Glossary

ABC Scale Cut

To cut a ProScale Model 150 or Model 250 absolute style scale to length:

  1. Identify the end of the scale that is painted black - DO NOT CUT THIS END OFF!
  2. Mark the scale where it will be cut.
  3. Use parallel clamps or vice-grips to clamp the embedded stainless steel wires in place on the extrusion side(s).*
  4. Cut the extrusion to length. Cut into the side with the green circuit board first.
  5. Chamfer the cut end of the extrusion to match the original. This is most easily accomplished using a belt sander.
  6. Deburr the aluminum extrusion.
  7. Test the shortened scale by carefully sliding an Encoder on it. There should not be any binding.
  8. When possible, the end of the digital scale that is painted black should be kept and used closest to the desired zero position.

*Some scales manufactured after February 2008 may not have the stainless steel wires and this step can be skipped.

Absolute Measurement

An absolute measurement is the distance from some fixed position. On a table saw, this is typically the distance from the right edge of table saw blade. For the best accuracy, this is the distance from the right edge of the running blade - accounting for any variance of blade flatness, or bearing run-out. The absolute distance can be set to zero, or to any other offset, quickly and easily using the readout keypad. The absolute distance IS retained when the readout is turned off or switched into INCremental measuring mode.

Absolute Technology

Our Absolute encoder technology (ABS) has been in production since 1997. Absolute Technology measures the actual sensor position by reading a pattern which is unique at any given location over its length (approximately 17 inches). This results in a measuring system with a high immunity to loss of position due to motor electrical noise, power transients, or magnetic fields.

With absolute encoder technology, there is no position loss when the digital readout is turned off, or when power is interrupted.

ABS technology is still used in many of our products including the Model 150 and Model 250 ProScale systems and products. It is especially appropriate for environments with high voltage wiring, dust collection systems, and where a zero position cannot be quickly re-established.

Components of an Absolute (Model 150/250) measuring system:

ABS Scale (green & black pattern):

The aluminum extrusion for the Absolute digital scale is available in several different sizes:

  • 0.75" wide x 0.25" thick is Model 150 or 150-X
  • 2.02" wide x 0.75" thick is Model 250
  • 0.75" wide x 0.75" thick is Model 250-S

ABS Encoder:

  • Note the wire exits from the corner on one end of the housing. (Older or custom encoders may have a flat gray cable)
  • Until May, 2011 the housing is gray. After May 2011 the housing is Blue or black.
  • The base is black. (Pre 2012 models may have a gray base).
  • Newer models (since 2004) have labels that show the part number and serial number.
  • A "C" or "V" in the part number indicates a coiled cable.
  • An "H" in the part number indicates an encoder with a higher slew rate.
  • A "G" indicated an encoder used in a system that is operated with 12-24VDC.
  • An "S" indicates use with a Model 580 System.
  • Standard cable lengths are available up to 120 inches.
  • Custom cables available up to 360 inches. (Consider an RF transmitter for longer ranges)

Accuracy

The accuracy of a measurement system is the degree of closeness of measurements to its actual (or true) value.

"Accuracy and precision," Wikipedia, The Free Encyclopedia

Abbé Error

Abbe error is a condition that may not be visible to the human eye, but will affect linear measurements. Be sure to take precautions when installing ProScale in order to eliminate the possibility for Abbe error.

Abbe Error

Abbe error refers to a linear error caused by the combination of an angular error and a dimensional offset between the sample and the measuring system. It is important to understand that the information the encoder is providing is only the position of the Encoder on the scale. To illustrate this, see the figure, which shows a linear measuring device. (The apparent distortion in the measuring device is intentional - for this example - to show the measuring device with a curvature in its mounting.)

Suppose the curvature in the figure is sufficient to produce an angle of 40 arc-seconds. If the measuring device moves 10 inches, the probe will be found to have moved 10.0039 inches, resulting in an error of +0.0039 inches. Abbe error could be lessened by moving the measuring system closer to the sample. This effectively solves one half of the Abbe error problem (offset) and leaves only the angular mounting problem to be solved. Angular error can best be countered through proper design and placement of the linear scale. Sources of angular error include:

  1. Mounting the linear scale to an imperfectly flat surface.
  2. Mounting the linear scale to an imperfectly straight surface.
  3. Curvature of ways (or linear bearings) used to measure the sample.
  4. Contaminants between the probe and item being measured.
  5. Friction in any part(s) of the measuring device.

Capacitive Incremental Technology

Capacitive Incremental Technology

Our Capacitive Incremental measuring technology was used 1989 to 2009. Incremental technology measures the distance it has traveled relative to a starting point. As long as the signal is not reset or interrupted (by removal of batteries, electrical motor EMI, power transients, magnetic fields, static, etc.), the position information is not lost. Incremental technology was used in all of the measuring systems we manufactured until 1997. We began to phase out this technology in favor or more advanced Inductive Technology in 2007, and production was ended in 2009.

Products using this technology are no longer manufactured.

Fractions

Inches

Choose 16ths, 32nds, or 64ths. The digital readout automatically reduces fractional readouts to 4ths, 8ths, etc, in each mode. Additionally, bars appear in the upper right corner to show extra 64ths when in 16ths or 32nds mode. For example, when set to 16ths mode at 19/64", the digital readout will show 1/4" and three bars appear in the upper right corner, each indicating an additional 1/64" distance. In 32nds mode, the readout will show 9/32" and one bar appears in the upper right corner. In 64ths mode, the readout will show 19/64. This allows you to continue using the units you're familiar with, without making mistakes. It also speeds up cutting parts 'heavy' or 'long' when intended. NOTE: Fractions only appear when a particular dimension is reached. For example, you must actually reach 0.500 for the readout to show 1/2" in fractions mode. This prevents cutting parts too small -- especially important in work where parts stack or build together.

Inches

Inches

Choose either hundredths or thousandths of an inch by setting a switch inside the digital readout. The reading increments by 1 unit in either mode. For example, when set to thousandths mode, moving away from the blade will display 0.001, 0.002, 0.003, 0.004, 0.005, etc.

There is no position loss when the digital readout is turned off, or when power is interrupted.

 

Inductive Scale Cutting:

or

To cut your inductive style (M180/190, 280/290, 380/390, 580/590) scale to length, follow these simple steps:

  • Mark the scale where it will be cut. It can be anywhere!
  • Cut the extrusion to length. Cut into the side with the blue or black circuit board side first.
  • Deburr the aluminum extrusion.
  • Test the shortened scale by sliding a Encoder on it. There should not be any binding.

Inductive Series I Technology

Inductive Series I Technology

Our Inductive Series I Incremental measuring technology was in production since the 2007-2013. Inductive measuring technology measures the distance it has traveled relative to a starting point. It is however a much more robust technology than the Capacitive Incremental technology we used previous to 2007. Its signal is more immune to electrical motor EMI, power transients, magnetic fields, static, so the position information is not lost as easily as the older technology. Inductive Series I production ended in June 2013.

Products using this technology are no longer manufactured.

 

Inductive Series II Technology

Inductive Series II Technology

Our Inductive Series II Incremental measuring technology began production in June 2013. This technology, and the systems manufactured using it, are direct (mechanical) replacements for earlier Series I systems. Series II is more robust technology than Series I. Its signal is more immune to power transients, magnetic fields, and ESD. Plus, the slew (movement rate) is greatly increased. Series II technology is used in ProScale Models 190, 290, 390 and 590 as well as many of the turn-key measuring systems we manufacture incorporating these models.

The aluminum extrusion for the Series II SCALE is available in several different sizes:

  • 0.75" wide x 0.25" thick is Model 190
  • 2.02" wide x 0.75" thick is Model 290
  • 0.75" wide x 0.75" thick is Model 390
  • 2.99" wide x 0.61" thick is Model 590

Inductive Encoder

Top View Bottom View
  • Note the wire exits from the corner on one end of the housing.
  • The housing is black with a black base.
  • A label shows the part number and serial number.
  • Stock cable lengths available up to 120 inches.
  • Custom cables available up to 360 inches. (An RF transmitter is available for longer ranges.)

Incremental Measurement

An incremental measurement is the distance from a current (absolute) position. On a table saw, this could be the distance between dados or grooves. It could also be the distance from the left edge of the saw blade. The incremental distance can be set to zero, or to any other offset, quickly and easily using the readout keypad. Changing between Absolute and Incremental modes is easily done by pressing a single key. The incremental distance is retained when the readouts power is off.

Millimeters

Inches

Choose either tenths or hundredths of a millimeter by setting a switch inside the digital readout. The reading increments by 1 unit in either mode. For example, when set to hundredths mode, moving away from the blade will display 0.01, 0.02, 0.03, 0.04, 0.05, etc.

Repeatability

The precision of a measurement system, also called reproducibility or repeatability, is the degree to which repeated measurements under unchanged conditions show the same result.

"Accuracy and precision," Wikipedia, The Free Encyclopedia

RoHS Compliance

The RoHS directive aims to restrict certain dangerous substances used in electronic equipment. Any RoHS compliant component is tested for the presence of Lead (Pb). There must be no more than 0.1%. And, any RoHS compliant component must have 100 ppm or less of mercury.

SPC

Statistical Process Control is a tool that businesses and industries use to achieve quality in their products and/or services. By monitoring the accuracy, or in-tolerance percentage of manufactured products, and collecting current measurement data from measuring devices, a company can adjust their processes and machines to produce better products, faster. Most of our measuring products may be integrated into a company's SPC program by use of serial connection to a computer or printer.

This serial connection uses the format called Mitutoyo Digimatic® for the transmission of measured values or positions. Our encoders carry this signal to our digital readouts. Many of our digital readouts also have a 10-pin output connector which can be used to transmit the currently displayed reading. These signals may be gathered using Gageway or ProMux, or transmitted wirelessly using our ProRF products.

Learn more about Digimatic and data transfers using ProScale products.