Accurate Technology 150 User manual

User’s Manual for:
ProScale Model 150 & 250
Systems using:
Firmware V2.1x and Higher
Firmware V2.2xC and Higher
Manual Revision H, 5-2006
ProScale
™
Model 150
Model 250
LCD Digital Displays

Accurate Technology ProScale Page 2 of 48
WARRANTY
Accurate Technology, Inc., warrants the ProScale Model 150 and Model 250
against defective parts and workmanship for 3 years commencing from the
date of original purchase. Upon notification of a defect, Accurate
Technology, Inc., shall have the option to repair or replace any defective part.
Such services shall be the customer's sole and exclusive remedy. Expenses
incidental to repair, maintenance, or replacement under warranty, including
those for labor and material, shall be borne by Accurate Technology, Inc.
(Including freight or transportation charges during the first 30 days).
Except as expressly provided in this warranty, Accurate Technology, Inc.,
does not make any warranties with respect to the product, either expressed
or implied, including implied warranties of merchantability or fitness for a
particular purpose, except as expressly provided in this agreement.
Accurate Technology, Inc., shall not be liable for any special, incidental, or
consequential damages or for loss, damage or expense directly or indirectly
arising from the customer's use of or inability to use the equipment either
separately or in combination with other equipment, or for personal injury or
loss or destruction of other property, or from any other cause.
To request repair work (either warranty qualified parts or not), contact
Accurate Technology, Inc. directly by phone, fax, or e-mail. A Returned
Merchandise Authorization (RMA) number is required before returning a
product for repair.
Accurate Technology, Inc.
+1 828.654.7920 800.233.0580 828.654.8824 (F)
www.proscale.com [e-mail]
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S
SA AF FE ET TY Y W WA AR RN NI IN NG G
Before installing ProScale on any machinery:
Turn off machine and disconnect power.
S
SA AF FE ET TY Y W WA AR RN NI IN NG G

ProScale M150, M250 with LCD Digital Displays Page 3 of 48
FCC NOTICE
This equipment has been tested and found to comply with the limits for a
class B digital device, pursuant to part 15 of the FCC Rules. These limits are
designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates, uses and can radiate
radio frequency energy and if not installed and used in accordance with the
instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular
installation. If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the equipment off
and on, the user is encouraged to correct the interference by one or more of
the following measures:
•Reorient or relocate the receiving antenna.
•Increase the separation between the equipment and the receiver.
•Connect the equipment to an outlet on a circuit different from that to
which the receiver is connected.
•Consult the dealer or an experienced radio/television technician for
help.
Operation with non-approved equipment is likely to result in interference to
radio and TV reception. The user is cautioned that changes and
modifications made to the equipment without the approval of the
manufacturer could void the user’s authority to operate this equipment.


Accurate Technology ProScale Page 4 of 48
Table of Contents
SECTION 1 GENERAL INFORMATION............................................... 6
I NTRODUCTION ....................................................................................... 6
W HAT T HIS M ANUAL I NCLUDES ................................................................. 6
P RODUCT S PECIFICATIONS ....................................................................... 7
P RO S CALE T ERMINOLOGY ....................................................................... 8
Scales .............................................................................................. 8
Absolute ........................................................................................ 8
Incremental.................................................................................... 9
Readheads ......................................................................................10
Absolute .......................................................................................10
Incremental...................................................................................10
D ISPLAYS .............................................................................................11
Measurement Compensation Option..................................................11
Surface Mount LCD Displays.............................................................12
Basic Display ................................................................................12
General Purpose, Battery ..............................................................12
General Purpose, 24VDC ..............................................................12
General Purpose, Wireless ............................................................12
Panel Mount LCD Displays................................................................13
Panel Mount, Basic, Battery...........................................................13
Panel Mount, General Purpose, Battery..........................................13
Panel Mount, Basic, 24VDC...........................................................13
Panel Mount, General Purpose, 24VDC..........................................14
Other Displays..................................................................................15
SECTION 2 MODEL 150 & MODEL 250 .............................................16
P RO S CALE M ODEL 150 ..........................................................................16
Scale & ReadHead Installation ..........................................................16
P RO S CALE M ODEL 250 ..........................................................................19
Scale & ReadHead Installation ..........................................................19
D ISPLAY I NSTALLATION ...........................................................................22
Surface Mount Display......................................................................22
Panel Mount Display.........................................................................22
SECTION 3 CALIBRATION/MAINTENANCE .....................................23
C ALIBRATION ........................................................................................23
C OMPENSATION C ALIBRATION ..................................................................24
M AINTENANCE .......................................................................................25
Changing the Batteries......................................................................26

ProScale M150, M250 with LCD Digital Displays Page 5 of 48
SECTION 4 DISPLAY OPERATION....................................................27
T HE LCD..............................................................................................27
P ROGRAMMING ......................................................................................27
Programming Parameters .................................................................28
Primary Key Functions......................................................................33
ON/OFF .......................................................................................33
MODE..........................................................................................33
+, 0, and – Keys............................................................................34
Auxiliary Keypad Functions ...............................................................34
ABS - INC.....................................................................................34
MONitor........................................................................................35
HOLD...........................................................................................35
SEND...........................................................................................36
F1 / F2..........................................................................................36
Display Functions .............................................................................37
Lock Mode....................................................................................37
Segment Offset Adjustment ...........................................................37
Offset Addition ..............................................................................37
Limit Mode....................................................................................38
Scaling .........................................................................................38
Compensation Mode .....................................................................38
Backlighting (24VDC Displays only)................................................38
Limit/Monitor Signal Output (24VDC Displays only) .........................38
24VDC Display Operation..............................................................39
Jumpers...........................................................................................40
Surface Mount Displays.................................................................40
Panel Mount Displays....................................................................41
Q UICK R EFERENCES ..............................................................................42
Display Feature Matrix......................................................................42
Circuit Board Jumper Summary.........................................................42
Programming Summary ....................................................................43
Key Press Function Summary ...........................................................44
SECTION 5 MISCELLANEOUS..........................................................45
F REQUENTLY A SKED Q UESTIONS .............................................................45
P RODUCT C OMMUNICATION .....................................................................45
SECTION 6 ACCESSORIES ..............................................................46
SECTION 7 SPARE PARTS...............................................................47

Accurate Technology ProScale Page 6 of 48
S ECTION 1 G ENERAL I NFORMATION
Introduction
ProScale™ digital measuring systems are affordable precision electronic
devices for making linear measurements with speed and accuracy. ProScale
consists of a S CALE , a R EAD H EAD (also called ENCODER ) and a digital
D ISPLAY . ProScale uses capacitive encoder technology, the same technology
used in digital calipers.
Because ProScale is a solid-state electronic device there's very little to wear
out. The ReadHead and Scale are designed to withstand shop dirt, dust, and
other airborne contaminants, and the controls are sealed with a protective
cover. With normal care, ProScale will last for years.
ProScale is ideal for most measuring requirements up to 6m (20ft.) where
high accuracy, >10 m, (approximately .0005”) is not needed, but affordable
repeatability, (better than a tape measure), or accuracy to 50 m (.002”) is
desired. Because ProScale shows the exact measurement on its Display, it
eliminates the guesswork involved in reading and interpreting tape measures,
scales & pointer, or shaft encoders. It is compatible for retrofitting, or as
original equipment, on most machinery or for any general purpose
measurement application where data is collected (SPC, RS232, RS485)
and/or digital accuracy and repeatability is desired.
What This Manual Includes
This manual includes information for ProScale Model 150
and Model 250 measurement systems with LCD Digital
Displays using:
•Firmware V2.1x and higher.
•Firmware V2.2xC and higher

ProScale M150, M250 with LCD Digital Displays Page 7 of 48
Product Specifications
Measuring Range*:
Model 150: 2 Standard Sizes:
0-250mm (10in) and 0-450mm (18in)
Model 250: 7 Standard Sizes:
0 to 300mm, 600mm, 1.3m, 2.4m, 3.0m, 3.6m, 6.0m
(0 to 12in, 24in, 52in, 96in, 120in, 144in, 240in)
Accuracy: + (.025 + .064 x L / 430) mm;
max error + 0.20mm @ 1.3 to 6m
+ (.001 + .0025 x L / 17) in;
max error + .008in @ 4 to 20 feet
(L = length of measurement in mm or inches)
Resolution Reduced: .1mm/.01cm/.01in;
Normal: .01mm/.001cm/.001in;
Increased: .01mm/.001cm/.0004in
Repeatability: .01mm or .001cm or .001in
Display Range: + 9999.99 mm; + 999.999 cm; + 999.999 in;
+ 399 63/64 in
Operating Temp: 0 to 50°C; 32 to 120°F
Temp Coef: 25ppm/°C; 13ppm/ °F
Max. Slew Rate: 400 mm/sec. (15 inches/sec.)
Accessories: See Section 6
Output Format: Mitutoyo Digimatic® SPC
ReadHead: 3m (10’), six-conductor cable terminated by RJ12
connector. (Maximum cable length 6m)
Dimensions: Available at www.proscale.com.
US Patents: 4420754, 4879508, 4878013, 4959615
Warranty: Three years from date of purchase.
All ProScale products are MADE IN USA
* MEASUREMENT range is approximately 100mm (4in) shorter than PHYSICAL
lengths.

Accurate Technology ProScale Page 8 of 48
ProScale Terminology
All ProScale M150 and M250 systems consist of a SCALE, a READHEAD,
(or encoder) and a DISPLAY (digital readout).
The SCALE consists of a series of conductive patterns bonded to an
aluminum extrusion. The Model 150 Scale is .765 inches (19mm) wide and
comes in standard lengths of 14.25 inches (362mm) and 22.25 inches
(565mm) to measure 10 inches (250mm) and 18 inches (450mm)
respectively.
The Model 250 Scale is 2.02 inches (51mm) wide and comes in several
standard lengths from 16 inches (406mm) to 244 inches (6.2m) to measure
from 12 inches (300mm) to 20 feet (6m) respectively.
NOTE: All ProScale Scales are approximately 4 inches (100mm) longer in
physical length than in their specified measuring capability.
The READHEAD, (sometimes called ENCODER ) contains a computer chip
which transmits and receives signals to and from the Scale using capacitive
coupling. The received signal is used by the ReadHead to calculate its
position to within 10 microns (10µm or .0004in). This position data is then
sent to the DISPLAY, where it can be displayed in millimeters, centimeters,
inches, or fractions and sent to an external data acquisition device via the
Display’s SPC output, or wirelessly via RF.
Multiple READHEADs (connected to individual DISPLAYs or data acquisition
units) may be used on the same SCALE simultaneously.
Scales
Absolute
Absolute, (often referred to as ABS) systems use a robust and sophisticated
method to measure position, resulting in a high immunity to electrical
interference and one that does not forget its position when power is removed.
An ABS system measures its actual position by reading a pattern which is
unique at any given location over a segment length. The maximum length of
a ProScale absolute segment is 430.08mm (16.933 in.). The segment must
then repeat.
Consider the illustration above to represent a ProScale approximately 50
inches long. There are three absolute segments joined together. Within

ProScale M150, M250 with LCD Digital Displays Page 9 of 48
Incremental Scale
each segment the system is absolute. However, crossing over a segment
joint now presents the ReadHead with information identical to what it read in
the previous segment. At this point the system must be able to recognize
that it has crossed a joint and therefore must add or subtract the value of 1
segment: 430mm. In fact, each time the ReadHead passes over a joint it
must keep track of how many segments it has passed, and in which direction.
This action is accomplished by the Display and is transparent to the operator.
What does all this mean? If the ReadHead remains on the same absolute
segment, it can have power removed, its position changed and power
restored without loss of position information. However, if power is removed
(ReadHead unplugged from Display or batteries removed from Display) and
the ReadHead passes over a segment joint, the transition will not be
recognized. When power is restored the system knows its absolute position
on the new segment, but does not know how many segments it has passed,
or in which direction. (Simply turning the Display off does NOT constitute
removing power. A small amount of power is still supplied to the ReadHead;
only the LCD is turned off.)
Displays provide the operator with a method to adjust the segment offset so
the system displays the correct reading at all times without loss of accuracy.
See Section 4 for additional information on Segment Offset Adjustment.
All Absolute (ABS) Scales have a “zigzag” pattern on a green laminate.
There may be a “SPLICE or JOINT” approximately every 430mm (17in.).
To shorten ProScale ABS Scales see:
http://www.proscale.com/other/absscalecut.htm
Incremental
Some older ProScale systems, such as the Model 100 and Model 200, as
well as other Accurate Technology products use Incremental technology. The
ReadHeads and Scales of different technologies are not compatible.
Incremental Scales have a repeating “bar” pattern on a colored laminate.
All ProScale Model 150 and Model 250 Systems Use Absolute (ABS) parts.
Absolute and Incremental Scales are not interchangeable.
See Section 7: S PARE P ARTS for Scale Part Number information.
Absolute (ABS) Scale

Accurate Technology ProScale Page 10 of 48
Readheads
Absolute
Absolute (ABS) style ReadHeads have “BLACK END OF SCALE” labels on
the housing cover, and the cable exits from the corner of the housing. Care
must be taken not to damage the brass “fingers” inside the ReadHead
housing. ABS style ReadHeads, used in all Model 150 and Model 250
systems, must only be used on ABS Scales and with a particular orientation.
Each ReadHead has an arrow on the label pointing in the direction of the
“BLACK END OF SCALE”.
Each ABS style Scale will have one end
painted black. This relationship is very
important, since the ReadHead may
work, but produce erratic results if
installed backwards. To insure proper
operation, be sure the arrow on the
ReadHead is pointing toward the
BLACK end of the Scale. The standard
ABS ReadHead has a round black (older
systems have flat gray) cable 10 ft. (3m)
long. For special cable lengths, contact
Accurate Technology, Inc. ABS ReadHeads will only work on ABS Scales.
Standard ABS ReadHead is supplied with a 3m (10ft) cable. Custom length
cables are available up to 6m (20ft).
Part #: 701-1500-120 (last 3 digits indicate cable length in inches)
Incremental
Older ProScale M100 and M200 Systems
use Incremental style ReadHeads. These
ReadHeads may not have labels on the
cover, the wire is black or gray and exits
from the center of the ReadHead housing.
Incremental ReadHeads will only work on
incremental Scales.
Standard Incremental ReadHead is supplied with a 300mm (12in) cable.
Part #: 701-1500-N12 (last 3 digits indicate cable length in inches)
All ProScale Model 150 and Model 250 Systems Use Absolute (ABS) parts.
Absolute and Incremental ReadHeads are not interchangeable.

ProScale M150, M250 with LCD Digital Displays Page 11 of 48
Displays
ProScale Model 150 and 250 measuring Systems can operate with any of
several different Displays (sometimes referred to as Digital Readouts). This
manual covers the operation of the General Purpose LCD (Liquid Crystal
Display) Displays. Other available Displays are mentioned in this section,
and other data acquisition accessories are mentioned in Section 6 of this
manual. For more information about the available Displays for ProScale
Model 150 and 250 Measuring Systems please visit:
http://www.proscale.com/displays/displays.htm
Measurement Compensation Option
This is Accuracy Enhancement software (firmware) available on General
Purpose Battery and 24VDC Surface Mount Displays and General Purpose
Battery and 24VDC Panel Mount Displays. This firmware option provides
increased accuracy of measurements by utilizing linear interpolation
calculations in the ProScale Display. The process incorporates an error
correction table that “maps” the physical scale measurements to a set of
known accuracy table entries. Use of this feature can enhance the
measuring accuracy of a ProScale measurement system.
The compensation system is designed to be simple for the user to recalibrate
in the field. Recalibration requires a set of measurement standards whose
accumulated length is approximately that of the ProScale measuring system
question. These measurement standards must be in multiples of a common
length. Examples would be 5”, 10”, 15”, 20”, etc. A 5”, 10” and numerous
20” standards would be adequate to accommodate most ProScale lengths.
The firmware accommodates a maximum of 32 correction table entries.
Using a 5” measurement standard multiple would yield a total compensation
range of 160” or 13.3 feet (4.064 m). Smaller standards equal higher
accuracy correction but less range. Longer standards equal longer range but
lower accuracy correction.
ProScale display units that support the compensation feature have a “C” at
the end of the firmware revision displayed on power-up or when ON/OFF key
is pressed.
See Section 3: C OMPENSATION C ALIBRATION for additional information.

Accurate Technology ProScale Page 12 of 48
Surface Mount LCD Displays
The Surface Mount LCD Displays are an ideal choice for applications where
flexibility and easy installation are important. They can be installed with
something as simple as Velcro™ or double sided tape, or by using the screw
locations inside of the back case or on the outside of the back case. Several
versions of this Display are available as described below.
Basic Display
This Display operates on 2 AA batteries. It is ideal
for machinery applications where more advanced
programming features are not desired or required.
This Display has most of the programming features
of the General Purpose Display but has no data or
signal output capability, or special function keys.
Part Number: 700-1600-220
General Purpose, Battery
This Display operates on 2 AA batteries. It includes
all the features of the B ASIC Display plus it has an
auxiliary keypad with 6 keys for switching between
ABSolute and INCremental measurements,
MONitoring position drift, SENDing SPC data,
HOLDing the reading, and F1/F2 special functions.
Part Number: 700-1600-200
General Purpose, 24VDC
This Display operates on 24VDC. It includes all
the features of the G ENERAL P URPOSE , B ATTERY
Display. It comes with a connector that allows
easy connections for supply voltage and output
connections for the Limit Alarm / Monitor Output
signal. This Display also has LCD Backlighting.
For use with ProScaleABS systems ONLY.
Part Number: 700-1600-205
General Purpose, Wireless
This Display operates on 2 AA 3.6V Lithium Ion
batteries. It includes all the features of the
G ENERAL P URPOSE , B ATTERY Display. It has a
built in RF transmitter that allows data to be sent
wirelessly to a ProScale-RF receiver (Part # 700-
1036-xxx) which has an RS232 output.
(See Section 4: J UMPERS for important battery
configuration information)
Part Number: 700-1600-250

ProScale M150, M250 with LCD Digital Displays Page 13 of 48
Panel Mount LCD Displays
The Panel Mount LCD Display for panel and enclosure mounting applications
is a perfect choice for manufacturers or OEMs that desire the “built in”
appearance for the digital measuring system. This Display comes in three
versions, all designed to fit a ¼ DIN (90mm x 90mm, 3.5in x 3.5in) panel
opening.
Panel Mount, Basic, Battery
This Display operates on 2 D batteries.
It is ideal for machinery applications
where more advanced programming
features are not desired or required.
This Display has most of the
programming features of the General
Purpose Display
Part Number: 700-1600-405
Panel Mount, General Purpose, Battery
This Display operates on 2 D batteries.
It includes all the features of the B ASIC
Display plus it has an auxiliary keypad
with 6 keys for switching between
ABSolute and INCremental
measurements, MONitoring position
drift, SENDing data out the SPC
connector, HOLDing the reading, and
F1 & F2 special function keys.
Part Number: 700-1600-400
Panel Mount, Basic, 24VDC
This Display operates on 24VDC. It is
ideal for machinery applications where
more advanced programming features
are not desired or required.
This Display has most of the
programming features of the General
Purpose Display and has LCD
Backlighting.
For use with ABS systems ONLY.
Part Number: 700-1600-305

Accurate Technology ProScale Page 14 of 48
Panel Mount, General Purpose, 24VDC
This Display includes all the features of
the B ASIC 24 VDC Display plus it has an
auxiliary keypad with 6 keys for switching
between ABSolute and INCremental
measurements, MONitoring position drift,
SENDing data out the SPC connector,
HOLDing the reading, and F1 & F2 special
function keys. It comes with a connector
that allows easy connections for supply
voltage and also serves as the output connection for the position Limit /
Monitoring output signal. This Display also includes LCD BackLighting.
For use with ABS systems ONLY.
Part Number: 700-1600-300
See D
ISPLAY F EATURE M ATRIX in this manual for additional information.
The preceding Displays are direct replacements for the following
Discontinued Displays:
Old Display Type Old Number Replacement
General Purpose 701-1600-001 700-1600-200
General Purpose Basic 701-1600-020 700-1600-220
Basic 701-1495-001 700-1600-220
Standard 701-1500-00x 700-1600-200
SPC 701-1505-00x 700-1600-200
Programmable 701-1115-00x 700-1600-200
Panel Mount, Battery 701-1570-001 700-1600-400
Panel Mount, 24VDC 701-1560-001 700-1600-300
Panel Mount, Battery 701-1525-00x 700-1600-400
Panel Mount, 24VDC 701-1550-00x 700-1600-300
Incremental 701-2000-002 700-1600-025
Incremental 701-1495-002 700-1600-025
(Where ‘x’ denotes any number from 0-4.)

ProScale M150, M250 with LCD Digital Displays Page 15 of 48
Other Displays
ProScale Model 150 and 250 systems can also be configured with any of the
following Displays. Operation of these Displays is covered in their own
respective manuals.
1/8 DIN LED Panel Mount
Readout: Inches, MM (no fractions)
Output: RS485 Output
Power: 24VDC
Part #: 700-1600-090
http://www.proscale.com/displays/led.htm
1/4 DIN Backlit LCD Panel Mount
Position Control Unit
Readout: Inches, MM (no fractions)
Output: Power Motor Relay Output
0-10V Analog Output
Features: Monitor Position
Custom Programming
Power: 24VDC
Part #: 700-1600-110
http://www.proscale.com/displays/pcu.htm
Dual Input Backlit LCD Panel Mount
Readout: Inches, MM Fractions
Output: 2 Independent Outputs
SPC & RS232
Features: 2 Independent Inputs
A+B, A-B, ArcTangent
Programmable outputs
Hold / Monitor Reading
Power: 24VDC
Part #: 700-1600-500
http://www.proscale.com/displays/dual.htm

Accurate Technology ProScale Page 16 of 48
S ECTION 2 M ODEL 150 & M ODEL 250
ProScale Model 150
ProScale Model 150 is a general purpose measuring system with standard
measuring ranges of 250mm (10”) or 450mm (18”).
Model 150 systems use Absolute (ABS) style Scales, Absolute (ABS) style
ReadHeads, and any of several available Displays. This manual covers the
operation of the General Purpose LCD Displays with Firmware (F/W) version
2.1 or higher.
Multiple ReadHeads connected to individual Displays or data acquisition
units may be used on the same Scale simultaneously.
Scale & ReadHead Installation
ProScale Model 150 is easy to install. By following the basics of good
installation, reliable, error-free operation can be expected. ProScale M150
can be used in many different measurement applications, and with numerous
types and brands of equipment. Therefore all installations will be a little
different and it is the responsibility of the user to choose the bolts, screws, or
other mounting hardware that guarantee proper installation for optimum
operation.
Note: If a custom kit was ordered which contains instructions for installing
this ProScale on a specific product, follow those instructions rather
than the installation and calibration instructions in this manual.
ProScale Model 150
-
10 shown with Surface
M
ount General Purpose LCD Display

ProScale M150, M250 with LCD Digital Displays Page 17 of 48
Connector Link
Guide Clip
1. Note the orientation of the ReadHead on the Scale. Be sure the arrow
on the ReadHead points towards the “BLACK END OF SCALE”. This
orientation is critical for proper operation. Be sure the mounting location
for the ReadHead and Scale will allow this orientation. Take care when
sliding the ReadHead onto the Scale so the brass “fingers” inside the
ReadHead do not get damaged. (A slight “wiggling” motion when
installing the ReadHead will simplify the process.)
2. Determine an appropriate mounting location. Most applications of the
Model 150 will have the ReadHead held stationary while the Scale is
passed through the ReadHead. The ProScale will also operate properly
if the ReadHead is moved along the Scale (see figures on next page).
3. If the ReadHead is to be mounted stationary, the
Scale should be attached to a moving part of the
measuring application or machine using the
Connector Link. Attach the ReadHead using three
screws or bolts. Attach one end of the connector link
to the Scale using the included 10-32 screw (or M5)
and the other end to the moving part. Check that the
Scale is properly aligned with the direction of motion
of the moving part. Be sure both connections are
secure or inaccurate/erratic readings could result.
(The connector link compensates for small
misalignments of the installation and acts as a shear
pin). Failure to use the connector link could void the warranty.
4. If your application is more suited to the Scale being
held stationary and the ReadHead moving, you should
use the Guide Clip to move the ReadHead along the
Scale (see figure on next page). The connector link is
not necessary in this configuration. Mount the Scale
using the included 10-32 screw (or M5). Be sure the
Scale is properly aligned as the ReadHead is moved
(the Guide Clip will compensate for slight misalignment
in one direction only). Adjust Scale alignment if
necessary.
For accurate measurements, the guide clip must be mounted
perpendicular to the direction of travel of the ReadHead. The guide clip
should exert some pressure over the full range of travel on the
ReadHead so the two move as a single unit. Failure to use the guide
clip could void the warranty.

Accurate Technology ProScale Page 18 of 48
5. The Display may be mounted in a location which allows for easy viewing
by the operator. The location of all parts should also safeguard the
cable from possible damage. ProScale wiring should be kept away from
electrical wiring and motors. Plug the ReadHead into the Display. See
Section 4: D ISPLAY O PERATION .
Note: If any other mounting method is used, observe the following:
•Do not drill through the green portion of the Scale at any point over
which the ReadHead will travel.
•Do not mount the Scale so the mounting hardware interferes with the
movement of the ReadHead.
Typical Model 150 Installations
G uide C lip
Sc ale
R ea d h ea d
M o vin g pa rt
Readhead stationary, Scale moves
Scale stationary, Readhead moves
Moving Part
Connector Link
Readhead
Scale

ProScale M150, M250 with LCD Digital Displays Page 19 of 48
ProScale Model 250
ProScale Model 250 is a general purpose measuring system with seven
standard measuring ranges from 0-300mm (12in.) up to 0-6m (20ft.).
Model 250 systems use Absolute (ABS) style Scales, Absolute (ABS) style
ReadHeads, and any of several available Displays. This manual covers the
operation of the General Purpose LCD Displays with Firmware (F/W) version
2.1 or higher.
Multiple ReadHeads connected to individual Displays or data acquisition
units may be used on the same Scale simultaneously.
Scale & ReadHead Installation
ProScale Model 250 is easy to install. By following the basics of good
installation, reliable, error-free operation is assured. ProScale Model 250 can
be used in many different measurement applications, and with numerous
types and brands of equipment. Therefore all installations will be a little
different and it is the responsibility of the user to choose the bolts, screws, or
other mounting hardware that guarantee proper installation for optimum
operation.
Note: If a custom kit was ordered which contains instructions for installing
this ProScale on a specific product, follow those instructions rather
than the installation and calibration instructions in this manual.
ProScale Model
250
shown with
Panel
M
ount General Purpose LCD Display

Accurate Technology ProScale Page 20 of 48
Guide Clip
1. Note the orientation of the ReadHead on the Scale. Be sure the arrow
on the ReadHead points towards the “BLACK END OF SCALE”. This
orientation is critical for proper operation. Be sure the mounting location
for the ReadHead and Scale will allow this orientation. Take care when
sliding the ReadHead onto the Scale so the brass “fingers” inside the
ReadHead do not get damaged. (A slight “wiggling” motion when
installing the ReadHead will simplify the process.)
2. Determine an appropriate mounting location for the system.
Recommended Model 250 applications usually have the Scale held
stationary while the ReadHead is moved along the Scale. However, the
ProScale will read correctly if the ReadHead is moved along the Scale or
if the Scale is moved through the ReadHead.
3. When installing the Model 250, you should use the
Guide Clip to move the ReadHead along the Scale
(see figures on next page). Mount the Scale using the
included 8-32 screw (or M4) Be sure the screw
heads do not protrude above the surface of the
extrusion. Check that the Scale is properly aligned as
the ReadHead is moved over its length (the Guide
Clip will compensate for slight misalignment in one
direction). Adjust Scale alignment if necessary. For
accurate measurements, the guide clip must be
mounted perpendicular to the direction of travel of the ReadHead. The
guide clip should exert some pressure over the full range of travel on the
ReadHead so the two move as a single unit. Failure to use the guide clip
could void the warranty.
4. The Display may be mounted in a location which allows for easy viewing
by the operator. The location of all parts should also safeguard the cable
from possible damage. ProScale wiring should be kept away from
electrical wiring and motors. Plug the ReadHead into the Display. See
Section 4: D ISPLAY O PERATION
Note: If any other mounting method is used, observe the following:
•Do not drill through the green portion of the Scale at any point over
which the ReadHead will travel.
•Do not mount the Scale so the mounting hardware interferes with the
movement of the ReadHead.