HYDAC HMG 3000 User Manual

PORTABLE DATA RECORDER

HMG 3000

User Manual

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Table of Contents

1 Tasks and Functions of the HMG 3000 .......................................................4

2 About Your HMG 3000..................................................................................7

2.1 Included with the HMG as Supplied......................................................7

2.2 Power Supply........................................................................................7

3 Technical Safety............................................................................................7

3.1 General Safety Precautions..................................................................8

4 Starting the HMG 3000 Up............................................................................9

4.1 Operating Elements ..............................................................................9

4.2 Connectors .........................................................................................10

4.3 Switching the HMG 3000 On ..............................................................11

5 Getting Started Guide.................................................................................13

6 Detailed Operating Instructions.................................................................17

6.1 Settings Menu.....................................................................................17

6.1.1 Changing the Settings of the Measurement Channels ...........17

6.1.2 Changing Display Settings .....................................................27

6.1.3 Zeroing Measurement Channels ............................................29

6.1.4 Changing the Initial Setup ......................................................31

6.1.5 Administer settings (save, load, ...) .......................................33

6.2 Recording Menu .................................................................................35

6.2.1 Starting a Recording ..............................................................35

6.2.2 Viewing Recordings ...............................................................51

6.2.3 Deleting Recordings...............................................................62

6.3 Extras Menu........................................................................................63

6.4 SMART Sensors .................................................................................65

6.4.1 Connecting SMART Sensors .................................................65

6.4.2 SMART Sensors Menu ..........................................................66

6.5 Technical Specifications................................................................................69

7 Cleaning.......................................................................................................70

8 Accessories.................................................................................................71

9 Connection of HMG Components..............................................................73

9.1 Pin assignment....................................................................................74

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1 Tasks and Functions of the HMG 3000

The HMG 3000 portable data recorder is a hand-held unit for simple measurement and data
capturing tasks involving hydraulic and pneumatic systems. Applications extend primarily to
maintenance and servicing, troubleshooting and test rigs.

The HMG 3000 can concurrently evaluate signals from up to 10 sensors. The unit features
input jacks for connecting the sensors; if necessary this number can be doubled using a
adapter for measurement operations involving more than 5 sensors. HSI sensors (HYDAC
Sensor Interface) are HYDAC sensors for pressure, temperature and flow rate with automatic
sensor recognition.

You also have the option of connecting SMART sensors to the HMG 3000. These are the
new generation sensors from HYDAC, capable of outputting several different measured
variables. These sensors are also automatically recognized by the HMG 3000 via HIS, and
the measured values including the measurement unit are shown in the display.

The HMG 3000 can render up to 32 measurement channels.

Depending on the sensor type the sensor features an internal memory providing for the
storage of recorded measurement data on a long-term basis. In addition, depending on the
sensor type preset parameters can be changed and stored in the internal memory as a
sensor configuration.

Older model HYDAC sensors or standard sensors of other manufacturers commercially
available can also be used. However, these sensors do not feature any automatic sensor
detection, consequently the initial set-up has to be entered by hand.

The HMG 3000 is user-friendly by virtue of its easy-to-access selection menus leading to all
of the unit’s functions and settings. The unit features a combination keypad for entering
numeric values and text in a fashion similar to that of mobile phones.

The HMG 3000 was designed in particular for capturing typical measurement values
(pressure, temperature, volumetric flow rate) in hydraulic and pneumatic systems. A
variety of other measurement tasks can be performed by virtue of additional inputs for
voltage measurement. Example: checking the actuation of a switching valve or plotting
the characteristic curve of a valve setpoint. In addition, it is also possible to determine
differential values between the measured values of individual sensors. One example of
this is taking a volumetric flow measurement using a differential pressure orifice plate.

In addition to the analog measurement inputs, the HMG features two digital outputs, enabling
frequencies or speeds to be recorded, thus expanding the unit’s range of potential
applications.

When taking measurements of rapid, dynamic machine processes, all 8 analog input
signals can be concurrently captured at a rate of 0.5 ms.

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One special feature of the HMG 3000 is its ability to record measurements of the highly
dynamic processes in a machine. To this end, two input channels are featured which are
capable of recording measured values at a rate of 0.1 ms. It goes without saying that this
feature is dependent on the use of suitable, fast-acting sensors.

The most attractive feature offered by the HMG 3000 is its ability to record the dynamic
processes of a machine in the form of a measurement curve and render them as a graph —
on line and in real time.

The HMG 3000 is equipped with specially developed software providing for fast data
collection and processing. A measurement curve can comprise up to 500,000 measured
values. The HMG 3000’s measured value memory is capable of storing at least 100 of these
measurement curves.

In addition to enabling simple measurement curves to be recorded, the HMG 3000 also
features other functions enabling event-driven measurements to be taken and event logs to
be recorded. Various trigger options are available for triggering events.

Apart from measurement curves, the HMG 3000 can store user-specific settings (user
profiles). The main advantage of this is enabling identical measurements of various

equipment items to be repeated for the purpose of preventive maintenance. All the user has
to do is retrieve the respective user profile from the HMG 3000’s memory.

In addition to the analog measurement inputs, the HMG features two digital outputs,
enabling frequencies or speeds to be recorded, thus expanding the unit’s range of potential
applications. Individual measured values can be displayed in a large format (7-segment
format), enabling them to be read at an extended distance.

The HMG 3000 also provides for a variety of user-friendly features for displaying, evaluating
and processing measured values:

• Table

• Graph

• Scaling

• Ruler

• Tracker

• Zoom

The HMG 3000 communicates with a computer via a USB or serial port. HYDAC offers

HMGWIN 3000, the matching software for the HMG 3000 which comes standard with the

unit, for convenient post-processing, rendering and evaluation of measurements at your
computer. It also enables the HMG 3000 to be operated directly from your computer.

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The HYDAC software CMWIN also comes standard with the unit. This software enables

you to communicate directly from your computer with SMART sensors connected to the
HMG 3000.

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2 About Your HMG 3000

2.1 Included with the HMG as Supplied

• HMG 3000

• Power supply providing for 90 – 230 V

• Manual

• CD-ROM containing USB drivers and HMGWIN 3000 and CMWIN

(software for analyzing measurement data and sensor communication)
in addition to other product information

• USB connector cable

2.2 Power Supply

The HMG 3000 comes with an internal NiMH battery. To charge the battery, simply connect
the power supply furnished with the unit (see connectors of the HMG 3000). The battery is
fully charged after ca. 5 hours.

A direct current supply (12 – 30 V DC) can be connected to the power input socket for
operating the HMG or charging the battery.

When connecting the power supply to the input socket make sure that +UB is present at the
inner contact of the plug and 0 V at the outer contact. A JEITA RC 5320-5 plug, for example,
is suitable for this purpose; it is available in most electrical/electronics shops.

3 Technical Safety

The individual components of the HMG 3000 portable data recorder and the assembled unit
are subject to strict quality assurance inspection and testing. Each HMG 3000 undergoes
outgoing testing. This ensures that when supplied the unit is free from defects and complies
with the designated specifications.

The series HMG 3000 portable data recorders are maintenance-free and work perfectly
when used under the conditions specified. If, however, you do encounter problems, please
contact your HYDAC representative. Any tampering with the data recorder will cause all
warranty claims to become null and void.

Compliance with European Standards

The HMG 3000 series portable data recorders feature the CE mark and thus comply with all
relevant German regulatory requirements and European standards currently in effect
pertaining to the operation of these units. This ensures compliance with currently valid
regulations pertaining to electromagnetic compatibility and the provisions of the Low-Voltage
Directive (73/23/EEC).
This product complies with the provisions of the following European standards:
EN 61000-6-1 / 2 / 3 / 4

All technical details are subject to change without notice.

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3.1 General Safety Precautions

The HMG 3000 series Portable Data Recorder can be operated safely provided it is used
in accordance with its proper, designated use. Please maintain strict adherence to the
following safety guidelines in order to preclude hazards to the user and damage to
property and surroundings as the result of improper use:

• The HMG 3000 may not be used unless it is in perfect condition/working order.

• Strict adherence is to be maintained to the usage instructions. Operations involving

adjusting the zero point in particular can lead to dangerous situations. For more

information, please refer to Zeroing of Measurement Channels.

• Heed the specifications on the rating plate.

• Troubleshooting and repair work may only be done by HYDAC’s Service Department.

• Adherence is to be maintained to all relevant generally recognized safety regulations.

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4 Starting the HMG 3000 Up

4.1 Operating Elements

1

2

3

4

5

6

7

On/Off button

Brightness setting of the display

Esc

For cancelling an entry or going Back

step by step

Shift key

Switches the keypad to a textpad
when pressed; the textpad is active
only as long as the Shift key is
pressed.

Text/numeric keypad

Numbers and letters can be entered
via the combination keypad in a
fashion similar to that of mobile
phones.

Numerals: 0 to 9; “.” (decimal separator) and “-“ (minus)
Text entry: a, b, c, ... x, y, z and A, B, C, ... X, Y, Z;
To insert special characters:
To insert spaces:
To delete characters:
Line break:

Tip:

SHIFT + OK (simultaneously)

SHIFT + INS (simultaneously)

SHIFT + DEL (simultaneously)

SHIFT + "1" (if necessary, several times for /, %, $ ...)

To accept characters: release the Shift key or press the right arrow of the

5-way navigation key.

To jump directly to the function line: simultaneously press the Shift key and the

down arrow of the 5-way navigation key.

Graphic display

Display of the menu and operating functions, measured values and measurement
curves

5-way navigation key

To navigate step by step in the display: OK key for inputting, concluding, accepting or

storing an entry

1

2

3
4

5

INS = insert; DEL = delete;

6

7

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4.2 Connectors

USB

DC IN

A B C D I I

E F G H J Y adapter

RS232

A - D

4 sensor input jacks for up to 8 analog sensors or up to 4 SMART sensors

(channel A – D and E – H*), e.g. for sensors for measuring pressure,

E - H

temperature or flow rate.
The four input jacks can be doubled by plugging in Y adapters.

I / J

1 or 2 input jacks for

-2 digital signals, e.g. for frequency or speed measurements (channel I, J)

-1 voltage input ( - 10 V to + 10 V, channel H*)

DC IN

Female connector for power supply

USB

1 USB connector

RS232

1 serial port

H*: Channel H can be used for sensors with an analog signal as well as for voltage

measurements of -10 V to +10 V.

(for pin assignment, see section 9.)

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4.3 Switching the HMG 3000 On

When starting the unit up for the first time the

Welcome start-up screen appears. Select

your language using the 5-way navigation key
(Select or checkmark your option by pressing

OK) and set the current date and time. Select

the desired format, followed by entering the

current date and time via the keypad. Save
your entries via OK, followed by pressing
Continue.

The following appears in the display when
starting the unit up in normal operation:

• Manufacturer

• Designation of the unit

• HMG version

• Date and time

• Battery charge status

The screen switches to measured value
display mode in a few seconds. When sensors
are connected you are shown the current

measured values in the Current Measured
Values menu (see title bar in display). To skip

through the start-up screen more quickly and
proceed directly to the measured values

menu, press Esc or OK.

The following is listed in the measured values
screen (see screenshot): Input channel –
Designation – Value – (Measurement) Unit

The menu bar at the bottom of the screen
(function bar) displays the main menu and
next to that, on the right, the battery charge
status. The main menu contains the following
functions which you can access via the

navigation key (arrow key) plus the OK key.

Settings — for entering or referring to

setting data used for performing
measurements

Recording — for recording a

measurement and graphically rendering
measurement data, e.g. as a curve

Note:
Generally speaking, functions
which can be selected and

executed are blue.

Black means the functions

can’t be selected or executed.

Warnings are shown in red

when incorrect entries are

made.

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Extras — menu featuring the stopwatch,

among other things

plus a function for displaying the Min/Max

values.

Special significance is accorded the

measurement of the Min/Max values, which

is why it is explained in detail below.

Apart from the current measured values, the
HMG captures the minimum and maximum
values (Min/Max values) too, except when
recording a measurement curve. The
minimum value is the smallest value to which
a measured variable has dropped during the
time period under consideration, the
maximum value being the largest value
achieved by a measured variable during this
period. Resetting causes the Min/Max values
to be set to the current measured value. This
is done jointly for all sensors.

The time period always begins when the
Min/Max values are reset. Resetting the
values is prompted by the following
situations:

• Switching the unit on

• Selecting and activating Reset in the

menu bar

• Connecting or removing an HSI sensor

• Modifying the sensor settings

• While recording an event log

• When concluding recording

Before resetting the Min/Max values it is
frequently necessary to determine when the
Min/Max values were last reset. To do this, go

to Extras in the function bar and then About
HMG 3000.

Note:
Even if the Min/Max values
aren’t shown in the display
HMG captures them in the
background.

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5 Getting Started Guide

This Getting Started Guide outlines the basic steps for conducting a simple measurement
(measured values shown in display) and recording a measurement curve (graph of measured
values). These examples involve pressure measurement using 2 pressure transmitters with

sensor detection (HSI sensors). For a detailed description of all the settings, see Detailed
Operating Instructions.

The examples are based on the factory settings of the HMG 3000. Simply follow the
steps described here. If you don’t know the status of your HMG 3000 because there
might be more than one user in your company using the HMG, you can simply restore

the unit to its condition as supplied (see Administration Settings — Restore factory
settings).

Preparation in Advance of Performing a Measurement
First charge the batteries or connect the power supply as described in Power Supply. Two

HYDAC HDA 4748-H-0400-000 pressure transmitters with automatic sensor detection are
used in the following example.

Example of a Simple Measurement
Using Two Pressure Transmitt er s

Integrate the two pressure transmitters
hydraulically in your equipment and connect
the two pressure transmitters using the
sensor connector cables, e.g. to jacks A
and B of the HMG 3000.

After the HMG 3000 is switched on it jumps

to the Current Measured Values menu. The

menu bar (function bar) contains various
functions providing you direct access to the
three main menus:

- Settings - Recording - Extras

and to the display of the Min and Max

values.

Title bar

Function bar

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When HSI sensors featuring automatic
sensor detection are used, the HMG
automatically detects the measurement
range and the unit of measurement of the
two connected pressure transmitters and
shows them in the display with the current
measured values. You can also have the
minimum and maximum values for the
sensors displayed.

To hide or unhide the Min/Max display,
actuate the right arrow of the 5-way

navigation key until Min/Max is highlighted in
blue and then press the OK key. This causes

the Min/Max values of the sensors to be

additionally displayed. Pressing the OK key

again causes the Min/Max display to be
switched off.

When the Min/Max values are shown, Reset

appears in the function bar, enabling you to
reset the Min/Max values as needed. Select
them using the arrow keys (blue highlighted)

and then press the OK key: the Min/ Max

values are reset.

The measured values can also be displayed

in a 7-segment pane. To do this, go to

Settings in the function bar and then press
OK. In the Settings menu, navigate to
Change display settings using the 5-way

navigation key, and then confirm via OK (cf.

screenshot of two-pane display on the next
page).

Now select the second item, Measured
value rendering. Measured value table is
the default setting here. Press OK. A drop-

down list appears in which you navigate to 2
display panels using the arrow keys,

followed by confirming via OK. To return to
the measured value display press Esc twice.

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The HMG now shows the measured values
in the 7-segment display panes. Depending
on the setting, the Min/Max values are
shown in addition to the current measured
values.

The Recording menu is used for recording

measurement curves. During recording, the
measured values are recorded for a certain
period of time, stored and then shown as a
graph.

Example of Recording a Measurement
Curve:

The function bar of the Current Measured
Values menu contains the item Recording.

Select it using the 5-way navigation key,

followed by pressing OK. In the Recording
menu that follows, select Start recording
and confirm via OK.

In the menu that follows, Start Recording,

you are shown the default settings for
recording a measurement curve. In our

example, we want to generate a Simple
measurement curve with two sensors at
channels A and B with a sampling rate of

1 ms and a Recording time of 30 s. Then
measurement is to be concluded.

Simple measurement curve is already set

in the menu. For the other settings, proceed
as follows:

Using the arrow keys of the 5-way navigation

key, select the third item, Sampling rate. OK
causes a drop-down list to open in which
you select a sampling rate of 1 ms, followed
by confirming via OK. This causes you to
automatically proceed to the Recording
time line. Press OK. Scroll in the drop-down
list using the arrow keys to 30 seconds,
followed by confirming via OK.

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In the Recording option line, select End
when time has elapsed in the same

manner.

Your screen now shows the settings for
recording measured values made by you (cf.
screenshot at right). To double-check your

settings, refer to the recorded data selected

by you above the function bar.

Now you can start recording via Start in the
function bar + OK. A progress bar shows

you the status of your measurement. The
function bar offers you the option of having
the measurement curve plotted or the current
value shown while recording.

Graphic rendering provides for a faster

visual impression of the changes in the
measured values. To have the measurement
curve displayed while recording, select

Graph + OK. The screenshot at the right

shows you the curve plotted for our example.

When recording is concluded, you have the
option of storing or discarding the
measurement. To store the recording, select

Save and confirm via OK. The HMG

automatically assigns a name and a
consecutive number, which can be
subsequently changed by you as needed.
For our example, accept the name

suggested by the HMG and save via OK.

You can view any stored recording again or
delete it as you like. For more information on

this, refer to Detailed Operating Instructions.

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6 Detailed Operating Instructions

6.1 Settings Menu

Submenus of the Settings menu:

• Change settings of measurement

channels

• Change display settings

• Zero measurement channels

• Change initial setup

• Administer settings (save, load, ...)

• Administer sensor configuration

(not visible unless the configuration of a
SMART sensor has been read out, see
section 6.4.2.5)

6.1.1 Changing the Settings of the
Measurement Channels

Select Change settings of measurement
channels to obtain a listing of all the

channels available in the HMG (see
screenshot). There is a checkbox next to
each of the channels enabling you to switch

the input on or off (+ OK key). Activated
channels are marked by an “X”.

To the right of the checkbox is the

measurement range setting, the unit of

measurement, and, as applicable, a

designation for the sensor, e.g. "System

pressure".

The various options available for channels
A to H are demonstrated here using
channel A as an example. Select the

measurement range entry to the right of

the channel using the arrow keys followed

by OK. You now proceed to the menu

window of the channel selected. To enter a

designation, press OK again and then

enter it in the box using the combination

keypad, followed by OK.

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In the Mode menu you now have the option
of Automatic detection (HSI) and Manual.
The Automatic detection (HSI) option is

used for HYDAC sensors featuring automatic

sensor detection. The Manual setting is

used for adapting sensors featuring standard
analog signals to the HMG (e.g. 4-20 mA).

However, there are applications in which
entering settings by hand is useful, also for
HSI sensors. For example, by entering
settings manually for a pressure
measurement you can have proportional
variables, e.g. the ”force”, shown on the
HMG.

Manual mode also provides for the following

settings:

• Input signal

• Upper and lower measurement range

• Unit (of measurement)

• Decimal format

As soon as you select one of these items, a
drop-down list appears or a box appears for
entering your settings.

For Input signal you can choose in the drop­down list between HSI (HYDAC Sensor
Interface) and various standard analog

signals (using the arrow keys). To set the

Lower and Upper measurement range,

enter the respective limits via the
combination keypad.

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A drop-down list is also provided for

selecting the Unit (of measurement). You
also have the option of defining your “other
unit” (uppermost line of the drop-down list).
The cursor then jumps to the input box and
a small triangular arrow appears as the
insertion point. Enter the new unit using

the combination keypad, e.g. ”kPa” for
kilopascal.

To enter additional characters, move the
triangle insertion point to the desired
position and enter the characters. Conclude

your entry via OK so that your unit of

measurement is stored.

Decimal format: Here you can specify how

many decimal places are to be used when
recording and displaying the measured
values.

In addition to the settings described above,

Channel B has two further measurement
options. In the Mode drop-down menu you
now also have the menu options Pressure

difference dP and Orifice measurement
Q=f(dP). With Pressure difference dP the

HMG 3000 gives you the opportunity to
display the difference in pressure between
channel A – channel B with a very high
degree of accuracy. This can be used, for
example, to determine if a filter is clogged,
by measuring the pressure differential.

The function Orifice measurement Q=f(dP) enables you to carry out a flow rate

measurement by measuring the differential pressure at a flow rate measurement orifice (e.g.
HYDAC EVS 1000). For both these modes HYDAC HSI pressure transmitters with the same
measurement range must be connected to channel A and channel B. The differential
measurement range is produced automatically, being ± 10% of the measurement range of
the pressure transmitters connected. The accuracy of the HSI pressure transmitters is
≤±0.5%FS. This means that one 100 bar pressure transmitter might measure 50 bar
pressure as being 49.5 bar, and another might measure it as 50.5 bar. These pressure
transmitter errors can be compensated for by recording a correction curve. After correctly
recording a curve, the accuracy for differential measurement is ≤±0.1% of the differential
measurement range.

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Example:
For both 100 bar pressure transmitters there is a differential measurement range of

-10 – +10 bar, in other words a measurement margin of 20 bar. The accuracy of ≤±0.1%

refers to this measurement margin. The pressure differential can therefore be measured with
an accuracy of ≤±0.02 bar.

To measure a pressure differential, select
the item Pressure differential dP. Then you
find an item Organise curves. Here you can

plot up to 3 curves for 3 pressure transmitter
pairs. If a curve for a pressure transmitter
combination already exists, you can quit the

menu again by selecting Back or the Esc

key. The HMG 3000 automatically selects
the appropriate curve. If you quit the menu
and the HMG 3000 detects that no curve
exists for this combination, you will get the
message shown on the right. You can now,
with less accuracy, measure the differential
or you call the menu item again to record a

new curve under Organise curves.

Upon selecting Organise curves, a screen

appears which allows you to record a new
curve, or you see information on curves
which already exist. At this point you can
also delete existing curves if they are no
longer required. If curve 1 already exists,

navigate to this field and press the OK key.

You can now, for example, select

Characteristic curve 2, Not available and

then record a curve. To record the curve you
must connect both pressure transmitters to
the HMG 3000 at channel A and channel B.
When doing this, identify which pressure
transmitter has been connected to channel A
and which to channel B, since the pressure
transmitters must be re-connected in the
same way later when taking measurements.

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Connect the pressure transmitter
hydraulically so that the two instruments are
subjected to the same pressure. The ideal
for recording curves is connecting to a test
rig on which you can increase the pressure
slowly from 0 bar to the full measurement
range of the pressure transmitter and back
again.
However, the minimum requirement is to
record the curves/measured values in the
pressure range in which the differential
measurement is to take place later.

In the example above (to measure the filter
contamination level) both pressure
transmitters might be fitted to the inlet side of
the filter, e.g. using T-fittings and then, with
the machine running, the curve could be
recorded.
When these pre-conditions are in place,

select Record characteristic curve. This

brings up a display showing 0 to 100% of the
whole measurement range. If you increase
the pressure you will see from the blue bar
that measured values are being recorded in
this pressure range.

If the measured values remain under the red
line, this means that not enough values have
been recorded in this range. To achieve
maximum accuracy for differential
measurement, the recorded measured
values should at least be in the area
between the red and the green line. After

this, select Stop recording and you can quit

the menu. The curve is now automatically
taken into account for the differential
measurement using these two pressure
transmitters.

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In order to measure the flow rate using a
differential pressure measurement at a flow

rate orifice, select the item Orifice
measurement Q=f(dP). Then select the

number of decimal places and the unit (of
measurement).
A flow rate orifice is supplied with information
showing the correlation between pressure
differential and flow rate. For example, on a
HYDAC EVS 1000 it says: calibration factor

4.87 bar at 350 l/min. Enter these values

under the flow rate and pressure.

Here again the menu Organise curves appears, (for a function description and handling,
see Pressure differential dP above). Curve recording can be carried out exactly as described

above.

If you are using a HYDAC EVS 1000 flow rate measurement orifice, you can also use this to
record curves. On the EVS 1000 there are 2 pressure ports before the orifice (ports 1 and 2)
and one after (port 3).

To make a recording, connect the pressure transmitter from channel A to port 1, and the one
from channel B to port 2. To start measurement you need only then to change the pressure
transmitter from port 2 to port 3.

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Input channels I and J are for digital signals.

As the input signal you can choose between

Count pulses and Frequency signal. There

are many possibilities for this, e.g. speed
sensors, proximity switches, pulse
generators, flow rate measuring instruments
with a frequency signal, HYDAC HDS 1000,
to name only a few. As in the case of the
analog sensor inputs, settings can be
manually entered for the input signal, unit of
measurement and decimal format.

In addition to these settings, a factor has
to be entered which is required for
conversion to the desired unit of
measurement.

Another special feature is the inputting of the

Upper measurem. range. Frequencies of up

to 30000 Hz can be measured on channels I
and J, consequently a scale from 0 to 30000
is possible in the graphical display. If, for
example, you record a speed of up to 1450
rpm, an awkward Y-axis scale will result in

the graph. If you enter "1500" as the Upper
measurement range for this speed

measurement, for example, the Y-axis in the
graph will be scaled from 0 to 1500 rpm.

In this case entering the upper measurement range is just a means of limiting the scale of the
Y-axis in the graphical display. You should set this value as close as possible to that of the
expected measured value in order to get the best possible graphical display.
If measured values exist which are larger than the upper measurement range, these are not
lost. The scale of the Y-axis can be changed again in the graph at any time later on.

N.B.

The measurement range of the frequency entries is 1 Hz to 30000 Hz. If, for example, the
rpm of a motor is recorded and this motor stops abruptly, the last rpm can still show in the
display for up to 2 seconds, depending on the measurement system, before 0 is displayed.

Edition 11/2007 - V02 R01-S02 Stock no.: 669712