otherwise, you can manually define the first day of the week in the Options settings, which determines the due date for calibrations using the 'Week of' Frequency.

Special Frequencies

"Month of" Example

  • Frequency:  Month of
  • Last Calibration:  04/27/2019
  • Units:  12
  • Offset:  Next
  • Calibration Due:  04/27/2020
  • Default Label Display:  Due Month of Apr-2020

How the math works . . .

  1. Calculate 12 Months after Last Calibration, which yields 04/27/2020
  2. The Offset is set to Next [Month] so the Due Month jumps to the next Month, which yields 05/1/2020

"Week of" Example

  • Frequency:  Week of
  • Last Calibration:  06/01/2019
  • Units:  30
  • Offset:  Next
  • First Day of Week:  Monday
  • Calibration Due:  07/01/2019
  • Default Label Display:  Due Week of 07/01/19

How the math works . . .

  1. Calculate 4 Weeks after the Last Calibration, which results in 06/29/2019.
  2. Since the Offset is set to Current [Week] and the First Day of Week is set to Monday, the Monday of the current week results in a due week starting on 07/01/2019.

"Quarter of" Example

  • Frequency:  Quarter of
  • Last Calibration:  05/16/2021
  • Units:  4
  • Offset:  Next
  • First Day of Week:  Monday
  • Calibration Due:  07/01/2022
  • Default Label Display:  Due Quarter of 07/01/22

How the math works . . .

  • Q1 First Quarter: January 01 – March 31
  • Q2 Second Quarter: April 01 – June 30
  • Q3 Third Quarter: July 01 – September 30
  • Q4 Fourth Quarter: October 01 – December 31
  1. The Due Date Offset setting is Next [Month of], so calculating three-month periods with 'Quarter of' Frequency at even zero Units jumps to the next quarter for a due date. 
  2. Calculation of 4 Units for 'Quarter Of' Frequency from the Last Calibration date under these settings results in a due quarter starting 07/01/2022.

Quick Start Video

The link below is a short video about using Calibration Frequencies in Calibration Control (our Calibration Management Software).  While the software appearance differs between versions, the general concept is demonstrated in the following video.  


Last Updated:  14 February 2022