GHM-Messtechnik GREISINGER GMH 3181 Series User manual

H61.0.3X.6C-01
GHM Messtechnik GmbH • Standort Greisinger
Hans-Sachs-Str. 26 • D-93128 Regenstauf
+49 (0) 9402 / 9383-0 +49 (0) 9402 / 9383-33 [email protected]
User’s Manual
Handheld Digital Precision Manometer
GMH 3181-...
Version 6.5
WEEE-Reg.-Nr. DE 93889386
GMH 31 Series
Druck / Pressure

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 2 of 16
CONTENTS
1GENERAL NOTE....................................................................................................................................3
2SAFETY..................................................................................................................................................3
2.1 INTENDED USE....................................................................................................................................3
2.2 SAFETY SIGNS AND SYMBOLS...............................................................................................................3
2.3 SAFETY GUIDELINES............................................................................................................................3
3PRODUCT SPECIFICATION ..................................................................................................................4
3.1 SCOPE OF SUPPLY ..............................................................................................................................4
3.2 OPERATION AND MAINTENANCE ADVICE................................................................................................4
4HANDLING .............................................................................................................................................5
4.1 DISPLAY.............................................................................................................................................5
4.2 BASIC OPERATION ..............................................................................................................................5
4.3 CONNECTIONS....................................................................................................................................6
4.4 POP-UP CLIP.......................................................................................................................................6
5START OPERATION ..............................................................................................................................7
6CONFIGURATION ..................................................................................................................................7
7REMARKS TO SPECIAL FEATURES....................................................................................................8
7.1 DIFFERENT KINDS OF MEASURING:„RATE-SLO,-P.DET,-FAST“...........................................................8
7.1.1 rAtE-Slo: Standard Measuring ....................................................................................................8
7.1.2 rAtE-P.dEt: Peak detection .........................................................................................................8
7.1.3 rAtE-FASt: Fast filtered measuring..............................................................................................9
7.2 SEA LEVEL CORRECTION (ONLY FOR GMH 3181-12 )...........................................................................9
7.3 AVERAGING FUNCTION........................................................................................................................9
7.4 POWER OFF TIME................................................................................................................................9
7.5 ALARM ...............................................................................................................................................9
7.6 REAL TIME CLOCK ..............................................................................................................................9
8OPERATION OF LOGGER...................................................................................................................10
8.1 „FUNC-STOR“: STORING SINGLE MEASUREMENTS ..............................................................................10
8.2 „FUNC-CYCL“: AUTOMATIC RECORDING WITH SELECTABLE LOGGER-CYCLE-TIME ..............................11
9OUTPUT................................................................................................................................................12
9.1 SERIAL INTERFACE............................................................................................................................12
9.2 ANALOGUE OUTPUT –SCALING WITH DAC.0 AND DAC.1....................................................................13
10 INPUT ADJUSTMENT .......................................................................................................................13
10.1 ZERO DISPLACEMENT SENSOR ('OFFS').........................................................................................13
10.2 SCALE CORRECTION SENSOR ('SCAL')...........................................................................................13
10.3 CALIBRATION SERVICES.................................................................................................................13
11 PRESSURE CONNECTION...............................................................................................................14
11.1 DEVICE TYPE WITH ABSOLUTE PRESSURE (GMH 3181-12)...............................................................14
11.2 DEVICE TYPE WITH RELATIVE PRESSURE .........................................................................................14
12 ERROR AND SYSTEM MESSAGES.................................................................................................14
13 SPECIFICATION................................................................................................................................15
14 RESHIPMENT AND DISPOSAL ........................................................................................................16
14.1 RESHIPMENT.................................................................................................................................16
14.2 DISPOSAL INSTRUCTIONS ...............................................................................................................16

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 3 of 16
1 General Note
Read this document carefully and get used to the operation of the device before you use it. Keep this
document within easy reach near the device for consulting in case of doubt.
Mounting, start-up, operating, maintenance and removing from operation must be done by qualified,
specially trained staff that have carefully read and understood this manual before starting any work.
The manufacturer will assume no liability or warranty in case of usage for other purpose than the intended
one, ignoring this manual, operating by unqualified staff as well as unauthorized modifications to the device.
The manufacturer is not liable for any costs or damages incurred at the user or third parties because of the
usage or application of this device, in particular in case of improper use of the device, misuse or malfunction
of the connection or of the device.
The manufacturer is not liable for misprints.
2 Safety
2.1 Intended Use
The safety requirements (see below) have to be observed.
The device must be used only according to its intended purpose and under suitable conditions.
Use the device carefully and according to its technical data (do not throw it, strike it, …)
Protect the device from dirt.
2.2 Safety signs and symbols
Warnings are labeled in this document with the followings signs:
DANGER
Caution! This symbol warns of imminent danger, death, serious
injuries and significant damage to property at non-
observance.

Attention! This symbol warns of possible dangers or dangerous
situations which can provoke damage to the device or
environment at non-observance.
Note! This symbol point out processes which can indirectly influence
operation or provoke unforeseen reactions at non-observance.
2.3 Safety guidelines
This device has been designed and tested in accordance with the safety regulations for electronic devices.
However, its trouble-free operation and reliability cannot be guaranteed unless the standard safety
measures and special safety advises given in this manual will be adhered to when using the device.
1. Trouble-free operation and reliability of the device can only be guaranteed if the device is not subjected to
any other climatic conditions than those stated under "Specification".
If the device is transported from a cold to a warm environment condensation may cause in a failure of the
function. In such a case make sure the device temperature has adjusted to the ambient temperature
before trying a new start-up.

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 4 of 16

2. If there is a risk whatsoever involved in running it, the device has to be switched off
immediately and to be marked accordingly to avoid re-starting.
Operator safety may be a risk if:
- there is visible damage to the device
- the device is not working as specified
- the device has been stored under unsuitable conditions for a longer time.
In case of doubt, please return device to manufacturer for repair or maintenance.
3. When connecting the device to other devices the connection has to be designed most thoroughly as
internal connections in third-party devices (e.g. connection GND with protective earth) may lead to
undesired voltage potentials that can lead to malfunctions or destroying of the device and the connected
devices.
This device must not be run with a defective or damaged power supply unit.
Danger to life due to electrical shock!
4. Do not use these products as safety or emergency stop devices or in any other application
where failure of the product could result in personal injury or material damage.
Failure to comply with these instructions could result in death or serious injury and material
damage.
5. This device must not be used at potentially explosive areas! The usage of this device at
potentially explosive areas increases danger of deflagration, explosion or fire due to
sparking.
3 Product Specification
3.1 Scope of supply
The scope of supply includes:
Measuring device with 9V battery
Operation manual
3.2 Operation and maintenance advice
1. Battery operation:
If ‘bAt’ is shown in the lower display the battery has been used up and needs to be replaced. However,
the device will operate correctly for a certain time. If ‘bAt’ is shown in the upper display the voltage is too
low to operate the device; the battery has been completely used up.
The battery has to be taken out, when storing device above 50 °C.
We recommend taking out battery if device is not used for a longer period of time.
After recommissioning the real-time clock has to be set again.
2. Mains operation with power supply
When using a power supply please note that operating voltage has to be 10.5 to 12 V DC.
Do not apply overvoltage!! Cheap 12V-power supplies often have excessive no-load voltage.
We, therefore, recommend using regulated voltage power supplies.
Trouble-free operation is guaranteed by our power supply GNG10/3000.
Prior to connecting the power supply to the mains make sure that the operating voltage stated at the
power supply is identical to the mains voltage.
3. Treat device and sensor carefully. Use only in accordance with above specification. (do not throw, hit
against etc.). Protect plug and socket from soiling.
_DANGER
_DANGER
_DANGER
_DANGER

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 5 of 16
4 Handling
4.1 Display
1
Main display: shows actual value
2
Arrow points to the chosen measuring unit
3
Secondary display: shows min./max. or hold value
4
SL: appears if sea-level-correction is activated
(only GMH 3181-12)
5
Tara: appears if tara-function is activated
6
Logg: appears if logger function is chosen, flashes while
logger is running
4.2 Basic Operation
On / Off
+
min/max bei Messung:
press short: shows the min./max. value
press again: hides min./max. value
press 2 sec.: clears particular value
Tara, zero-point adjustment:
press short: display will be set to 0
The following measuring will be
relatively displayed to the set tara
value
press 2 sec.: deactivates tara-function
press 5 sec.: Zero-Point Adjustment1)
Set/Menu:
press short: invokes configuration menu
Store/Quit:
press short: hold-function, the last measuring
value will be held in the secondary
display.
press again: hides the value
at active logger: invokes logger functions
Please Note: Activating/deactivating tara clears the max- & min-memories.
1) Zero-Point Adjustment: If there is no pressure or zero-pressure (absolute) applied to the pressure ports the
device will display 0. If there is a permanent deviation (and device is operated
under steady conditions), a permanent zero point adjustment can be carried out. To
carry out the adjustment press button 3 for approx. 5 seconds (Auto Null will be
displayed shortly). The adjustment is done via the OFFSET-value of the sensor
(referring configuration menu).
To recall the manufacturer’s calibration press button 3 for approx. 15 seconds.
Please note: - A zero-point adjustment can only be carried out if the difference between the value on display
is less than 500 digits!
- If a zero point adjustment was carried out the display shows ”Corr” after a restart .
1 2 3
4 5 6
ON
OFF max Tara
Storemin
Set
Menu Quit
1 2 3
4 5 6
ON
OFF max Tara
Storemin
Set
Menu Quit

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 6 of 16
4.3 Connections
Output: Connection for el. Isolated interface adapter or
for analog output (please refer to chapter 9)
Connection for pressure tubes:
„+“ higher pressure (non-existent at GMH 3181-12)
„-“ lower pressure (GMH 3181-12: absolute pressure)
Power supply: the mains adapter socket is located at the left side of the device.
4.4 Pop-up clip
Handling:
•Pull at label “open” in order to swing open the pop-up clip.
•Pull at label “open” again to swing open the pop-up clip further.
Pop-up clip closed
Pop-up clip at position 90°
Pop-up clip at position 180°
Function:
• The device with a closed pop-up clip can be plainly laid onto a table or attached to a belt, etc.
• The device with pop-up clip at position 90° can be set up on a table, etc.
• The device with pop-up clip at position 180° can be suspended from a screw or the magnetic holder
GMH 1300.
Device attached to a belt
Device set up on a table
Device suspended from
magnetic holder
GMH 1300

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 7 of 16
5 Start Operation
Connect sensor, turn on device via key.
After segment test the device displays some configuration:
• If the logger function is not off the time of the integrated clock will shortly be displayed.
• If a zero point adjustment was carried out the display shows shortly „nuLL Corr“.
After changing the battery the clock-setting menu is activated automatically (‚CLOC‘). Check the clock
and adjust, if necessary (p.r.t. chapter 6).
After that the device is ready for measuring.
6 Configuration
To change device settings, press Menu (key 4) for 2 seconds. This will call the configuration menu (main
display: „SEt“).
Pressing key Menu changes between the menus, pressing (key 3) jumps to the referring parameters,
which can be selected with key (key 3).
The parameters can be changed with (key 2) or (key 5).
Pressing Menu again jumps back to the main configuration menu and saves the settings.
Quit (key 6) finishes the configuration and returns to standard measuring operation.
Please note: All here specified values are applying for all devices if there is no explicit mark.
The values for the different types of device can be checked up in chart (page 8)
Menu
Param.
Values
Description
C_log
C_dat
Stor
‚Menu‘

or 
SEt
ConF
Set Configuration: Generic Configurations
Unit
mbar,bar..
Unit: Unit of display
*
*
SL
oFF/on
Sea level correction: on or off (only available at GMH 3181-12)
*
*
Alti
-2000..9999
Altitude: Input of altitude above sea level [m] (only if SL=on)
*
*
rAtE
Rate: Measuring rate (p.r.t. chapter 7.1)
*
*
Slo
Slow measuring rate (4Hz filtered, low power consumption)
*
*
FASt
Fast measuring rate, filtered (>1000Hz)
*
*
P.dEt
Peak detection: fast measuring rate, unfiltered (>1000Hz)
*
*
t.AVG
1-120
Averaging period in seconds, used by the averaging function
*
*
oFF
Averaging function deactivated
*
*
P.oFF
1-120
Auto Power Off time in minutes
oFF
Auto Power Off deactivated
Out
oFF
Function of the output: No output function, lowest power consumption
SEr
Output is serial interface
dAC
Output is analogue output 0...1V
Adr.
01,11..91
Base address of interface
dAC.0
p.r.t. chart
Enter desired value at which the analogue output potential should be 0V
(if Out = dAC)
dAC.1
p.r.t. chart
Enter desired value at which the analogue output potential should be 1V
(if Out = dAC)
SEt
CAL
Set Calibration: Adjustment of Sensor
*
OFFS
p.r.t. chart
The offset of sensor will be displaced by this value to compensate for
deviations in the probe or in the measuring device.
*
oFF
Zero displacement inactive (=0.00)
*
SCAL
-2.000 ...
2.000
The measuring scale of sensor will be changed by this factor [%] to
compensate deviations of temperature probe or measuring device
*
oFF
Scale correction factor inactive (=0.000)
*
1 2 3
4 5 6
ON
OFF max
Store
CAL
min
Set
Menu Quit

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 8 of 16
Menu
Param.
Values
Description
C_log
C_dat
Stor
‚Menu‘

or 
SEt
AL.
Set Alarm: Settings Of Alarm Function
AL.
on
Alarm on, with horn-sound
no.So
Alarm on, without horn-sound
oFF
Alarm deactivated
AL.Lo
p.r.t. chart
Min alarm rail (not when AL. oFF, Sensor-Min is the lower display range
of connected sensor)
AL.Hi
p.r.t. chart
Max alarm rail (not when AL. oFF, Sensor-Max is the upper display range
of connected sensor)
SEt
LoGG
Set Logger: Configuration Of Logger Function
*
*
Func
CYCL
Cyclic: logger function ‚cyclic logger‘
*
*
*
Stor
Store: logger function ‚individual value logger‘
*
*
*
oFF
no logger function
*
*
*
CYCL
1..3600
Cycle time of cyclic logger [seconds]
*
*
Lo.Po
on/oFF
Low-power logger with very low power consumption
(only for cyclic logger and slow measuring rate)
*
*
SEt
CLOC
Set Clock: Setting Of Real Time Clock
CLOC
HH:MM
Clock: Setting of time hours:minutes
dAtE
TT.MM
Date: Setting of date day.month
YEAr
YYYY
Year: Setting of year
C_log: cyclic logger (active) C_dat: cyclic logger with data (no active logging) C_stor: individual value logger with data
Note: When using the logger function some settings in the menu may not be accessible (*).
If this settings should be changed, the logger has to be stopped before, eventually the logger
data has to be cleared. (p.r.t. chapter 8)
device type
analog output
adjustment of sensor
alarm function
dAC.0 / dAC.1
OFFS
Al.Lo
Al.Hi
GMH 3181-002
-500.0 ... 500.0 Pa
-50.0 ... 50.0 Pa
- 500 Pa ... AL.Hi
AL.Lo ... 500 Pa
GMH 3181-01
-1.00 ... 25.00 mbar
-5.00 ... 5.00 mbar
- 1 mbar ... AL.Hi
AL.Lo ... 25 mbar
GMH 3181-07
-10.0 ... 350.0 mbar
-50.0 ... 50.0 mbar
- 10 mbar ... AL.Hi
AL.Lo ... 350 mbar
GMH 3181-07B
-10.0 ... 420.0 mbar
-50.0 ... 50.0 mbar
- 10 mbar ... AL.Hi
AL.Lo ... 420 mbar
GMH 3181-07H
-1.00 ... 70.00 mbar
-5.00 ... 5.00 mbar
-100 mbar ... AL.Hi
AL.Lo ... 70 mbar
GMH 3181-13
-100 ... 2000 mbar
-500 ... 500 mbar
-100 mbar ... AL.Hi
AL.Lo ... 2000 mbar
GMH 3181-13
Option: MB -1..2 BAR
-1000 ... 2000 mbar
-500 ... 500 mbar
-1000 mbar ... AL.Hi
AL.Lo ... 2000 mbar
GMH 3181-12
0 ... 1300 mbar absolute
-500 ... 500 mbar
0 bar ... AL.Hi
AL.Lo ... 1300 mbar
7 Remarks To Special Features
7.1 Different Kinds Of Measuring: „rAtE-Slo, -P.dEt, -FASt“
Three different kinds of measuring pressure are supported. Two of them are working with high measuring
frequency of more than 1000 measurings per second. If one of them was chosen in the configuration (see
above), this will be displayed in the secondary display: „P.dEt“ or „FASt“.
7.1.1 rAtE-Slo: Standard Measuring
Measuring rate 4Hz, averaging and filter functions are active.
Application: Measuring of slowly changing or static pressures, e.g. measuring of leakproofness,
atmospheric pressure...
Highest accuracy, high noise immunity (EMI and unstable measuring signals), low power consumption.
7.1.2 rAtE-P.dEt: Peak detection
Measuring rate >1000Hz, the value is displayed unfiltered.
Application with logger function: Measuring of short pressure peaks or fast changing pressures with a
resolution of < 1 ms. The cyclic logger function records the arithmetic mean value, the highest and the
lowest peak of the refering time interval.
Attention: higher power consumption, measuring is sensitive to noise (EMI,..).

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 9 of 16
7.1.3 rAtE-FASt: Fast filtered measuring
Measuring rate >1000Hz, the value is filtered slightly (higher noise immunity than P.dEt, small peaks will be
filtered out), apart from that identical behaviour like P.dEt.
7.2 Sea Level Correction (only for GMH 3181-12 )
The device displays the absolute pressure measured at the sensor. This is not necessarily the same like the
values given by weather stations! The weather stations‘ values are giving the pressure at sea level. Usually
the sensor is placed above sea level and therefore, if the value at sea level(zero) is to be measured, the
pressure loss resulting from the actual level above sea level has to be considered! To correct the measuring
display activate the „Sea-Level-Function“ (SL, p.r.t. chapter 6Fehler! Verweisquelle konnte nicht
efunden werden.). Then enter the altitude above sea level of the sensor‘s location in meters (Alti, p.r.t.
chapter 6). When activated, the display shows the SL-arrow and the device displays the pressure value at
sea level.
7.3 Averaging Function
The averaging function concerns the display values (LCD and interface). It is completely independent from
the averaging of the logger function, please don’t mix them up!
The averaging integrates the measuring values during a selectable period of time and then calculates the
average display value. It is independent from the selected kind of measuring (slow, fast, peak detect) .
As long as not enough values are collected (selected averaging time) to calculate a average value, the
upper display shows “----“, the lower display a ‘countdown‘.
During an active low-power-logging procedure the averring is always deactivated
Function of min/max-value memory during averaging:
- If averaging is activated and slow measuring is selected (rAtE-Slo), the min-/max-value memory refers to
the average display value.
- If averaging is activated and fast measuring is selected (rAtE-FASt or P.dEt) , the min-/max-value
memory refers to the internal measured values (fast peaks can be detected).
7.4 Power off Time
If there won’t be pressed any key and no interface communication takes place for the time of the power off
time setting (P.Off), the device will be switched off automatically to save battery power.
If P.oFF = oFF then the automatic switch off is deactivated.
7.5 Alarm
There are three possible settings: Alarm off (AL. oFF), on with horn sound (AL. on), on without horn sound
(AL. no.So).
Following conditions will display an alarm, when the function is activated (on or no.So):
-Value is below lower (AL. Lo) or above upper alarm rail (AL.Hi).
-Sensor error (Sens Erro)
-Low battery (bAt)
-Fe 7: System error (always with sound)
In case of an alarm and when polling the interface the prio-flag is set in the returned interface message.
7.6 Real Time Clock
The real time clock is used for the logger function: Recorded values are also containing the point of time,
when they were measured. Please check the settings when necessary.
If the battery was replaced the referring menu ‚CLOC‘ will automatically be started.

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 10 of 16
8 Operation Of Logger
The device supports two different logger functions:
„Func-Stor“: each time when „store“ (key 6) is pressed a measurement will be recorded.
„Func-CYCL“: measurements will automatically be recorded each interval, which was set in the logger
menu ‚CYCL‘ until the logger will be stopped or the logger memory is full. The recording
is started by pressing „Store“ 2 seconds.
The logger records 3 measurement results each time:
current or mean value (depending on logger setting, see below), min peak and max peak.
Min and max peak are the minimum resp. the maximum of the measured values since the last recording.
Using them allows f.e. analysis of fluctuating pressures.
For the evaluation of the data the software GSOFT3050 has to be used. The software also allows easy
configuration and starting of the logger.
When the logger is activated (Func Stor or Func CYCL) the hold function is no more available, the key 6 is
solely used for the operation of the logger functions.
8.1 „Func-Stor“: Storing Single Measurements
Each time when „store“ (key 6) is pressed a measurement and its time stamp will be recorded.
The recorded data can be viewed either in the display (when calling the configuration an additional menu
„REAd LoGG“ is displayed, see below) or by means of the interface and a PC with GSOFT3050-software.
Max. number of measurings: 99
A measuring contains: - current measuring value at the time of recording
- min peak, max peak since the last recording
- time and date of the recording
After each recording „St. XX“ will be displayed for a short time. XX represents the number of the recording.
If logger memory contains recordings already:
When „Store“ is pressed for 2 seconds, the choice for clearing the logger memory will be displayed:
The selection can be made by (key 2) and (key 5). "Quit" (key 6) enters the choice.
If the logger memory is full, the display will show:
Viewing Recorded Measurings
Within the „LoGG Stor“ function the measurings can be viewed directly in the display not only by means of a
computer (like at „Func CYCL“): press 2 seconds „Set“ (key 4): The first menu displayed now is „rEAd
LoGG“ (read logger data). After pressing (key 3) the measurement recorded last will be displayed,
changing between the different values referring to the measurement also is done by pressing .
Changing the measurement is done by pressing the keys or .
Clear all
recordings
Clear the last
recording
Clear nothing
(cancel menu)

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 11 of 16
8.2 „Func-CYCL“: Automatic Recording With Selectable Logger-Cycle-Time
The Logger-Cycle-Time is setable (p.r.t. Configuration). For example „CYCL“ = 60: A measuring is recorded
after each 60 seconds.
When the slow measurement "rAtE-Slo" is chosen, additionally a low power function is available: „Lo.Po“.
If „Lo.Po“ is on, the device only will take a measurement at the point of time of the recording. In between the
recordings the measuring shut’s down. This decreases the power consumption enormously and therefore is
recommended e.g. for long time recordings where no mains adapter is available.
Max. number of measurings: 10000
Cycle time: 1...3600 seconds (=1h), selectable in the configuration
A measuring contains:
rAtE SLo: - current measuring value at the time of recording
- min peak, max peak since the last recording
rAtE FASt,P.dEt - arithmetic mean value since the last recording
- min peak, max peak since the last recording
Starting a recording:
By pressing "Store" (key 6) for 2 seconds the logger operation will be called. The display will show:
By pressing "Store" again the recording will be initiated.
After that the display shows ‘St.XXXX‘ for a short time whenever a measuring is recorded.
XXXX is the number of the measuring 1..10000.
If the logger memory is full, the display will show: The recording automatically will be stopped.
If Low-Power-Logger-Function „Lo.Po = on“ the device switches itself off as soon as the memory gets filled.
Stopping the recording manually:
By pressing "Store" (key 6) the recording can be stopped manually. Then the following choice appears:
The selection can be made by (key 2) and (key 5). "Quit" (key 6) enters the choice.
Note: If you try to switch off the instrument in the cyclic recording operation you will be asked
once again if the recording is to be stopped.
The device can only be switched off after the recording has been stopped!
The Auto-Power-Off-function is deactivated during recording!
Clear Recordings:
By pressing "Store" (key 6) for 2 seconds the logger operation will be called.
The display will show: By pressing the keys (key 2) or (key 5) the display will change to .
When „Store“ is pressed, the choice for clearing the logger memory will be displayed:
Clear all recordings
Clear the last
recording sequence
Clear nothing
(cancel menu)
The selection can be made by (key 2) and (key 5). "Quit" (key 6) enters the choice.
Stop the
recording
Do not stop the
recording

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 12 of 16
9 Output
The output can be used as serial interface (for USB 3100, USB 3100 N, GRS 3100 or GRS 3105
interface adapters) or as analog output (0-1V).
If none of both is needed, we suggest to switch the output off, because battery life then is extended.
9.1 Serial Interface
By means of the serial interface and a suitable electrically isolated interface adapter (USB 3100, USB 3100
N, GRS 3100 or GRS 3105) the device can be connected to a computer for data transfer.
With the GRS 3105 up to 5 devices of the GMH3xxx- series can be connected to one interface (see also
manual of GRS 3105). As a precondition the base addresses of all devices must not be identical, make sure
to configure the base addresses accordingly (refer menu point “Adr.” in chapter 6).
To avoid transmission errors, there are several security checks implemented e.g. CRC.
The following standard software packages are available:
GSOFT3050: Operation and read out of logger function, data display in diagrams and tables
GMHKonfig: Software for a comfortable editing of the device (e.g. Material selection…)
EBS20M / 60M: 20-/60-channel software to display the measuring values
In case you want to develop your own software we offer a GMH3000-development package including:
a universally applicable Windows functions library ('GMH3000.DLL') with documentation that can be
used by the most programming languages. Suitable for Windows XP™, Windows Vista™, Windows 7™
Programming examples Visual Basic 4.0™, Delphi 1.0™, Testpoint™
In addition to the operation at a PC the device can be operated with the GAM3000-device, to use the alarm
function for simple supervision and controlling applications. Just connect a GAM3000 to the interface,
activate the alarm function of the GMH and the relays output is operating.
The device has 3 channels:
1: current measuring value (base address)
2: min peak (p.r.t. chapter 8)
3: max peak (p.r.t. chapter 8)
Note: The measuring-/ alarm- and display range values read back from the interface are always in
the selected measurement unit (mbar, bar...)!
Supported functions:
Channel
Code
Name/Function
Channel
Code
Name/Function
1
2
3
1
2
3
x
x
x
0
Read measurement value
x
x
x
201
Read max display range
x
x
x
3
Read system state
x
x
x
202
Read display range - unit
x
6
Read min memory
x
x
x
204
Read display range –decimal point
x
7
Read max memory
x
208
Read # of channels
x
x
x
12
Read ID number
x
214
Read scale adjustment [%]
x
22
Read min alarm rail (AL. - AL.Lo)
x
216
Read offset adjustment
x
23
Read max alarm rail (AL. - AL.Hi)
x
220
Read offset adjustment
x
32
Read configuration flag
BitAlarmAn:1; BitAlarmHupe:3;
BitCorrectToSealevel: 32 *; BitPeakDetection:33;
BitFastFiltered:34; BitLoggerAn:50;
BitZyklischerLogger:51; BitStromsparlogger:52
x
221
Read altitude *
x
222
Set altitude *
x
223
Set power off time (Conf-P.oFF)
x
x
x
224
Logger: Read data of CYCL- Logger
x
102
Set min alarm rail (AL. - AL.Lo)
x
225
Logger: Read cycle time (LoGG - CYCL)
x
103
Set max alarm rail (AL. - AL.Hi)
x
226
Logger: set cycle time (LoGG - CYCL)
x
160
Set configuration flag (refer to 32)
x
227
Logger: start recording
x
174
Clear min memory
x
228
Logger: Read # of recordings made
x
175
Clear max memory
x
229
Logger: Read state
x
x
x
176
Read min measuring range
x
231
Logger: Read stop time
x
x
x
177
Read max measuring range
x
233
Read real time clock (CLOC)
x
x
x
178
Read measuring range –measuring unit
x
234
Set real time clock (CLOC)
x
x
x
179
Read measuring range –decimal point
x
236
Read logger memory size
x
x
x
180
Read kind of measuring of sensor
x
240
Reset
x
x
x
199
Read kind of measuring of display
x
254
Program version
x
x
x
200
Read min display range
x
260
Logger: read data of STOR Logger
* only available at GMH 3181-12

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 13 of 16
9.2 Analogue Output –Scaling with DAC.0 and DAC.1
Note: Analogue output can not be used during logger recordings
With the DAC.0 and DAC.1 values the output can be rapidly scaled to your efforts.
Keep in mind not to connect low-resistive loads to the output, otherwise the output value will be wrong and
battery life is decreased. Loads above ca 10kOhm are uncritical.
If the display exceeds the value set by DAC.1, then the device will apply 1V to the output
If the display falls below the value set by DAC.0, then the device will apply 0V to the output
In case of an error (Err.1, Err.2, no sensor, etc.) the device will apply slightly above 1V to the output.
plug wiring:
GND
Attention!
the 3rd contact has to be left floating!
Only stereo plugs are allowed!
+Uout
10 Input Adjustment
10.1 Zero Displacement Sensor ('OFFS')
A zero displacement can be carried out for the measured value:
value displayed = value measured - offset
Standard setting: 'off' = 0.0°, i.e. no zero displacement will be carried out. Together with the scale correction
(see below) this factor is mainly used to compensate for sensor deviations. Input is in the display unit.
10.2 Scale Correction Sensor ('SCAL')
The scale of the measuring can be influenced by this setting (factor is in %):
displayed value = measured value * (1+Scal/100)
Standard setting: 'off' =0.000, i.e. value is not corrected. Together with the zero displacement (see above)
this factor is mainly used to compensate for sensor deviations.
10.3 Calibration Services
Calibration certificates –DKD-certificates –other certificates:
If device should be certificated for its accuracy, it is the best solution to return it to the manufacturer.
Only the manufacturer is capable to do efficient recalibration if necessary to get results of highest accuracy!

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 14 of 16
11 Pressure Connection
2 (or 1) universal pressure connector for 6 x 1 mm (4 mm tube inner diameter) or 8 x 1 mm (6 mm tube inner
diameter ) plastic tubes.
11.1 Device type with absolute pressure (GMH 3181-12)
Connect plastic tube to pressure port.
11.2 Device type with relative pressure
For measurements of overpressure (refer to summary):
Connect plastic tube to pressure port "+".
Port "-" will not be used!
For measurements of underpressure (refer to summary):
Plug the tube to pressure port "-". The measuring range covers then up to max. overpressure range
Note: All values are displayed now as positive values. No minus sign will be shown.
Example: it is possible to measure under pressure down to -25.00 mbar, the display shows then
the value 25.00 (no minus sign).
For measurements of pressure differences:
Connect both plastic tubes to pressure port "+" and "-"; make sure to apply higher pressure to port "+".
Measure ranges:
device type
over- or under pressure
under pressure
GMH 3181-002
- 500.0 … 500.0 Pa
---
GMH 3181-01
- 1.00 … 25.00 mbar
-25.00 … 0.00 mbar
GMH 3181-07
- 10.0 … 350.0 mbar
- 350.0 … 0.0 mbar
GMH 3181-07B
- 10.0 … 420.0 mbar
- 420.0 … 0.0 mbar
GMH 3181-07H
- 1.00 … 70.00 mbar
-70.00 … 0.00 mbar
GMH 3181-13
- 100 … 2000 mbar
- 2000 … 0 mbar
with option: MB -1..2 BAR
- 1000 … 2000 mbar
12 Error And System Messages
Display
Meaning
What to do?
Low battery power, device will only continue
operation for a short period of time
Replace battery
Battery empty
Replace battery
Mains operation without battery: wrong voltage
Check power supply, replace it when
necessary
No display or
confused
characters,
device does
not react on
keypress
Battery empty
Replace battery
Mains operation without battery: wrong voltage
or polarity
Check power supply, replace it when
necessary
System error
Disconnect battery and power supplies,
wait shortly, then reconnect
Device defective
Return to manufacturer for repair
Err.1
Measured value above allowable range
Check: pressure above max. range?
-> measuring value to high
Sensor defective
Return to manufacturer for repair
Err.2
Measured value below allowable range
Check: pressure below min range?
-> measuring value to low
Sensor defective
Return to manufacturer for repair
Err.4
Value is too low to be displayed, tara is set
Check: display below -2000 (tara?)?
Err.9
Measured value far out of allowable range
Check: pressure not within sensor range?
Err.7
System error
Return to manufacturer for repair

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 15 of 16
13 Specification
GMH 3181 - 002
GMH 3181 - 01
GMH 3181 - 07H
GMH 3181 - 07
Measuring ranges: 1)
-500.0 … 500.0 Pa
(-5.000 … 5.000 mbar)
-1.00 … 25.00 mbar
-1.00 … 70.00 mbar
-10.0 … 350.0 mbar
Overload: 2) (max.)
max. 250 hPa (mbar)
max. 100 mbar
max. 1 bar
max. 1 bar
Resolution:
0.1 Pa (0.001 mbar)
1 Pa (0.01 mbar)
0.01 mbar
0.1 mbar
Accuracy: (typ.)
Hysteresis and linearity
±0.3 % FS
±0.3 % FS
±0.1 % FS
±0.2 % FS
(±0.1 % FS 3))
temp. depending 0 - 50 °C
±0.4 % FS
±0.4 % FS
±0.4 % FS
±0.4 % FS
Available units:
mbar, Pa, kPa,
mmHg, PSI, m H
2
O
mbar, bar, Pa, kPa,
mmHg, PSI, m H
2
O
mbar, bar, Pa, kPa,
mmHg, PSI, m H
2
O
mbar, bar, kPa, MPa,
mmHg, PSI, m H
2
O
GMH 3181 - 07B
GMH 3181 - 13
GMH 3181 - 13
Option: MB -1..2 BAR
GMH 3181 - 12
Measuring ranges: 1)
-10.0 … 420.0 mbar
(-7.5 … 315 mmHg)
-100 … 2000 mbar
-1000 … 2000 mbar
0 … 1300 mbar
absolut
Overload: 2) (max.)
max. 1 bar
max. 4 bar
max. 4 bar
max. 4 bar abs.
Resolution:
0.1 mbar (0.1 mmHg)
1 mbar
1 mbar
1 mbar
Accuracy: (typ.)
Hysteresis and linearity
±0.1 % FS
±0.2 % FS
(±0.1 % FS 3))
±0.2 % FS
(±0.1 % FS 3))
±0.2 % FS
(±0.1 % FS 3))
temp. depending 0 - 50 °C
±0.4 % FS
±0.4 % FS
±0.4 % FS
±0.4 % FS
Available units:
mbar, bar, kPa, MPa,
mmHg, PSI, m H
2
O
mbar, bar, kPa, MPa,
mmHg, PSI, m H
2
O
mbar, bar, kPa, MPa,
mmHg, PSI m H
2
O
mbar, bar, kPa, MPa,
mmHg, PSI, m H
2
O
1) underpressure measurement up to the overpressure measuring range suitable (refer chapter 11.2)
2) without destruction or recalibration of sensor being necessary
3) at OPTION „higher sensor accuracy“
Pressure units: selectable
Measuring rate: slow: 4 meas./sec (ConF-Rate = Slow)
fast: >1000 meas./sec (ConF-Rate = FASt and P.dEt)
Nominal temperature: 25°C
Sensor: Piezo-resistive relative pressure sensor integrated in device.
Suitable for air and non-corrosive and non-ionizing gases and liquids.
(Not suitable for water –use air buffering)
Connection: 2 (1) metal pressure ports for connection to 6 x 1 mm (4 mm inner tube Ø) or
8 x 1 mm (6 mm inner tube Ø) tubes at the top of device
Logger: 2 Functions: individual value logger („Func–Stor“) and cyclic logger („Func–CYCL“)
Memory: Stor: 99 data sets
CYCL: 10000 data sets (in max. 64 recording sequences)
Cycle time CYCL: 1...3600 seconds
Display: 2 four digit LCDs (12.4mm high and 7 mm high) for measuring values, and for min/
max memories, hold function, etc. as well as additional functional arrows.
Pushbuttons: 6 membrane keys
Output: 3.5 mm audio plug, stereo
Output function: selectable as serial interface or analog output
Interface: Serial interface (3.5mm jack) can be connected to USB or RS232 interface of a PC
via electrically isolated interface adapter USB3100, USB 3100 N, GRS3100 or
GRS3105 (see accessories).
Analog output: 0 ... 1 Volt, freely scaleable (resolution 12 bit)

H61.0.3X.6C-01 User’s Manual GMH 3181-…page 16 of 16
Power supply: 9V battery, type: IEC 6F22 (included in scope of supply)
as well as additional d.c. connector (diameter of internal pin 1.9 mm) for external
10.5-12V direct voltage supply. (suitable power supply: GNG10/3000)
Power consumption: Slow measuring rate: ~ 0.6 mA
Fast measuring rate: < 2.5 mA
Low-Power-Logger: < 0.1 mA (for cycle time>30s, without interface
communication active and no alarm horn sounding) up to 0.4 mA (at cycle time 1s)
Low battery warning: ' bAt '
Working conditions: -20 ... +50 °C, 0 ... 95 %RH (not condensing)
Storage temperature: -20 ... +70 °C
Housing: impact-resistant ABS, membrane keyboard, transparent panel, Front side IP65
Dimensions: 142 x 71 x 26 mm (L x W x D) + metal pressure ports 11mm at top of device
Weight: approx. 170 g
EMC: The device corresponds to the essential protection ratings established in the
Regulations of the Council for the Approximation of Legislation for the member
countries regarding electromagnetic compatibility (2004/108/EG).
Additional fault: <1%
14 Reshipment and Disposal
14.1 Reshipment
All devices returned to the manufacturer have to be free of any residual of measuring media
and other hazardous substances. Measuring residuals at housing or sensor may be a risk for
persons or environment
Use an adequate transport package for reshipment, especially for fully functional devices.
Please make sure that the device is protected in the package by enough packing materials.
14.2 Disposal instructions
Batteries must not be disposed in the regular domestic waste but at the designated collecting
points.
The device must not be disposed in the unsorted municipal waste! Send the device directly to
us (sufficiently stamped), if it should be disposed. We will dispose the device appropriate and
environmentally sound.
_
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