Calibration & Product Accuracy Certifications

In measurement instruments and precision tools, ACCURACY and RELIABILITY are important aspects to users. Decisions taken following inaccurate readings from instruments would result in unintended consequences. Digi-Pas® Precision Digital Levels and Inclinometers are compensated and calibrated for non-linearity and wide operating temperature variation utilizing company's proprietary advanced manufacturing patented processes. To enhance transparency, ensure impartiality and competence, Digi-Pas® product's accuracy performance has been externally verified by numerous accredited world-leading certification bodies employing ultra-high precision nanotech turning machines and angular Interferometers.

Calibration Certificates on Digi-Pas® product conformity assessments are obtained from independent accredited third parties and world-leading National Metrology Laboratories under Bureau International des Poids et Mesures (CIPM MRA). Digi-Pas® products are tested by TÜV SÜD, SGS to comply with CE, FCC, RoHS, and ACCURACY performance to specification has been verified and periodically re-validated by accredited Calibration & Test Laboratories in USA, Japan, UK and Germany traceable to NIST, JIS, UKAS & DIN under the International Laboratory Accreditation Cooperation (ILAC) and American Association for Laboratory Accreditation (A2LA), ensuring the acceptance of conformity assessments all over the world.

Production equipment and angular test instruments are periodically calibrated to our research laboratory angular standards, which in turn laterally compared against external 3rd parties independent certification standards in U.S., Japan, Germany and UK (see below certificates). Each batch of production test data including calibration documents are maintained in accordance to ISO9001 procedures, which kept available upon request by the related parties and authority. Only those high-precision models are each accompanied with hard-copied factory QA calibration certificate. Customers whom wish to have each product purchased accompanied with a hard-copied 3rd party certificate of any product model, please request our sales support for a quote.

The following samples of calibration certificate provide users with options to choose competent 3rd party Calibration Service Providers near your geographical region. These Service Providers have specialized precision angular test equipment and expertise which are capable of conforming to ISO/IEC 17025:2005 standard to test unique features of our products, particularly (i) 2-axis simutaneous angles measurements, (ii) very wide measurement range, and (iii) ultra-high precision. Digi-Pas® instrument's quality system ensure products manufactured conform to specification. Latest factory’s calibration certificates and/or external certifications can be obtained upon request by filling the form on "Contact Us".

Calibration Certificates

Description Country
USA UK Japan Singapore Germany
DWL80E Calibration Certificate      
DWL80Pro Calibration Certificate        
DWL130 Calibration Certificate      
DWL200 Calibration Certificate        
DWL280 Calibration Certificate    
DWL280Pro Calibration Certificate    
DWL600 Calibration Certificate  
DWL680Pro Calibration Certificate  
DWL1000XY Calibration Certificate      
DWL2000XY Calibration Certificate  
DWL3000XY Calibration Certificate
Boeing Transcat Micron JQA NMC Trescal
DWL3500XY Calibration Certificate  
A.A Jansson   JQA NMC Trescal
DWL5000XY Calibration Certificate  
DWL8500XY Calibration Certificate    
A.A Jansson   JQA NMC

Advantages of using Digi-Pas® 2-Axis precision digital inclinometer over conventional single-axis levelling instruments:

1. Traditional spirit 'bubble' level, pendulum-based or servo-driven digital levels and inclinometers were often constrained with (i) single axis, (ii) narrow angle measurement range, (iii) large footprint/size, (iv) inability to withstand high shock/impact and (v) mechanical moving parts that degrade quickly due to wear-and-tear. Single-axis inclinometer is also susceptible to cross-axis error particularly when measuring at larger angles and at higher precision. However, precision levelling, angle measurement, alignment and surface flatness profiling tasks essentially involve 2-dimensional plane rather than two independent orthogonal single-axis lines. Digi-Pas® 2-Axis precision inclinometer utilizing advanced semiconductor MEMS technology consisting NO-moving part, provides simultaneous 2-axis and wide angle measuring range capabilities unmatched by those traditional single-axis 'bubble' levels, pendulum or servo-based electronic inclinometers.

Digi-Pas® 2-Axis Machinist Digital Level on 2D (X-Y plane) of a 2-axis Sine Table
Digi-Pas® 2-Axis Machinist Digital Level on 2D (X-Y plane) of a 2-axis Sine Table

2. Digi-Pas® 2-axis MEMS technology enables simultaneous 2D (X-Y plane) leveling and angles measurement (i.e. pitch & roll), completely eliminates tedious trial-and-error (i.e. going back-and-forth taking reading one-axis at a time) experienced when using single-axis levels to align precision machines/objects. No costly need for owning 2 units of single-axis digital levels to do the same task as one unit Digi-Pas® dual-axis. i.e. effective & time saving. The repetitive yet monotonous trial-and-error activity of using single-axis levels is also time-consuming, non-productive and promote boredom that often succumb engineers to resort for compromising works.

3. Digi-Pas® 2-axis MEMS driven inclinometers are compensated and calibrated for non-linearity and wide operating temperature variation utilizing company's proprietary advanced manufacturing patented processes. Angular accuracy and stability performance over a very wide measurement range are externally verified by numerous accredited 3rd party independent certification bodies traceable to NIST, UKAS, DIN & JIS. i.e. accredited & reliable.

angular linearity angular deviation vs. temperature
Compensating and calibrating Digi-Pas® 2-Axis Machinist Digital Level

4. Digital Bull’s Eye with numerical/graphical data and a built-in VibroMeterenable machine installer to track/guide alignment in real-time and instantly verify positional stability of the levelled/aligned machine by comparing machine's status profiles before and after setting up. Dual axis smart Bull's eye also prevents parallax error that is prone to experience when viewing the 'bubble' of a traditional spirit level, i.e.accountability & quality works.

5. Wireless/USB connectivity to PC/mobile device enables field engineers to perform with ‘one-man-operation’ when conducting levelling and machine alignment tasks, i.e. speedy & cost saving.
One-man-operation can be performed when levelling machine using Digi-Pas® 2-Axis precision Digital Level via wireless Bluetooth connectivity
‘One-man-operation’ when levelling machine using Digi-Pas® 2-Axis precision Digital Level via wireless Bluetooth connectivity

6. Utilizing Digi-Pas® 2-axis inclinometer translates into speedy machine installation and productive maintenance works with professional quality that maximizes precision machine performance. Thus, leads to improved user's product quality (e.g. accuracy & yield) and higher customer satisfaction.

7. Digi-Pas® 2-axis digital inclinometer provides a comprehensive solution for precision levelling and angular measurement, and serves as a superior alternative that seeks to replace the use of outdated spirit levels and limited angle-measuring range of conventional single-axis digital levels.

8. Because of its 2-axis, wide angular measuring range and vibrometer functions, Digi-Pas®inclinometer is more than just a leveling tool. It is an instrument that provides a comprehensive solution for precision machine leveling, tilted-plane angle measuring, machine structural stability diagnostic and alignment needs.

9. Digi-Pas® DWL5000XY tilt-sensor module survived over 3,000g to 6,000g Shock/Impact Test in both X&Y directions thus makes it possible to be integrated in equipment/structures for high shock/impact applications, particularly in hostile environments inoperable by conventional pendulum or servo-driven tilt sensors. There is no moving parts inside Digi-Pas Sensor Module.

©2017 Digipas Technologies Inc. All Rights Reserved.

Digi-Pas® Precision Digital Level Accuracy and Reliability

Three-Point Contact Base of Digi-Pas® 2-axis Precision Inclinometer

  1. Limitations of conventional rectangular contact base levelling instrument

    The contact base surface finish quality of a typical conventional leveling instrument or inclinometer is one of the critical determinants of accuracy performance and common rectangular-shape flat surface often suffer from geometrical deviation resulting from:

    • Waviness and unevenness
    • Irregularities due to distorted or worn surface
    • Dust and dirt trapped or surface roughness

    Figure 1 illustrates three typical poor surface finishes of conventional rectangular surface four-point contact base. The unstable surface-to-surface contact causes 'rocking' which results in measurement inaccuracy derived from inconsistent readings. A common practice to improve the outcome under such constraint is by taking more samples to obtain an averaged reading. However, this time-consuming and repetitive activity often promotes boredom that succumb engineers to resort for compromising works, especially when the instrument is located at some distance.

    Figure 1 Poor surface finishes of typical levelling instrument contact base and implications
    Figure 1: Poor surface finishes of typical levelling instrument contact base and implications

    Although high quality surface requires both flatness and smoothness, it is difficult and expensive to control in machining of metal alloy surface particularly when involving relatively large area. Increasing the flatness and smoothness of a few microns would usually increase exponentially on its manufacturing costs. This often results in a trade-off between the manufacturing costs of the instrument and thus compromises its accuracy performance.

    In addition, the rectangular contact base surface of a conventional leveling instrument is also susceptible to target measuring surface unevenness, which is another factor affecting levelling and measurement accuracy. Figure 2 illustrates issues associated when a rectangular contact base of a traditional single-axis spirit level is placed on a typical machined surface having low frequency, long wavelength flatness variation. It is clearly shown that full and stable surface-to-surface contact could not be achieved between the instrument base and the measuring surface. The contact may cause rocking that results in measurement errors, hence affects the accuracy and reliability of the leveling outcome. E.g. a 3µm of surface unevenness along the length of a typical 20µm/m resolution spirit machinist level of 130mm would result in 0.001° error

    Figure 2: Conventional single-axis contact base on a two-dimensional uneven plane
    Figure 2: Conventional single-axis contact base on a two-dimensional uneven plane
  2. Digi-Pas® concave contact base versus 'perfectly flat' contact base structures

    Often, dents are easily generated on smooth metal base area of an instrument resulting from rough handling. A protruding dent formed at any location near the middle of a 'perfectly flat' metal base simply causes rocking which results in measurement error or inaccuracy. To minimize these errors, Digi-Pas® instrument metal surface base has been deliberately designed and machined to form a concave 4-points contact base specifically target to prevent rocking caused by small protruding dents or foreign particles formed at the center of device’s base. Figure 3 illustrates the inferiority of a 'perfectly flat' base of conventional instruments against the improved design of Digi-Pas® concaved 4-point base when small dents/particles exist at the center of device’s base. It is obvious that small dents or particles exist near the middle of the base shall not affect stability of Digi-Pas® instrument as it is supported by both ends having precisely machined stable contacts to the targeted measurement surface.

    Figure 3. Side view of perfectly flat contact base versus Digi-Pas® concave 4-point base
    Figure 3. Side view of perfectly flat contact base versus Digi-Pas® concave 4-point base

    On the other hand, dents formed at the both ends of the instrument may not necessarily cause significant rocking. When dents happen at these both ends, an offset value/reading caused by these dents can be easily removed using Digi-Pas® calibration or Absolute Level feature (see “Accuracy Performance”). In contrast, a protruding dent formed at the middle of the device’s base destabilizes the device with severe rocking during measurement which cannot be resolved by using calibration or Absolute Level feature. This phenomenon does not only affect the instrument's initial offset value, it also affects the repeatability of measurement reading.

    Thus, the contact surface approaching the base center of instrument is deliberately being designed with a concave profile to minimize the above issue, providing improved stability of measurement readings as well as enhances accuracy of the instrument.

  3. Pioneering the application of 3-point contact base in 2-axis precision levelling instrument

    In view of the constraints inherent in conventional contact base measuring instrument described in the foregoing, Digi-Pas® pioneered and patented the utility of 3-point contact base for its 2-axis precision angular and surface flatness measurement instruments. The triangular shape of 3-point contact base seeks to address the shortcomings associated with conventional rectangular contact base.

    Figure 4: Stable 3-point-to-surface contact between Digi-Pas® inclinometer and flat surface object
    Figure 4: Stable 3-point-to-surface contact between Digi-Pas® inclinometer and flat surface object
    Figure 5: Stable 3-point-to-surface contact between inclinometer and uneven surface
    Figure 5: Stable 3-point-to-surface contact between inclinometer and uneven surface

    When a 3-point contact base leveling instrument is placed on either flat or uneven surface object (e.g. typically machined metal surface) as shown in figure 4 and 5 respectively, the three-point frame serves as a triangle-plane platform for supporting the weight and maintaining the stability of the instrument. It provides maximum stability and strength against downward forces and horizontal forces as well as movements about horizontal axes. With the sturdy three-point stand, a most stable 3-point-to-surface contact can be established without rocking and thus achieving consistent leveling readings of the two-dimensional measuring surface. Any angular deviations on the surface area is detected by Digi-Pas® 2-axis inclinometer as sensitive contact points touch on a particular section of uneven surface area.

  4. Advantages of Digi-Pas® 3-point contact base levelling instrument

    In 2009, Digi-Pas® pioneered and patented the utility of 3-points contact base to its world-first 2-axis precision digital level series that effectively prevent any surface dimensional deviation caused by unevenness of its own instrument’s metal surface contact base. Figure 6 illustrates the 3-point contact base screws made of harden steel and titanium materials that offers great stability and prevent it from ‘rocking’ when placed on either flat or uneven smooth surface for 2D levelling and planar angular measurement.

    Figure 6: Digi-Pas<sup>®</sup> patented 2-Axis Precision inclinometer utilizing 3-Point Contact Base
    Figure 6: Digi-Pas® patented 2-Axis Precision inclinometer utilizing 3-Point Contact Base

    Maintaining the 3-points contact is easy, speedy and cost effective simply by replacing the harden/titanium screws whenever they wear off, saving significant amount of time and cost as compared to maintain the instrument’s contact base surface finish through standard machining. Device accuracy performance can also be re-calibrated by performing User Self-Calibration or “Absolute Level” setting at ease. Please refer to user manual for detail instructions.

    For using Digi-Pas® 2-axis inclinometer to level an object having a very rough top surface, the 3-point harden/titanium screws can be temporarily removed and use the flat base surface to naturally average the rough surface. Absolute Level Setting is required to be performed immediately after changing the base to ensure the instrument maintains its reference accuracy. However, in high precision leveling, angular measurement and surface profiling tasks usually involve high quality flatness and smooth surfaces such as granite and metal alloy machined surfaces. Hence, 3-point contact base is still a better choice.

©2017 DIGIPAS TECHNOLOGIES INC. All Rights Reserved