/
Performing NATA Balance Calibrations

Performing NATA Balance Calibrations

QEST Platform 4.92 and 4.93
Applies to QESTLab

The following article describes how to set up balance calibration tasks and use calibration worksheets for balances in line with NATA General Accreditation Guidance - User checks and maintenance of laboratory balances.

Contents

Setting Up Calibration Tasks

Before completing a balance calibration, calibration tasks need to be created for each balance. In Australia, at least four tasks should be created: a task for entering data from a full calibration report usually issued by an external calibration organization, a limit of performance calculation task, a repeatability check task, and a single-point check task.

Prerequisite Permissions

The user's role permissions must include the general right Calibrate Equipment and access to the following balance calibration documents, found under the role's Equipment Documents.

  • Balance Calibration Data Entry
  • Balance Limit of Performance
  • Balance Repeatability Check
  • Balance Single-Point Check

If the calibration document for a task cannot be found, seek assistance from the system administrator. 

Full Calibration Task

  1. Navigate to the desired balance and open the equipment screen.
  2. In the Calibrations & Checks frame, select the Add new calibration and check task button 
  3. Create a new task for entering data from full calibration reports,
    • In the Details frame
      • Name:  Calibration Data Entry, or similar.  
      • Worksheet drop-down, select the Balance Calibration Data Entry document.
    • In the Schedule frame, configure the schedule so that this task is performed every 3 years (or as specified by the laboratory's accrediting body).

Limit of Performance Task

  1. In the Calibrations & Checks frame, select the Add new calibration and check task button 
  2. Create a new task for calculating the limit of performance.
    • In the Details frame
      • Name: Limit of Performance, or similar.  
      • Worksheet drop-down, select the Balance Limit of Performance document.
    • In the Schedule frame, configure the schedule to a Once on task.

Repeatability Check

  1. In the Calibrations & Checks frame, select the Add new calibration and check task button 
  2. Create a new task for calculating the for the repeatability check.
    • In the Details frame
      • Name: Repeatability Check, or similar.  
      • Worksheet drop-down, select the Balance Repeatability Check document.
    • In the Schedule frame, configure the schedule to Recur every 6 months.

Single Point Check

  1. In the Calibrations & Checks frame, select the Add new calibration and check task button 
  2. Create a new task for calculating the for the single-point check.
    • In the Details frame
      • Name: Single-Point Check, or similar.
      • Worksheet drop-down, select the Balance Single-Point Check document.
    • In the Schedule frame, configure the schedule to Recur every 1 month (or however often it's desired).


Performing the Full Calibration Data Entry

Data entered on the calibration data entry worksheet is used by the other worksheets, so should be performed first. This screen is a results-only screen and allows a user to enter the results from a NATA, or equivalent, endorsed calibration certificate. NATA requires a three yearly full calibration and describes the data that needs to be recorded.  

  1. Start the task by clicking Start Calibration.
    • If the calibration task is already in progress, click Open Worksheet to view it. The Balance Calibration Data Entry worksheet will appear.

  2. Enter the data from the full calibration.
    • Enter the number of Readings first and then the data from the calibration report.
    • Results can be entered for single range balances (same resolution across the entire range of operation), dual-range and poly-range, as explained under 1148618021.
    • Other balance calibration documents will import data from the full calibration worksheet.
    • Enter the Scale Range in the format x to y.  For this example,  0 to 6000. The Scale Range values entered will be available for selection on other balance calibration worksheets for this particular balance.

Performing Calibrations for Multiple Scale Ranges

Balances may perform differently over their range of operation (scale range). 

Multiple copies of the Balance Calibration Data Entry worksheet can be added for different ranges. For example, if a balance performs differently for masses from 0 to 600g than from 600 to 6000g, then 2 copies of all the screens should be made (2 separate equipment tasks for each). In the Scale Range (g) field in the Details frame, enter 0 to 600 for the first task, and 600 to 6000 for the second task. The worksheets will be grouped together by name.

When adding other calibration screens the Scale Range (g) drop-down will now consist of selections of either 0 to 600 or 600 to 4000. This range links other calibration tasks to the applicable calibration data entry worksheet. Other calibration worksheets will import data from the linked calibration data entry worksheet.

 

Performing the Repeatability Check

  1. Start the task by clicking Start Calibration.
    • If the task has already begun then click Open Worksheet to view it. The "Balance Repeatability Check" screen will appear.

  2. Enter the data as required from checking the balance readings.

Performing the Single-Point Check

  1. If this is the first time entering a result, start the task by clicking Start Calibration.
    1. If the task has already began then click Open Worksheet to view it. The "Balance Single-Point Check" screen will appear.

  2. Click Add New Entry to create a new entry in the table.

  3. Select the Mass Type.
    1. User Defined: Will allow the user to enter the Check Mass No., Check Mass and Check Mass Uncertainty. 
    2. Calibrated: If calibrated masses exists in the equipment list in QESTLab then they will be visible in the frame labelled "Calibration Masses". The Check Mass No., Check Mass and Check Mass Uncertainty will be imported from the selected  calibration masses.
  4. Enter the calibration details as required. 
    Note: The "Standard Deviation from Last External Calibration" will import from the Calibration Data Entry calibration screen.

  5. When data entry for the day is complete, simply leave the screen.

When opening the Single-Point Check task for a second time, the Last Date Performed will be updated. This prevents the task from appearing as due until the next cycle, and changes the Due On date to the next cycle.

The Balance Single-Point Check document is not intended to be "finished" after each use, but rather at the end of each year when starting a new cycle. The document is set to complete by clicking the Finish Calibration button. After this, the task can be started again for a new cycle.


Performing the Limit of Performance Calculation

If either the repeatability or single-point checks fail, the user is prompted with a warning. This will inform the user that either a full calibration needs to be completed, or a new Limit of Performance calculated to determine the usefulness of the balance. It is left up to the user to decide which of these to perform. If the user decides a full calibration is in order, the equipment can be set to "Not In Service" and the full calibration task performed. Otherwise the user can perform the limit of performance calculation as follows:

  1. Start the task by clicking Start Calibration.
    1. If the task has already begun then click Open Worksheet to view it. The "Balance Limit of Performance" screen will appear.

  2. Select the Scale Range.

  3. Enter the data as required and the new limit will be calculated. 

Performing the Single-Point Check for Moving the Balance 

A screen is available for performing single-point checks when moving the balance. To use this feature:

  1. Create a new task for the check, called "Single-Point Check when Moving".
    1. Select the Balance Single-Point Check when Moving document in the worksheet drop-down.
    2. Set the schedule as a "Once Off" task.

  2. Start the task by clicking Start Calibration.
    1. If the task has already begun then click Open Worksheet to view it. The "Balance Single-Point Check when Moving" screen should appear.
  3. Fill out the details as required



Products described on these pages, including but not limited to QESTLab®, QESTNet, QESTField, Construction Hive, and associated products are Trademarks () of Spectra QEST Australia Pty Ltd and/or related companies.

The content of this page is confidential. Do not share, duplicate or distribute without permission.

© 2020 Spectra QEST® Australia Pty Ltd and/or related companies.  Terms of Use and Privacy Statement


Related content

Integrity | Curiosity | Empathy | Unity

The content of this page is confidential and for internal Spectra QEST use only. Do not share, duplicate or distribute without permission.