GREISINGER GMH 3151 User manual

H61.0.02.6C-08
GHM Messtechnik GmbH • Standort Greisinger
Hans-Sachs-Str. 26 • D-93128 Regenstauf
+49 (0) 9402 / 9383-0 +49 (0) 9402 / 9383-33 [email protected]
WEEE-Reg.-Nr. DE 93889386
GMH 31 Series
Druck / Pressure
As of Version 7.4 GMH 3151
Operating manual
Handheld Pressure-Meter
for GMSD, GMXD, MSD und MXD - Pressure Sensors

H61.0.02.6C-08 User’s Manual GMH 3151 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..............................................................................................8
7.2 MEASURING OF WATER LEVEL –DISPLAY UNIT [M] ..............................................................................8
7.3 SEA LEVEL CORRECTION FOR ABSOLUTE PRESSURE SENSORS.............................................................8
7.4 AVERAGING FUNCTION........................................................................................................................9
7.5 POWER OFF TIME................................................................................................................................9
7.6 ALARM ...............................................................................................................................................9
7.7 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 DRIFT OF MEASUREMENTS.............................................................................................................13
10.2 ZERO DISPLACEMENT SENSOR ('OFFS').........................................................................................13
10.3 SCALE CORRECTION SENSOR ('SCAL')...........................................................................................13
10.4 CALIBRATION SERVICES.................................................................................................................13
11 PRESSURE CONNECTION...............................................................................................................13
11.1 ABSOLUTE PRESSURE SENSORS (TYPES:GMSD/GMXD…BA) .......................................................13
11.2 RELATIVE PRESSURE SENSORS (TYPES:GMSD/GMXD…MR, GSMD/GMXD…BR)........................13
11.3 STAINLESS STEEL PRESSURE SENSORS (TYPES:GMSD/GMXD...MRE, GMSD/GMXD...BRE,
GMSD/GMXD...BAE AND MSD/MXD...MRE, MSD/MXD...BRE, MSD/MXD...BAEWITH MSD-K31)...........14
12 ERROR AND SYSTEM MESSAGES.................................................................................................14
13 SPECIFICATION................................................................................................................................15
14 RESHIPMENT, DISPOSAL AND DECOMMISSIONING....................................................................16
14.1 RESHIPMENT.................................................................................................................................16
14.2 DISPOSAL INSTRUCTIONS ...............................................................................................................16
14.3 DECOMMISSIONING........................................................................................................................16

H61.0.02.6C-08 User’s Manual GMH 3151 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.
2 Safety
2.1 Intended Use
This device is designed for the mobile use or the stationary operation in a controlled electromagnetic
environment (lab).
This device must only be used with “GMSD… - K31” or “MSD … ..E” pressure sensors.
Other usages are not intended. Make sure that the measured pressure fits to the measuring range of the
connected sensor.
Personnel which starts up, operates and maintains the device has to have sufficient knowledge of the
measuring procedure and the meaning of the resulting measured values, this manual delivers a valuable
help for this. The instructions of the manual have to be understood, regarded and followed.
To be sure that there´s no risk arising due to misinterpretation of measured values, the operator must have
further knowledge in case of doubt - the user is liable for any harm/damage resulting from misinterpretation
due to insufficient knowledge.
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 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.

H61.0.02.6C-08 User’s Manual GMH 3151 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. Only devices with are specially mark for Ex-protection can be used at potentially explosive
areas. Devices that are not marked for Ex-protection 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
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.
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.
Treat device and sensor carefully. Use only in accordance with above specification. (do not throw, hit
against etc.). Protect plug and socket from soiling.
Connecting/changing sensors
Use only sensors of GMSD ... - K31 or MSD - series!
Other sensors may lead to damage to the device and the sensor.
Switch off device before changing the sensor.
_DANGER
_DANGER
_DANGER
_DANGER

H61.0.02.6C-08 User’s Manual GMH 3151 page 5 of 16
4 Handling
4.1 Display
1
Main display: shows measuring 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
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: Calling of configuration
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

H61.0.02.6C-08 User’s Manual GMH 3151 page 6 of 16
4.3 Connections
Output: Connection for optically isolated interface
adapter or for analog output (please refer to
chapter 9)
Connection for pressure sensors of the GMSD,
GMSD or MSD and MXD-family
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

H61.0.02.6C-08 User’s Manual GMH 3151 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.
Menu
Parameter
Values
Meaning
KEY
Menu
KEY 
KEY or 
SEt
ConF
Set Configuration: Generic Configurations
Unit
mbar,bar..
Unit: Unit of display
*
SL
oFF/on
Sea level correction: on or off
*
Alti
-2000..9999
Altitude above sea level [m] (only if SL )
*
rAtE
Rate: Measuring rate (p.r.t. chapter 7)
*
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 (if Out = SEr)
dAC.0
eg.
-5.00..5.00 mbar
Enter desired value at which the analogue output potential should be 0V
(if Out = dAC)
dAC.1
eg.
-5.00..5.00 mbar
Enter desired value at which the analogue output potential should be 1V
(if Out = dAC)
SEt
Corr
Set Calibration: Adjustment of Sensor
OFFS
Sensordep., e.g.
-5.00..5.00 mbar
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 (=0.0°)
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)
SEt
Set Alarm: Settings Of Alarm Function
AL.
AL.
On
Alarm on, with buzzer sound
no.So
Alarm on, without buzzer sound
oFF
no alarm function
AL.Lo
Sensor-Min...
AL.Hi
Min alarm rail (not when AL. oFF)
Sensor-Min is the lower display range of sensor
AL.Hi
AL.Lo... Sensor-
Max
Max alarm rail (not when AL. oFF)
Sensor-Max is the upper display range of sensor
1 2 3
4 5 6
ON
OFF max
Store
CAL
min
Set
Menu Quit

H61.0.02.6C-08 User’s Manual GMH 3151 page 8 of 16
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: day.month
YEAr
YYYY
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)
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,..).
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 Measuring Of Water Level –Display Unit [m]
When using suitable waterproof pressure sensors the unit [m] for meters of water can be set in the menu
“Unit“. 10m of water are roughly 1 bar over pressure. Measurings can be made e.g. like described below :
With one abs. pressure sensor (SL oFF!): Press ‚Tara‘ when sensor is at ambient air and then bring
sensor to the depth to be measured. The display shows now the depth in [m].
With one rel. pressure sensor: bring tube connection for lower press. in contact to ambient air by means
of a tube (no water contact!) and bring the sensor with its open press. connection for higher pressure to
water depth to be measured (display and is compensated for pressure changes in ambient air).
7.3 Sea Level Correction for Absolute Pressure Sensors
The device displays the absolute pressure. 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 6, setting is only possible, if the abs. pressure sensor is connected
to sensor socket 1). 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.

H61.0.02.6C-08 User’s Manual GMH 3151 page 9 of 16
7.4 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).
7.5 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.
7.6 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.
7.7 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.

H61.0.02.6C-08 User’s Manual GMH 3151 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 following measurement results each time:
current or mean value (depending on logger setting, see below), min peak and max peak of sensor
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.
Please note: When reading out loggerdata either the sensor connected during logging or no sensor should
be connected. Otherwise the measuring unit of the data may be corrupted.
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.
Please note: For the Func-Stor-logging function it is not allowed to change the pressure sensor after values
are stored, otherwise invalid data could be read out.
For the read out of the logger the sensor has to be kept connected!
Max. number of measurings: 99
A measuring contains: - current measuring value at the time of recording
- min peak since the last recording
- 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)

H61.0.02.6C-08 User’s Manual GMH 3151 page 11 of 16
8.2 „Func-CYCL“: Automatic Recording With Selectable Logger-Cycle-Time
The Logger-Cycle-Time is settable (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 shuts 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:
slow measuring rate (rAtE Slo):
- current measuring value at the time of recording
- min peak, max peak since the last recording
fast measuring rates (rAtE FASt,P.dEt):
- arithmetic mean value since the last recording
- min peak, max peak since the last recordingStarting 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

H61.0.02.6C-08 User’s Manual GMH 3151 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…)
EBS 20M / 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™,
Windows 8 / 8.1™, Windows 10™
Programming examples Visual Studio 2010 (C#, C++ and VB), Testpoint™,LabView™ etc.
In addition to the operation at a PC the device can be operated with the GAM 3000 device, to use the alarm
function for simple supervision and controlling applications. Just connect a GAM 3000 to the interface,
activate the alarm function of the GMH and the relays output is operating.
The device has 3 channels:
-Channel 1: current measuring value (base address)
-Channel 2: min peak (p.r.t. chapter 8)
-Channel 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
0
Read measurement value
x
208
Read # of channels
x
x
3
Read system state
x
222
Read power off time (Conf-P.oFF)
x
12
Read ID number
x
223
Set power off time (Conf-P.oFF)
x
22
Read min alarm rail (AL. - AL.Lo)
x
x
224
Logger: Read data of CYCL- Logger
x
23
Read max alarm rail (AL. - AL.Hi)
x
225
Logger: Read cycle time (LoGG - CYCL)
x
32
Read configuration flag
BitAlarmOn: 1, BitAlarmSound:3;
BitLoggerOn:50; BitCyclicLogger:51;
BitLowPowerLogger:52
x
226
Logger: set cycle time (LoGG - CYCL)
x
227
Logger: start recording
x
228
Logger: Read # of recordings made
x
160
Set configuration flag (refer to 32)
x
229
Logger: Read state
x
x
176
Read min measuring range
x
231
Logger: Read stop time
x
x
177
Read max measuring range
x
233
Read real time clock (CLOC)
x
x
178
Read measuring range unit
x
234
Set real time clock (CLOC)
x
x
179
Read measuring range decimal point
x
236
Read logger memory size
x
x
180
Read kind of measuring of sensor
x
237
Read logger filecount
x
238
Read logger filepointer
x
x
199
Read kind of measuring of display
x
239
Read logger file info
x
x
200
Read min display range
x
240
Reset
x
x
201
Read max display range
x
254
Program version
x
x
202
Read display range - unit
x
260
Logger: read data of STOR Logger
x
x
204
Read display range - decimal point
x
x
263
Read logger channel info

H61.0.02.6C-08 User’s Manual GMH 3151 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
10.1Drift of Measurements
The GMH 31 with its according sensors is a highly stable measuring system with extreme low drift. Although
especially in harsh environments the displayed value of the measuring chain „instrument + sensor“ may drift
over time. Depending on the application and need of precision we recommend a regular check.
Deviations can be compensated with zero displacement and scale correction (see below).
At normal use a checking each year is recommended. A system check at the manufacturer is recommended
in case of doubt: see chapter Calibration Services.
10.2Zero 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.
10.3Scale 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.
10.4 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!
11 Pressure Connection
The device is designed to be connected to the sensors of the GMSD/GMXD/MSD/MXD...-series without a
new calibration being necessary. Therefore a great variety of replaceable sensors of e.g. -1.999...2.500
mbar relative up to 0...1000 bar absolute pressure can be connected to the device.
11.1 Absolute Pressure Sensors (types: GMSD/GMXD…BA)
Connect plastic tube with an internal diameter of 4 mm to pressure port "A". (Port "B" is not used.)
11.2 Relative Pressure Sensors (types: GMSD/GMXD…MR, GSMD/GMXD…BR)
For measurements of over- or under pressure:
Connect plastic tube with an internal diameter of 4 mm to pressure port "B". (Port "A" is not used.)

H61.0.02.6C-08 User’s Manual GMH 3151 page 14 of 16
For measurements of under pressure: (with higher negative measuring range)
Connect plastic tube with internal diameter of 4 mm to pressure port "B". Port "A" will not be used!
Pressure sensors GMSD 2,5 MR, GMSD 25 MR and GMSD 350 MR allow for measurements of under
pressure up to the entire over pressure measuring range by re-plugging the tube to pressure port "A".
Please note that all values are displayed as positive values. No minus sign will be shown. (Example for
GMSD 25 MR: For tube connection "B" the measuring range covers -19.99 to 25.00 mbar. If you replug
to port "A" under pressure measurements down to -25.00 mbar could be carried out with the display
showing the value 25.00 (no minus sign).
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 with an internal diameter of 4 mm to pressure port "B" and "A"; make sure to
apply higher pressure to port "B".
11.3 Stainless steel pressure sensors (types: GMSD/GMXD...MRE, GMSD/GMXD...BRE,
GMSD/GMXD...BAE and MSD/MXD...MRE,
MSD/MXD...BRE, MSD/MXD...BAE with MSD-K31)
For measurements of over-, under- or absolute pressure screw sensor to G1/4" pressure terminal or plug
plastic tube to a suitable adapter.
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
or Err.9
No sensor connected
Switch off device and connect sensor
Connected sensor or device defective
If 2nd sensor available, check if device is ok. Return
defective device/sensor to manufacturer for repair
Value extremely out of measuring range
Check: pressure not within sensor range?
No display or
confused
characters,
device does not
react on keypress
Battery empty
Replace battery
Mains operation: 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 not within sensor range?
-> measuring value to high!
Sensor defective
Return to manufacturer for repair
Err.2
Measured value below allowable range
Check: pressure not within sensor range?
-> measuring value to low!
Sensor defective
Return to manufacturer for repair
Err.3
Display range overflow
Check: value above 19999 -> to high to be
displayed
Err.4
Display range underflow
Check: value below -19999 (Tara?) -> to low!
Er.11
Value could not be calculated
Choose different unit
Calculation overflow happened
Choose different unit
Err.7
System error
Return to manufacturer for repair
––––
Sensor not present / recognised
reconnect sensor,
during logging: stop the logger and restart it
could not calculate value
suitable sensor / unit combination necessary

H61.0.02.6C-08 User’s Manual GMH 3151 page 15 of 16
13 Specification
Measuring ranges:
Display range: max. -19999...19999 digit, depending on connected sensor
Resolution: depending on connected sensor
Pressure units: mbar, bar, kPa, MPa, mmHg, PSI, mH2O
selectable depending on connected sensor
Accuracy: (typ.) ±0,1%FS (at nominal temperature)
(FASt and P.dET: ±0.5%FS)
Measuring rate: slow: 4 meas./sec (ConF-Rate = Slow)
fast: >1000 meas./sec (ConF-Rate = FASt and P.dEt)
Nominal temperature: 25°C
Sensor: All sensors of the GMSD and GMXD..-series without recalibration can be
connected
Connection: Mini-DIN-Socket with locking mechanism
The sensor will automatically be detected, the measurement range settings are set
referring to sensor data
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)
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: < 1.6 mA
Fast measuring rate: < 4.5 mA
Low-Power-Logger: < 0.3 mA (for cycle time>30s, without interface
communication active and no alarm horn sounding) up to 0.8 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)
Weight: approx. 150 g
EMC: The instruments confirm to following European Directives:
2014/30/EU EMC Directive
2011/65/EU RoHS
Applied harmonized standards:
EN 61326-1 : 2013 emissions level: class B
emi immunity according to table 3 and A.1
Additional fault: <1%
_
+

H61.0.02.6C-08 User’s Manual GMH 3151 page 16 of 16
14 Reshipment, Disposal and Decommissioning
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.
14.3 Decommissioning
When decommissioning the device, the pressure connections must not be dismounted under pressure.