Microplan ARCHIMEDE HR User manual
LARGE DIAMETER MEASURING INSTRUMENT
USER MANUAL
HR MODEL
“ARCHIMEDE HR” PART LIST
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81 Left arm in titanium
2 Right arm in titanium
3 Control Panel
4 Left support wheel
5 Right support wheel
6 Central support wheel
7 Lateral mechanical stop
8 Locking knob of central mechanical stop
9 Central mechanical stop
10 Locking knob of central mechanical stop
11 Left handle
12 Right handle
13 LCD Display
14 ON/OFF button
15 Bicolor led
16 Mini-USB input
17 “Save/Enter” button
18 MENU button
19 / MINIMUM button
20 / DISPLAY ROTATION
21 “Save/Enter” button
www.microplan-group.com
8
“ARCHIMEDE HR” PART LIST
1
7 4
10
18
19
5
2
11
9
12
6
3
13
7
14
20
21
15
16
17
81 Left arm in titanium
2 Right arm in titanium
3 Control Panel
4 Left support wheel
5 Right support wheel
6 Central support wheel
7 Lateral mechanical stop
8 Locking knob of central mechanical stop
9 Central mechanical stop
10 Locking knob of central mechanical stop
11 Left handle
12 Right handle
13 LCD Display
14 ON/OFF button
15 Bicolor led
16 Mini-USB input
17 “Save/Enter” button
18 MENU button
19 / MINIMUM button
20 / DISPLAY ROTATION
21 “Save/Enter” button
www.microplan-group.com
8
2019©Microplan®
ARCHIMEDE_HR_en.indd
Release: 19/03
ARCHIMEDE
Components and accessoires
ARCHIMEDE
Large diameters measuring instrument
Battery charger
USB key with «ARCHIMEDE» Soware
USB cable for battery charging and
PC connection
Manual
5
POWER
Archimede has an independent power supply with rechargeable batteries. The
batteries level is readable in the LCD display, the status indication is shown with
a small icon on the display:
Full charge
half charge
Low battery (auto-o)
In case of low battery Archimede automatically shuts o to prevent malfunctions
and inaccurate readings. In this case, it is necessary to leave the instrument
connected to the electrical power at least 30 minutes in order to reach the
minimum charge for a proper switching on.
With battery fully charged Archimede can work up to 8 hours of continuous duty.
Please use the instrument while connected to the battery charger only if extremely
urgent, in order not to have the power charge to influence the measurement
6
BATTERY
CHARGING
The instrument is supplied with USB Travel Adapter battery charger. You are
not allowed to use other chargers than the one provided, in order to avoid any
damage to the batteries and the electronic devices inside the instrument.
Connect the supplied battery charger to the USB plug on the Archimede arm and
let it charge for about 6 hours. As an alternative to the power supply, the device
can also be charged by connecting it to a PC USB port.
The bicolor LED, located on the main panel of the instrument shows two states
with the level of charge of the instrument:
Red led = battery charging
Green led = battery fully charged
7
THE MEASURING PRINCIPLE
OF THE ARCHIMEDE HR
The Archimede is a measuring instrument which detects a circumference passing
through the three points of tangency (ABC) between the cylinder to be measured and
the instrument support points.
This type of measurement oers advantages in terms of:
1 • Possibility to measures outside diameters from 500 to 6000 mm with a
single instrument and with a single person,
2 • Possibility to perform measurements of internal diameters from 1000
to 6000 mm with a single instrument and with a single person,
3 • Possibility to perform up to 12 measurements on the same circumference and
consequently obtain the values of the average diameter.
8
IS THE ARCHIMEDE HR SUITABLE
TO MEASURE ALL KINDS OF LARGE DIAMETERS?
Archimede HR is a device that due to its given flexibility, can be used in many production
fields. Its measurement principle allows to obtain the stated accuracy when measuring
cylindrical parts that do not have irregular shapes, such as those machined. The uncer-
tainty in the diameter measurement is directly influenced by the shape of the cylinder.
This means that, in order to achieve with Archimede an accurate measurement of a
cylindrical piece with a 1000 mm diameter, this must have a reduced circularity error.
Otherwise it becomes necessary to perform several measurements on the circumference
and detect the value of the average diameter.
DIAMETER ARCHIMEDE HR
500 ± 0.018 mm
1000 ± 0.043 mm
1500 ± 0.085 mm
2000 ± 0.143 mm
2500 ± 0.218 mm
3000 ± 0.310 mm
4000 ± 0.543 mm
5000 ± 0.843 mm
6000 ± 1.21 mm
Tab.1 Archimede Uncertainty
However, it is possible to measure an irregular cylinder repeating the measurement
on dierent arcs of the same cylinder, to obtain the value of the average diameter.
In any case, the max accuracy of measurement for Archimede is shown in Tab.1
9
IN CASE OF ELLIPTICAL CYLINDERS IS IT POSSIBLE THE MEA-
SUREMENT WITH ARCHIMEDE HR?
If the cylinder to be measured has a form error, Archimede will provide the value of the
diameter of a circumference passing through the three contact points on the cylinder
that is being measured. This could have a center not corresponding to the one of the
workpiece, but this does not mean that Archimede is returning a wrong measurement.
It is to be kept in mind that in case of elliptical cylinders (ellipses) the calculation
performed by Archimede for each measurement is related to the best fit circumference
passing by the instrument support points. This means that it is not possible to perform
a single measurement, but it is required to detect a series of measures (eg. 0°, 90°, 180°,
270°), from which obtain a value of Average Diameter.
In case it is necessary to measure a large size tube, if the shape error is high, it will not be
possible to determine a value of an average diameter of the piece, because the circularity
error of the cylinder makes it more similar to an ellipse or a polygon, that by definition
do not have geometric diameter.
10
HOW WE PROCEED TO DETERMINE THE VALUE OF
THE AVERAGE DIAMETER WITH ARCHIMEDE HR?
When you want to minimize the problem of circularity error, it’s useful to divide the
cylinder circumference in up to 12 arcs of 30°. On each arc is then taken the diameter
measurement, to obtain the value of the Average Diameter.
In case of measurement of a very irregular or deformed cylinder, the value of the average
diameter calculated by Archimede may not match with the value of the diameter
obtained with a two points measuring instrument; that unlike Archimede cannot detect
circularity errors due to a number of deformation lobes greater than 2 (the case of an
irregular ellipse).
When we use a micrometric gauge, a caliper or bore gauge for inner diameters, we are
using a two points measuring instruments. Such instruments are unable to detect the
circularity error in case of parts which have an odd number of lobes (3 or 5 lobes), also
if dierent angular position’s measurements are taken. With the two points measuring
instruments it is possible to estimate the circularity error only in the case of parts which
have an even number of deformation lobes (ellipses).
11
IN CASE OF IRREGULAR CYLINDERS IS IT POSSIBLE TO
MEASURE THEM WITH THE ARCHIMEDE HR?
It is possible to measure an irregular cylinder only by repeating the measurement
on dierent arcs of the same cylinder, to obtain the value of the Average Diameter.
It is impossible to perform a single-shot measurement to obtain an accurate
diameter value.
In the picture above, a theoretical cylinder is shown with two flat surfaces, that make
it a cylinder with a polygonal deformation. In this case, the value of the diameter
calculated by Archimede in the position shown in the picture, does not coincide with any
comparative measurement obtained from two points measuring instrument as a caliper
or an outside micrometer.
In fact, when the measure of the cylinder shown above is taken with a caliper, the
diameter is obtained the diameter taking into account only one of the two flattened
areas, because the measurement is made taking the distance on two diametrically
opposite points.
With Archimede instead it is possible to determine the measure of the average diameter
(inscribed) of the circumference passing through both flattened areas, as shown in the
picture.
Archimede returns only and always the diameter measurement of circles, while a two
points measuring device as a caliper, an outside micrometer or a two points bore gauge,
returns only the measurement of lengths.
The measurements taken at two points and those taken with Archimede may be
coincident only if the measured piece has a limited form error, as indicated in Tab.1.
12
HOW TO USE THE
ARCHIMEDE HR
It is suggested to use the Archimede instrument following these two modes:
• according to a vertical plane perpendicular to the axis of the contact wheels
(ie the axis of the workpiece to be measured horizontally). [Pic. 1]
• according to an horizontal plane perpendicular to the axis of the contact wheels
(ie the axis of the workpiece to be measured vertically), using the central and lateral
mechanical stops for a more accurate measurement and to avoid the arms bending due
to the weight of the instrument. [Pic. 2]. Using this mode, the operator must more
carefully place the instrument onto the piece to measure, controlling the pressure
applied. This pressure has to be kept between 1÷2 kg, to avoid any bending in the arms.
Any other measuring mode between the two staded above, it is not to be
performed; although it is possible to proceed with the measurement of objects that are
not well aligned with the floor, the resulting measure would not be accurate and may be
aected by errors due to various factors - mechanical strain on the instrument arms - and
the diiculty of maintaining the contact wheels resting on the surface to be measured.
In any case when it is possible, it is recommended the use of mechanical stops (both in
horizontal and vertical mode).
For a better measurement accuracy, it is suggested to take the measure placing the
instrument on the piece to measure, first on the central hub, than, rotating it on the arms.
[Pic. 1]
According to a vertical plane
perpendicular to the axis of the
contact wheels (ie the axis of
the workpiece to be measured
horizontally)
[Pic. 2]
According to an horizontal plane
perpendicular to the axis of the
contact wheels (ie the axis of
the workpiece to be measured
vertically).
13
FUNCTIONS MENU
Power on / o
To turn on and o the ARCHIMEDE, press the ON / OFF button on the control panel.
Zero setting of Archimede
The zero setting procedure of the instrument is automatically performed every time
it is turned on. The operator holding the instrument with the measuring arms joined,
turn the instrument on by pressing the ON/OFF button and wait till the following text
appears on the display:
OPEN FROM JOINED ARMS
The operator then slowly extends the instrument arms until the acoustic signal “beep”
confirm the zero setting achieved.
It is now possible to perform measurements of both external and internal diameters. To
make a new zero-setting, acces the MENU / SETTINGS / ZERO SETTING / INDEX, follow
the instruction shown on the display and wait for the acoustic signal to confirm the
operation.
Reading and measurements
Aer the Archimede has been turned on, the display shows the serial number; meanwhile
zero-setting has been performed (see above), the instrument is ready for measurements:
the display will show the following texts spread \over 3 raws:
Raw 1 Ø EXT. mm or Ø EXT. in
in the second raw appears in a larger font, the value of the calculated diameter of the
best fit circle, tangent to the instrument three support points
Raw 2 936,38
In the third raw is shown:
Raw 3 M X
where “X” indicates the number of readings that have been saved, to be used for the
calculation of the average diameter.
14
A small icon on the display, on the right; shows the battery charge status.
= full charge = half charge = low battery
When the battery is fully loaded, please disconnect it from the electrical power.
The maximum number of readings that can be stored is 12.
The instrument is able to recognize the angle between its arms and then arrange
automatically the measurement of an internal or an external diameter. The display
shows the mode of measurement with the two following written:
Line 1 EXT or INT
Archimede measuring range is:
External diameters: minimum: 500 mm
maximum: 6000 mm
Internal diameters minimum: 1000 mm
maximum: 6000 mm
In case of reading out the measuring range, the display shows the following text:
OVER RANGE
15
Calibration and factory settings
The instrument Archimede is calibrated at 20° ± 1°C reference temperature: this
calibration is called “factory set”.
“OT MODE” calibration
When using Archimede in particular environmental conditions (very high or very low
temperatures) it is necessary to calibrate the instrument for a more accurate and precise
measurement, as illustrated below:
1. Switch on the instrument, position it by opening the arms at 180° and resting the
two wheels and the central support wheel on the surface plate or on the straight edge,
previously leveled.
2. Press the MENU button, select “INITIALIZE” and then “OT MODE”: the display will
show the message: “Place Archimede at 180 ° within 10 seconds”.
3. Aer some seconds it will be displayed the “CALIBRATION DONE” message with an
acoustic beep that indicates the completion of the instrument calibration.
4. The display will show the continuous angle readouts, showing also the icon OT in the
lower right corner. This reminds the operator that the instrument is working in “Out of
Temperature” mode, not according to the factory calibration, in order to ensure more
accurate measurements at the current temperature conditions.
When the instrument is turned o, the factory settings are restored and the mode
“OT MODE” disabled. It is possible, without turning o the power, to disable the “OT
MODE” via MENU / INITIALIZE / OT MODE / DISABLE.
16
Readings store
It is possible to store up to 12 readings, and obtain the arithmetic mean. In
order to obtain this, once achieved a stable measurement, press the (SAVE)
button on the right arm of the instrument:
The display will show the actual value of the diameter. Pressing the (SAVE)
button the current measurement is stored in memory, and in the bottom right
corner is shown the number of stored measurements.
Reading of average diameter
To view the stored measurements, press MENU / MEMORY / VALUE SAVED on the
control panel. The measures will be displayed listed as follows:
1 - 545.76 mm ext
2 -
To view the arithmetic mean of the stored readings, press the MENU / MEMORY /
AVERAGE VALUE on the control panel.
Clearing memory
To clear the instrument memory, thus erasing all the readings previously stored,
select MENU / STORE / CLEAR MEMORY. An acoustic signal (beep) will confirm the
clearing completion.
17
Rotation of the messages on the display
To ease the reading on the display under particular conditions of measurement, a
function of rotation of 180 ° of the shown messages on the display is provided, pressing
the button. To return to the normal display setting, press the button again.
Measurement units
To set the measurement units, select MENU / SETTINGS / MEASURES / UNITS: then
select the preferred measurement units between mm and inches.
Measurement type
You can select to display the measurements as diameters or angles. Press MENU / SETTINGS /
SIZES /MEASUREMENT TYPE and choose between diameters and angles.
In the angular measure mode, you cannot store any measurement. To get again
the saving measures displayed, switch back to the DIAMETERS mode, selecting MENU /
SETTINGS / SIZES / MEASUREMENT TYPE.
Absolute or Relative Measurement (ABS / REL)
The instrument by default, supported on three points aligned onto a straight surface,
returns a measure of 180 ° absolute angle (ABS). To use a “relative” (REL) reference
rather than an absolute one (ABS); press the button for 5 seconds and wait until the
beep: the relative mode will be indicated with the message (REL) shown on the display in
the top right. To restore the measuring absolute (ABS) mode, press again for 5 seconds
the button and wait.
18
Reading of maximum and minimum values
In order to make the diameters measurement easier, especially when the instrument
is not easy to reach, the “Minimum Value” reading function has been developped:,
that shows on the display the minimum value detected by the instrument during the
measuring process. This function is activated by pressing the button on the arm of
the instrument.
When measuring an outer diameter, in all measurements taken the minimum value
reached appears and “minimum” is displayed in the lower le. To exit this function,
press the on the control panel.
It is possible, in the same way, to read the maximum value by activating the
“maximum” function. To access this feature, press the button 3 times, until the in-
strument display shows the message “maximum” on the bottom le. To exit this fun-
ction, press the button on the instrument arm.
MAINTENANCE AND PERIODIC CHECKS
The Archimede instrument does not requires special maintenance operations. It is
recommended, however, to proceed to the regular cleaning of the wheels and of the
central hub. You can easily clean it with compressed air or repeatedly applying and
removing a strip of adhesive paper tape in order to remove dust and metal chips that
may aect the support of the hub and thereby create measurement error.
To ensure good reliability and accurate measurements, it is recommended a periodic
inspection each 12 months. For any questions or information on the maintenance and
calibration of the instrument our technical department is available.
The “minimum value” function is to be
used when the instrument is used wi-
thout mechanical stops. With a slight
rotation of the instument (based on the
central hub), variable measurement are
obtained. The minimum diameter is the
exact value of the cylinder to be measu-
red.
19
IMPORTANT REMARKS
FOR A PROPER MEASUREMENT
The Archimede instrument measures the circumference diameter fitted through three
points of contact identified by the instrument supports (the central one and the two
wheels at the ends of the arms). Should be taken in mind that, in case of shape error of
the object to be measured, will be obtained measurements influenced by the same error.
Shape error examples:
Ideal circumference
The solution to have a valid measurement is to use the “average” function, provided by
the instrument; thus measuring the object at several arcs in order to obtain the averaged
value of the diameters measured.
To perform a correct measurement it’s very important the way how the instrument is
used. The two arms in titanium are the most sti solution that can be achieved: although
the load generated by the operator onto the Archimede arms while measuring, produces
a minimum deflection, that may result in a variation on the angular measurement.
To avoid and limit this influence, it is strongly recommended to hold the instrument
without pressing the arms against the object to be measured (pressure max. of the
operator 1 ÷ 2 kg) using when possible the mechanical stops.
The measured diameter
will be lower then the ideal
circumference.
The measured Diameter will
be bigger then the ideal
circumference.
20
ADDITIONAL FUNCTION
RELATIVE ZERO SETTING
• Pushing down either one of the two Save buttons for about three seconds,
you will enter in the Relative zero configuration mode on the instrument.
• Hold Archimede for about ten seconds in the desired position
for the relative zeroing.
Aer this procedure you will automatically return to the Measurement screen where the
saved position will correspond to the new zero in the instrument. On the screen the label
REL will appear at the top right to make it clear that the instrument is in the Relative zero
mode.
You can also save measures with relative zero and display them on the soware as usual.
The value displayed on the soware will correspond to the actual value of the
measure and not to the relative value.
To exit from the Relative zero mode just press either one of the two Save buttons for
about three seconds. If the instrument is turned o while it’s in the Relative zero mode,
this mode must be configured again when you switch the instrument on.
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