ME-Messysteme GSV-2LS, GSV-2AS, GSV-2TSD-DI, GSV-2FSD, GSV-2CAN User Manual

Strain Gage Bridge Amplifier GSV-2

User's Manual

GSV-2LS, GSV-2AS, GSV-2FSD

GSV-2CAN, GSV-2TSD-DI

Update 15.03.2016

Table of Contents

Pin Configuration....................................................................................................................4

15 pole terminal block for the sensor connection..............................................................4

5 pole terminal block for RS232 / RS422..........................................................................5

Backplate of the table case (GSV-2TSD-DI).....................................................................5

Side panel GSV-2TSD-DI..................................................................................................6

12-pole terminal block GSV-2TSD....................................................................................6

Connection scheme 12-pole terminal block......................................................................6

15-pole SUB-D connector of the GSV-2TSD (-DI)............................................................7

Connection diagram 15-pole SUB-D connector................................................................8

Connection and start-up.........................................................................................................8

Connecting the sensor.......................................................................................................8

Connecting the serial interface..........................................................................................9

Commissioning devices with CANopen interface............................................................10

3 pole connector plug / socket M8..............................................................................11

Jumper for terminating resistor 120 Ohm...................................................................11

Setting the input sensitivity..............................................................................................11

Null-balance calibration...................................................................................................12

Using switching output.........................................................................................................12

Usage of the keyboard and the menu.................................................................................14

Advice..............................................................................................................................15

Description of the keys....................................................................................................16

Number format.................................................................................................................16

Settings of the measuring value display (scaling factor).................................................16

Using and managing of the user data record assigned text................................................16

1. Basic procedure:.....................................................................................................17

2. Assignment and cancellation of info text- assignment................................................18

RS 232/422 Protocol of the GSV-2 Strain Gage Bridge Amplifier GSV-2 .........................19

Data output......................................................................................................................19

Display settings................................................................................................................20

Output of the register data ..............................................................................................20

Commands to the GSV-2................................................................................................20

Table of commands.........................................................................................................21

Description of the commands..........................................................................................24

CANbus / CANOpen protocol of the GSV-2-CANOpen......................................................56

Connecting the CAN-Bus wires.......................................................................................56

Bus-termination................................................................................................................56

Supported services..........................................................................................................57

Interpretation of the 1st Tx-PDO.....................................................................................57

Send-conditions for the 1st Tx-PDO................................................................................57

Default settings:...............................................................................................................58

General advices and Tips ...................................................................................................58

Technical Data.....................................................................................................................60

CANbus Interface............................................................................................................62

CANOpen Vendor-ID.......................................................................................................62

Resolution........................................................................................................................63

Description of the jumpers / selectors.............................................................................65

Dimensions of the circuit board GSV-2L........................................................................65

Dimensions of the aluminium housing of the GSV-2AS.................................................66

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Dimensions of the GSV-2TSD.........................................................................................67

Front panel cut out and housing of the GSV-2FSD........................................................67

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Pin Configuration

15 pole terminal block for the sensor connection

Figure 1: Terminal block 15pole and 5 pole in GSV-2LS, GSV-2AS, GSV-2ASD and GSV-2FSD

Pin Name Description Tip

1 GNDB Supply ground Connection for cable shield
2 +Us Positive bridge sensor supply
3 +UF Positive sens for 6-wire technology
4 +UD Positive differential input
5 -UD Negative differential input
6 -UF Negative sens for 6-wire technology
7 -Us Negative bridge sensor supply

The signals at terminals 2..7 are
acquired by software. Connection of
sensors in 4- or 6-wire technology.
Bridging between +Us and +UF as
well as between -US and -UF are not
necessary.

8 UE Analogue Input 0..10V
9 UA Analogue Output ±5 V / option. 4...20mA

10 GNDA Ground analogue In/Output

Analogue input between UE and
GNDA. Analogue output between UA
and GNDA

11 SW1 ² Threshold output No. 1

Open Collector (Open Emitter alternatively),
galvanically isolated

12 Tara

1

Tare input

Affects digital serial and analogue output

13 SW2 2Threshold output No. 2 See Tip for SW1
14 UB Supply voltage 12..24 VDC
15 GNDB Supply ground

Connection for supply voltage

Table 1: 15pole terminal block in GSV-2LS, GSV-2AS, GSV-2ASD and GSV-2FSD

1 In case of voltages above 3.4 V at this terminal, a tare adjustment is initiated. Offset adjustment is then done in the analog part of

the GSV. In addition the digital output is also set to zero.

2 Threshold values are programmed via the RS 232 port.

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5 pole terminal block for RS232 / RS422

Pin Standard CAN/CANopen Description

A GNDC GNDC Ground RS232 / RS422 Interface
B RX / RX- Rx Data connection Rx for RS232 / Rx- for RS422
C TX / TX- Tx Data connection Tx for RS232 / Tx- for RS422
D RX+ CAN_GND Rx+ for RS422 Ground CAN bus
E TX+ CAN_L Tx+ for RS422 CAN low

F n.a. CAN_H n.c. CAN high

Backplate of the table case (GSV-2TSD-DI)

Figure 2: Backplate GSV-2TSD (-DI)

M8 plug connector for GSV-2TSD-DI CANopen

In the version with CANopen Interface there are two additional M8 male / female
connectors on the backplate.

Pin Funktion Wire colour

1 CAN-H brown
3 CAN-L blue
4 GND black

the CAN-Interface is galvanically isolated.

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Side panel GSV-2TSD-DI

Five 2mm plugs are arranged at the side panel. Two isolated threshold outputs and one
input for the tare / set zero functioa are available.

black Set zero input Input voltage 9 .. 30 Volts
green Threshold 1 CMOS relay outputs,

isolated, 60 VDC, 40 VAC

yellow Threshold 2 CMOS relay outputs,

isolated, 60 VDC, 40 VAC

12-pole terminal block GSV-2TSD

Pin Name Description Tip

1 Shielding Shield and GNDB Connect the cable shield here
2 +Us Positive bridge sensor supply
3 +UF Positive sens for 6-wire technology
4 +UD Positive differential input
5 -UD Negative differential input
6 -UF Negative sens for 6-wire technology
7 -Us Negative bridge sensor supply (GND)

The signals at terminals 2..7 are
acquired by software. Connection of
sensors in 4- or 6-wire technology.
Bridging between +Us and +UF as
well as between -US and -UF are not
necessary.

8 -UD2 Negative differential input 2
9 HB Completion for halfbridge

To connect half- and quarterbridges, terminal
8 and 9 must be connected together. See
connection scheme on p.5.

10 QB120 Completion quarterbridge 120 Ohms
11 QB350 Completion quarterbridge 350 Ohms
12 QB1000 Completion quarterbridge 1000 Ohms

For connection of quarterbridge, 120,
350 or 1000 Ohms.

Table 2: Connection of 12-pole terminal block GSV-2TSD (-DI)

Connection scheme 12-pole terminal block

Figure 3: Connection of Full-, Half- and Quarterbridge sensors to the 12-pole terminal block

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15-pole SUB-D connector of the GSV-2TSD (-DI)

Pin Name Description

1 Shielding Cable shield
2 GNDA Analogue input ground
7 Tare Tare input / Trigger input
9 UE Analogue input

10 UA Analogue output

6 +Us Positive bridge sensor supply
5 -Us Negative bridge sensor supply

8 +UD Positive differential input
15 -UD Negative differential input
13 +UF Positive sens for 6-wire technology
12 -UF Negative sens for 6-wire technology
14 HB Completion for halfbridge
11 QB120 Completion quarterbridge 120 Ohms

3 QB350 Completion quarterbridge 350 Ohms

4 QB1000 Completion quarterbridge 1000 Ohms

To connect half- and
quarterbridges, pin 14
and pin 15 must be
connected together.
Quarterbridges are
connected in 3-wire
technology at pins 5, 8
and QB (3, 11 or 4).

Table 4: Connection of SUB-D 15 plug

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Connection diagram 15-pole SUB-D connector

Table 5: Connection of Full-, Half- and Quarterbridge sensors to the 15-pole SUB-D connector

All ground connections are individually protected by interference suppressor inductors in the GSV. Terminals
GNDB are connected to the housing via interference suppression inductor. Currents above 1A between the
terminals and the housing result in damage to the interference suppression inductor. Before connecting,
please check whether housing, supply ground, the ground of your data acquisition system and your port are
at the same potential.

Connection and start-up

Connecting the sensor

A strain gage full bridge or a load cell is connected to the amplifier's terminal block as
shown below:

4- Wire technology 6-Wire technology1):

Sensor supply + Clip 2 Sensor supply + Clip 2
Sensor supply - Clip 7 Sensor supply - Clip 7
Sensor signal + Clip 4 Sensor signal + Clip 4
Sensor signal - Clip 5 Sensor signal - Clip 5

Sense wire + Clip 3
Sense wire - Clip 6

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All cable shields should be connected to the metal of the cable entrance or to GND.
The supply voltage must be connected to the clips 14 (+) and 15 (GND) of the GSV-2LS,

GSV-2AS, GSV-2ASD and the GSV-2FSD
The analogue output transmits a signal which is proportional to the measured force. We

offer the GSV-2 with the following options: ±5 V, 0...10 V, or 4...20 mA current output. The
output signal is present at the clips 9 and10 (Ground).

The sensitivity of the amplifier can be changed by removing the Jumper „JP1“ from 2
mV/V) to 1 mV/V. The jumper „JP1“ is located on the circuit board, For more detailed
information have a look at page 62.

Connecting the clips 12 and 13 triggers a zero-point adjustment at the analog and digital
outputs. The analog output delivers a voltage from 0 V or a current of 4mA. The system is
then ready for measurements.

1) At the analog output the benefits of the 6-conductor technology are not supported.

Connecting the serial interface

If an RS 232 or RS422 port is used, the following connections should be set up to the PC:

GSV-Clip Cable type 9-pol. Sub-D-Pin (PC-side)

A GND Interface ground GND 5
B RX(-) Data wire TX 3
C TX(-) Data wire RX 2
D (RS 422 only) TX+ Data wire TX+
E (RS 422 only) RX+ Data wire RX+

The data cables RX and TX between the amplifier and the PC are crossed at the SUB-D
connector of the GSV-2TSD.

The measuring values will be displayed on the PC while starting the supplied configuration
programm.
The measuring amplifier GSV-2TSD-DI needs a fully-connected null modem cable, which
means crossing of RxD with TxD, RTS with CTS, and DCD+DSR with DTR also GND with
GND (2 with 3, 7 with 8, 1+6 with 4 as well as 5 with 5).

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Commissioning devices with CANopen interface

For devices with CANopen interface the changing of settings via USB port or via RS232
interface is blocked. These settings via USB or RS232 will be however possible only with
the switch off of the CANopen interface.
To ensure the sonformity with the CANopen protocol, the CANopen interface must be
switched on in the factory state.
The switch off of the CANopen interface is possible with the program “GSV-Term”.
You can find the corresponding point to switch-off the CANbus under this path: "2" (for the
second side) --> "b" (for baud rate / CAN) --> "c" (for CANbus) --> "1" (for switch on/off).
Please note the instructions ba-GSV2CanOpen.pdf.

3 pole connector plug / socket M8

Connector plug and socket are 1:1 connected.

Pin Funktion GSV-3CAN Wire colour

1 Transmit Data TxD / CAN_H 13 brown

3 Receive Date RxD / CAN_L 12 blue
4 GND 11 black

Jumper for terminating resistor 120 Ohm

The fotos show the position for the jumper. For closed jumper the terminating resistor of
120 Ohm is activated.

Jumper for terminating resistor at GSV-2AS Jumper for terminating resistor at GSV-2TSD-DI

Setting the input sensitivity

In the default configuration, the measurement amplifier's input sensitivity is ±2 mV/V.
At this input sensitivity the measurement amplifier works with a bridge excitation voltage of

2.5V.
For specific applications it may be necessary to adjust the measurement amplifier's input
sensitivity.

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1

4

3

a) Enlargement of the input sensitivity and thus the measurement range to 3-5 mV/V,
e.g. for using sensors with an output signal of 3.0 mV/V (mV output voltage per volt bridge

excitation voltage).
b) Reduction of the input sensitivity to 1 mV/V with a bridge excitation voltage of 5.0 V,
e.g. if an especially high resolution is to be achieved.
a) The enlargement of the measurement range from 2.0 mV/V to 3.5 mV/V can be

performed with the help of the gsvterm.exe configuration software. Further information is
to be found in ba-gsvterm.pdf, the instruction manual.
b) The bridge excitation voltage can be converted from 2.5V to 5.0V by relocating a
jumper. Jumper JP1 must be relocated in position 1 for 5.0 V (page 13, GSV-2 circuit

board).
The input sensitivity is reduced to 1 mV/V with this mesure. Jumper JP1 is located in

position 2 in the original delivery status.
Please note: after a change in the bridge excitaion voltage, an automatic calibration must
be triggered with the GSVControl software. Further instructions are to be found in ba­gsvcontrol.pdf, the instruction manual for the software.
A sensor with a specific value of 1 mV/V supplies an anlogue output signal of 5 V or 10 V.

or 20 mA in position 1 at nominal load, depending on the option ordered.
A sensor with a specific value of 2 mV/V then supplies 100% of the output signal at half

the nominal load.

Null-balance calibration

The amplifier's calibration range is ±120% of the measurement range which means that
unsymmetric measuring bridges can also be calibrated.
The GSV-2's operating system performs a null-balance calibration if a level of over 3.4 V
is present at input T relative to GND. It is permissible to connect input T with the
operating voltage of 12V or 24V to perform a null-balance calibration. This voltage must

be present for at least 8 ms to trigger the calibration.
A voltage level at input T triggers a combination of an offset calibration and a

compensation of the digital output value to 0 in devices with a serial interface. The offset
calibration can be triggered and the output value set to 0 separately via the serial

interface.
The null-balance calibration lasts approx. 0.12 s for devices with a 250 Hz analogue filter

and a set transmission rate f of 10Hz.
During the calibration, there is no valid signal at the analogue output. Serial data
transmission and control of the thresholds is deactivated for the duration of the calibration.
Please note: if the so-called Logger Mode is activated via the configuration software, no
null-balance calibration is performed with a high level at input T. A measurement value is

sent via the serial interface instead.

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Using switching output

The GSV-2 has two opto-decoupled, digital outputs (terminals 11 and 13).
In the standard version, these outputs are configured as OpenCollector outputs.
The coil of a relay can be switched between output SW1 or SW2 and supply
voltage UB.
The relay is activated if the threshold is exceeded. The level at SW1 or SW2
then changes from High to Low.

By changing resistances on the circuit board, SW1 and SW2 can also be used
as OpenEmitter outputs. The logic is inverted compared to configuration with an
OpenCollector output.
The switching thresholds are calibrated via the serial interface.
The switching outputs can be configured via software either as a threshold
switch or as a window comparer.
The hysteresis of the threshold switch can be adjusted by assigning the switch­on and switch-off thresholds their own values.
The switch-on threshold must be assigned a larger value than the switch-off
threshold.

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Usage of the keyboard and the menu

Menu entry level

1

Menu entry level 2 Menu entry level 3

Sensor config. ➔unit

➔Sensor capacity

➔Rated output

Select the unit

1

Setting the physical nominal value of the
sensor.

2

Setting the electrical rated output of the sensor.²

Strain analysis ➔Set gage factor

➔Set bridge type

➔Setting the gage factor between 0,2 and 258

3

➔Full bridge: Full bridge circuit with 4 single

strain gauges, all in longitudinal direction.³

➔Half bridge: Half bridge circuit with 2 single

strain gauges, both in longitudinal direction.³

➔Quarter bridge: Quarter bridge circuit with

one single starin gauge.³

➔PR.full bridge: Full bridge circuit with 4 single

strain gauges, 2 in longitudinal and 2 in lateral
direction.³

➔PR.half bridge: Half bridge circuit with 2

single strain gauges, 1 in longitudinal and 1 in
lateral direction ³

Menu entry level 4

Set Poissons ratio (only if PRfull or PR.half
bridge was selected in level 3). Number value
from 0 to 0,5.³

Load settings

➔Default: Factory

settings, i.e. restoring
the GSV-2 parameters
of the initial delivery
state.

➔User 1: User

configurable parameter
record No.1, i.e. loading
values that were
previously saved in
“User 1” with Save
settings.

➔...and so on, to
➔User 6 like 1, but

record No 6

Save settings Storing the actual

parameter configuration in
User 1 to User 6

1 Changing the unit doesn't change the measuring value's scaling!
2 Changing the sensor capacity or the rated output changes the measuring value's scaling.
3 Changing the starin gauge parameters of the strain analysis changes the measuring value's scaling and

the unit.

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Menu entry level

1

Menu entry level 2 Menu entry level 3

Scaling Number value between 0,15

and1580000

Data acquisition

➔Data frequency

➔Data period

Number value for measuring values per second
[Hz]
Number value for data period in seconds

Options ➔Set channel

➔Set threshold

➔Offset value

➔Language²
➔CAN settings

2

Number value 0 or 1

➔on-threshold 1 / 2 Number value of the on-

threshold No. 1 or 2

➔off-threshold 1 / 2 Number value of the off-

threshold No. 1 or 2

➔ Number value that will be added to every

measuring value

➔German or English
➔CAN Node-ID
➔CAN-Baudrate
➔CAN on/off

– By pressing the Menu-key the upper menu level will be re-entered.
– By pressing the OK-key an input will be confirmed or the next menu level will be

entered.

– If any setting is selected, the message “OK to confirm” appears, which can be

confirmed with the OK key or cancelled with MENU.

Advice

• The symbol on the right side of the display means that this setting is enabled.

• The entry into the menu is blocked if a communication via the serial interface is

active (if megsv.dll is used). In this case the display shows “Menu blocked”.

2 Only if CAN-Bus available.

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Description of the keys

Key Function

MODE Switch on and off or enter the logger-menu
MENU

(LEFT)

Enter into main menu or cancel an input.
Move to upper menu level.

If changing number: Move cursor left
UP Browsing the menu entries or augment a number / digit value.
DOWN Browsing the menu entry or reduce a number / digit value.
OK

(RIGHT)

Confirm an input or change into a sub menu.

If changing number: Move cursor right.
SHORT Connecting the inputs +Ud and -Ud (Short-circuit the sensor signal)
ZERO Triggering an automatic zero-adjustment

Number format

To set the number value and the date or the time move with a short press of OK the
cursor to the right and with MENU the cursor to the left. The number above the cursor is
blinking and can be increased or reduced with UP / DOWN buttons.

In order for the setting to take effect, the OK button must be kept pressing until the

whole number flashes.

Then release the OK button, it appears “OK to set”. Confirm this with pressing on OK. To
cancel the time setting press the MENU button long time.

Settings of the measuring value display (scaling factor)

scaling factor = Input sensitivity / Nominal excitation * Nominal load

Input sensitivity of the measuring amplifier

e.g. 3,5 mV/V

Measuring range of the sensor

20 kN

Nominal excitation of the sensor

1,9998 mV/V at 20 kN

This example results in an scaling factor of 35,004.

RS 232/422 Protocol of the GSV-2 Strain Gage Bridge Amplifier GSV-2

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Data output

By default setting, the GSV operates with a communication bit rate of 38400 Baud3,
1 Start bit, 8 data bits, no Parity and 1 stop bit (8N1).

There are two types of data frames for the communication of the measuring values:

1. Binary format

2. Text format
The settings of the data formats may be changed with the software GSV Control.

In the normal mode, the GSV transmits its measuring values to the serial interface
permanently. In the binary format the GSV transmits 5 bytes for every single measuring
value (frame size is 5 Bytes):

, (ASCII: 44d)

Status Hbyte (MSB) MByte Lbyte (LSB)

The first byte is used for synchronization.
From Firmware-Version 1.3.06 on, the status-byte contains in bits 3 and 4 information
about the state of the threshold switches SW1 and SW2.

Bit 7 Bit 6 Bit 5 Bit 4 Bit3 Bit 2 Bit 1 Bit 0
Res. Res. Res. SW 1 SW 2 Res. Res. Res.

Res.: reserved
SW1, SW2: State of the threshold switches SW1 and SW2
1: threshold switch is on, 0: threshold switch is off

After that there are the three data bytes, starting with the-most significant byte (MSByte),
followed by the Mbyte, until the least significant byte, so that 24 Bits are transmitted. In the
unipolar mode the measuring value zero is equal the data value zero (0x000000). In the
bipolar mode the measuring value zero corresponds to the data value 0x800000 as a
hexadecimal value.
At an amplification of 1 mV/V you will get the following raw data:

Measuring value
(hexadecimal)

Unipolar Bipolar

00 00 00 0,0 mV/V -1,05 mV/V
80 00 00 0,525 mV/V 0,0 mV/V
FF FF FF 1,05 mV/V 1,05 mV/V

If another amplification is used, it is necessary to multiply it with the corresponding factor
of proportionality.
The full range of 1,05 mV/V was chosen to be able to measure measuring values which
are a bit greater than 1,0 mV/V. See also p.55

If desired, you can switch the data output to the ASCII Format using the configuration
program GSV.EXE or with the Windows-DLL (or with the firmware-command Set Mode,
38d) . The ASCII output corresponds to the values displayed in the LCD and it also can be
shown with a terminal program.
In the default settings the data format of the ASCII frame is:

3 1) The baud rate can be changed , SetBaud Page 38

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sign, 6 numbers, decimal point, free space, unit, CR, LF
for example

+1.2345 kgCRLF

Attention: If the unit is switched off (with the command number 15, Set unit, code 7), the
output frame ends with „space“ and CRLF: +1.2345 CRLF

Display settings

With the binary coded data protocol the measured values are transmitted standardized to
+ 1.
The values sown in the LC display and in the program are a result of the scaling factor
multiplied by the measured value. This scaling factor can be set by the command “Set
Norm“ or with the configuration program.
This is the formula to calculate the scaling factor :

scaling factor = input sensitivity / rated output * normal load.

Example:

normal load of the load cell: 100kg
rated output of the load cell: 2 mV/V
Input sensitivity of the strain gage amplifier: 2 mV/V
==> scaling factor = 100

Output of the register data

After requesting the data, the answer frame sent begins with a semicolon as a prefix.
From 2 up to 8 data bytes are getting transmitted in the frame depending on the size of
the register. You receive the following format:

for 3 Bytes:

; (ASCII: 59d)

HByte MByte LByte

for 2 Bytes:

; (ASCII: 59d)

HByte LByte

Commands to the GSV-2

Commands to the GSV have the following format:

Command
number

P1 P2 P3 P4

The Command number may be followed by up to four parameters P1…P4, depending on
the command (see the commands description below).

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Table of commands

Note: the command number must be sent as Byte to GSV-2, followed by parameter-bytes.
( the command consist of 1 byte, followed by parameter-bytes).

Command

No.

Command

No.

(Hexadecimal)

Command name Number of

parameters

Number of data

bytes send by the

GSV

0 0 reset status 0 0
1 1 read scale 0 3
2 2 read zero 0 3
3 3 read control 0 3
4 4 read offset 0 2
5 5 write scale 3 0
6 6 write zero 3 0
7 7 write control 3 0
8 8 write offset 2 0

9 9 get all 1 0
10 A save all 1 0
11 B set cal 0 0
12 C set zero 0 0
13 D set scale 0 0
14 E set offset 0 0
15 F set unit 1 0
16 10 set norm 3 0
17 11 set dpoint 1 0
18 12 set frequency 2 0
19 13 set gain 1 0
20 14 set bipolar 0 0
21 15 set unipolar 0 0
22 16

Read frequency

0 3
23 17 Manufacturer setting
24 18 Manufacturer setting
25 19 Manufacturer setting
26 1A get norm 0 3
27 1B get unit 0 1
28 1C get dpoint 0 1
29 1D switch 1 0
30 1E Manufacturer setting
31 1F get serial number 0 8
32 20 set threshold1 4 0
33 21 get threshold1 0 4
34 22 set channel 1 0
35 23 stop transmission 0 0
36 24 start transmission 0 0
37 25 clear buffer 0 0
38 26 set mode 1 0
39 27 get mode 0 1
40 28 Manufacturer setting
41 29 get equipment 0 1
42 2A Manufacturer setting
43 2B firmware version 0 2
44 2C set gauge factor 2 0
45 2D get gauge factor 0 2
46 2E set poisson 1 0
47 2F get poisson 0 1
48 30 set bridge type 1 0
49 31 get bridge type 0 1
50 32 Set Range

1 0

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Command

No.

Command

No.

(Hexadecimal)

Command name Number of

parameters

Number of data

bytes send by the

GSV

51 33 get range 0 1
52 34 reserved
53 35 get offset wait 0 1
54 36 get options 0 3
55 37 reserved
56 38 reserved
57 39 reserved
58 3A reserved
59 3B get value 0 5

4

60 3C clear maximum value 0 0
61 3D set Digits 1 0
62 3E get Digits 0 1
63 3F reserved
64 40 reserved
65 41 Get Channel 0 1
66 42 Get Last Error 0 1
67 43 Set Second Threshold 4 0
68 44 Get Second Threshold 0 4
69 45 Get Device Type 0 1
70 46 calc norm 0 0

128 80 Set TX mode 1 0
129 81 Get TXmode 0 1
130 82 Set Baud

5

1 0

131 83 Get Baud 0 1
132 84

reserved

133 85

reserved

134 86

Set Slow Rate 2

0

135 87

Get Slow Rate 0

2
136 88 Set Special Mode 2 0
137 89 Get Special Mode 0 2
138 8A Write Sampling Rate 3 0
139 8B Read Sampling Rate 0 3
140

8C Set CAN setting 3

0
141

8D Get CAN setting 1

2
142

8E reserved

143

8F reserved
144 90 Set Analogue Filter 2 0
145 91 Get Analogue Filter 0 2
146 92 Switch Blocking 3 0
147 93 Get Command Available 2 1
148 94 Set Noise-Cut Threshold

6

3 0
149 95 Get Noise-Cut Threshold 6 0 3
150 96 Set Auto-Zero Counter 6 2 0
151 97 Get Auto-Zero Counter

1

0 2
152 98 Set User-Text Char 1) 2 0
153 99

reserved

154 9A Set User Offset Value

3

3 0
155 9B Get User Offset Value³ 0 3
156 9C

reserved

4 At a normal version with binary output
5 This command can only be executed with the configuration jumper set, see p.62
6 If function exists (see command description)
1 If funktion existent (s. command description)
3 Existent from firmware-version 1.3 on

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Command

No.

Command

No.

(Hexadecimal)

Command name Number of

parameters

Number of data

bytes send by the

GSV

157 9D

reserved

158 9E SetAdaptFilterMask³ 3 0
159 9F GetAdaptFilterMask³ 0 3
160 A0 SetAdaptFilterOptimize³ 2 0
161 A1 GetAdaptFilterOptimize³ 0 2
162 A2 Read Ranges

7

1 4
163 A3 reserved
164 A4 Get Sensor Capacity

8

0 4
165 A5 Set Sensor Capacity 10 4 0
166 A6 Get Rated Output 10 0 4
167 A7 Set Rated Output 10 4 0

7 From firmware version 1.3.07 on
8 From firmware version 1.5.06 on

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Description of the commands

Comment: For most of the commands described in this chapter there are public dll

functions with almost the same name within a Windows-DLL named megsv.dll (they are
described in the programming manual). Below there are useful tips to understand the
direct RS 232-commands.

reset status

Command number: 0
number of parameters: 0
Bytes sent by the GSV: 0

Reset status: resets the amplifier status and the error code (status=0).
Possible error codes: 0x00

read scale

Command number: 1
Number of parameters: 0
Bytes sent by the GSV: 3

Read scale determines the content of the scale-registers of the GSV. You can save the
value read on your PC and you can restore it with write scale.
Possible error codes: 0xA0, 0x91

Read zero

Command number: 2
number of parameters: 0
Bytes sent by the GSV: 3

Read zero determines the content of the zero-registers of the GSV. You can safe the
value read on your PC and restore it with write zero
possible error codes: 0xA0, 0x91

Read control

Command number: 3
number of the parameters: 0
Bytes sent by the GSV: 3

Read control determines some of the current configuration settings of the GSV. The
bytes returned consists of coded channel, data rate, kind of operation, polarity as well as
amplification of the AD-converter. The received value can be send back with write control.
Possible error codes: 0xA0, 0x91

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Read offset

Command number: 4
number of parameters: 0
Bytes sent by the GSV: 2

Read offset determines the offset setting of the analog front end of the amplifier . The
value received can be send back with write offset .
Possible error codes: 0xA0, 0x91

Write scale

Command number: 5
number of parameters: 3
Bytes sent by the GSV: 0

Write scale sets the input sensitivity of the AD converter. The 3 bytes sent should contain
a value which was recently determined with read scale.

Affected register: Scale.
Value Range: 0x20.00.00..0xFF.FF.FF
possible error codes: 0xA0, 0x55,0x71

Write zero

Command number 6
number of parameters: 3
Bytes sent by the GSV: 0

Write zero sets the zero adjustment of the AD converter. The 3 bytes sent should contain
a value which was recently determined with read zero.

Affected register: Zero.
Value range: 0x00.00.00..0xFF.FF.FF
possible error codes: 0xA0,0x71

Write control

Command number: 7
Number of parameters: 3
Bytes sent by the GSV: 0

Write control resets the configuration which was determined with read control before.
The type of operation, polarity, amplification and Notch-frequency (data frequency) are
set.

Affected register: Channel, frequency, gain, polarity.
Value Range: 0x00.00.00..0xFE.76.FF
possible error codes: 0xA0,0x53,0x54,0x58,0x71

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write offset

Command number: 8
Number of parameters: 2
Bytes sent by the GSV: 0

Write offset sets the Offset configuration of the preamplifier. The bytes sent should
contain a value which was recently determined with read offset.

Remarks: Only the commands write offset and set offset affect the analog output.

Affected register: Offset.

Value Range: 0x00.00..0x0F.FF
possible error codes: 0xA0,0x54,0x71

Get all

Command number: 9
Number of parameters: 1
Bytes sent by the GSV: 0

Get all restores a set of configuration, (some might be stored previously with Save All),
chosen by the parameter:

0: : Restore Setting before the last power on cycle.
1: : Restore Manufacturer Settings

2...7 : Restore configurations saved at dataset 1...6

Affected registers: channel, gain, frequency, offset, zero, scale, threshold.
Value Range: 0x00..0x07
possible error codes: 0xA1,0x54,0x80,0x71

Save all

Command number: 10
Number of parameters: 1
Bytes sent by the GSV: 0

Save all saves all relevant registers of the GSV to a configuration set in an internal
memory. This data remains even when the device is turned off. It is possible to save
different configuration sets. After turning on the amplifier up to 64 memory procedures are
possible. The parameter indicates the number of the configuration set in the memory.

Parameters= 2 to 7: : configuration set 1 to 6, saved by the user.
The positions 0 and 1 can not be programmed by the user. On the position 0 the current
configuration of the GSV is automatically saved.
You can restore the configuration set with get all.
Value Range: 0x02..0x07
Possible error codes: 0xA0,0x54,0x55,0x74,0x71

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Set cal

Command number: 11
Number of parameters: 0
Bytes sent by the GSV: 0

Set cal accomplishes an internal sensitivity calibration of the AD converter. After this
calibration you are operating with the amplification selected by set gain.

Attention: The previous content of the ADCs calibration register is getting lost. The
analog output is not affected.

Remark: After sending this command, the GSV is not sending data for a small period of
time.
Affected registers: Scale.
Possible error codes: 0xA0,0x82

Set zero

Command number: 12
Number of parameters: 0
Bytes sent by the GSV: 0

Set zero accomplishes a zero point adjustment of the connected sensor. The analog
output is not affected.

Remark: After sending this command the GSV is not sending data for a small period of
time. For this purpose all data loggers have to be deleted. If Log- and maximum value
mode (have a look at set mode) is active, the latest maximum value is transmitted once.

Affected register: Zero.
Possible error codes: 0xA0

Set scale

Command number: 13
Number of parameters: 0
Number of parameters: 0

Set scale accomplishes an full sensitivity calibration of the AD converter. In contrast to
set cal, the sensitivity of the entire system including the connected sensor is getting

updated. After a zero point adjustment with set zero this operation is able to calibrate the
amplifier to the full load of the sensor, so the sensor must be loaded with its nominal load,
while executing Set Scale. This command has no affect on the analog output.

Attention: Don't accomplish Set scale (with a normal load) if no zero point calibration
with set zero (without load) was done before.

Remark: After sending this command the GSV is not sending data for a small period of
time. For this purpose all data loggers have to be deleted.

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Affected register: Scale.
Possible error codes: 0xA0,0x81,0x83,0x71

Set offset

Command number: 14
Number of parameters: 0
Bytes sent by the GSV: 0

Set offset accomplishes an offset adjustment of the input stage of the GSV. In contrast to
set zero, this adjustment does affect the analog output of the GSV.

Remark:

While adjusting the GSV is not sending any values.

The time needed to accomplish offset adjustment can be read with get offset wait or you
may get it from the description of the technical data (below) as well.

Affected register: Offset.
Possible error codes: 0xA0,0x83

Set unit

Command number: 15
Number of parameters: 1
Bytes sent by the GSV: 0

Set unit sets the desired unit shown on the LC-display and the ASCII measuring value
frame. Changing the unit hasn't any influence on the scaling, i.e. the scaling has

eventually to be adapted manually.

0: mV/V 22: oztr
1: kg 23: dwt
2: g 24: kNm
3: N 25: %
4: cN 26: 0/00
5: V 27: W
6: µm/m 28: kW
7: (keine) 29: rpm
8: t 30: bar
9: kN 31: Pa
10: lb 32: hPa
11: oz 33: MPa
12: kp 34: N/mm²
13: lbf 35: °
14: pdl 36: Hz
15: mm 37: m/s
16: m 38: km/h
17: cNm 39: m³/h
18: Nm 40: mA
19: °C 41: A
20: °F 42: m/s²
21: K

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Value range: 0x00..0x2A

Possible error code: 0xA0,0x54,0x71

Set norm

Command number: 16
Number of parameters: 3
Bytes sent by the GSV: 0

Set norm sets the scaling factor for the measuring values shown in the LC display, see
chapter “Display settings” before. The decimal point has to be set separately with Set

dpoint.

To calculate the parameter value for set norm the intermediate value dp for the decimal
point has to be calculated first. To do so, the logarithm to the base of 10 of the desired
scaling factor has to get calculated and rounded off to an integer value.

Then the desired scaling factor is divided by 10 to the power of dp.
If the result is greater than 1,6666/1,05 then it has to get divided by 10 again.
And you have to add 1 to the dp value.

The value calculated by this method is multiplied by 5250020 and then rounded to the
next integer value. This value will be transmitted to the GSV in the order High byte (MSB),
Mid byte, Low byte (LSB).
Value Range: 0x10.05.94..0x7F.26.E8
Possible error codes 0xA0,0x54,0x55,0x71

Set dpoint

Command number: 17
Number of parameters: 1
Bytes sent by the GSV: 0

Set dpoint sets the decimal point in the LC-Display to its desired position. To calculate the
parameter value on the basis of a desired scaling factor the calculated value of dp from
the formula for set norm (described there) is used, increased by one. That parameter
value is only accepted within its nominal range from 1 to <n umber of digits>, which means
it cannot be greater than the number of digits displayed in the LC display, see Set/Get
digits below.
Absolute Value Range: 0x01..0x08
Possible error codes 0xA0,0x55,0x56,0x71

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Set frequency

Command number: 18
Number of parameters: 2
Bytes sent by the GSV: 0

With Set frequency the measuring data rate of the GSV can be set. Frequencies between
0,3125 Hz and 2000Hz can be selected. For example: At a data range of 100 Hz,
100 values per second will be sent via the serial interface. The bandwidth of the digitized
sensor signal depends on this data rate and on the settings of the analog and the digital
filter.
The transmitted register value N does not consist the data rate itself. You can get the
data rate parameter N using the following formula:

N

f

Data

⋅

=

512

10

7

N =

19531.25

fData

Attention: After a change of the data rate a calibration with set cal and set zero is
necessary.

Affected register: Frequency
With the GSV-21 (new version, SerNo >=06xxxxxx), the data rate cannot be set
continuously. Instead, a combination of the ADC conversion rate and an internal
averaging factor will be selected by the GSV-21, whose combination results in the real
data rate, which is closest to the desired value transmitted as parameter.
Absolute Value Range: 0x00.00..0xFA.12

The allowed value range of the data rate depends on the baud rate and on the data
output format.

The following maximum values apply for:

Baud rate (default value:

38400 Bits/s)

Maximum data rate Binary
output (5 Bytes/measuring

value) in Hz

Maximum data rate ASCII-

output in Hz

4800 90,9 25

9600 181,8 50
19200 333,3 100
38400 625 200
57600 1071 285,7

115200 2000 666,7

Possible error codes 0xA0,0x54,0x58,(0x80),0x71

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Set gain

Command number: 19
Number of parameters: 1
Bytes sent by the GSV: 0

Set gain sets the amplification of the AD-converter of the GSV as shown in the following
table, which indicates the resulting value of the input sensitivity of the bridge input. The
Gain-Parameter 2 is the normal-input sensitivity, it means that the amplification of the
AD-converter is 1. The gain register has no affect on the analog output.

Gain
Parameter

Amplification
of the AD
converter

JP1 setting 1 JP1-setting 2 with

Input Sens= 2mV/V

2

JP1-setting 2 with
Input Sens=
3,5mV/V 2

0

1

0,25 4 mV/V 8 mV/V 14 mV/V
1 0,5 2 mV/V 4 mV/V 7 mV/V
2 1 1 mV/V 2 mV/V 3,5 mV/V
3 2 0,5 mV/V 1 mV/V 1,75 mV/V
4 4 0,25 mV/V 0,5 mV/V 0,875 mV/V
5 8 0,125 mV/V 0,25 mV/V 0,4375 mV/V
6 16 0,0625 mV/V 0,125 mV/V 0,21875 mV/V

Attention: After a change of the amplification a calibration with set cal and set zero is
necessary.

Affected register: Gain.
Value Range: 0x00..0x06

Possible error codes 0xA0,0x54,0x71

Set bipolar

Command number: 20
Number of parameters: 0
Bytes sent by the GSV: 0

Set bipolar sets the GSV in the bipolar mode. Zero corresponds to the data value
0x800000 hexadecimal.
Possible error codes 0xA0,0x71

Set unipolar

Command number: 21
Number of parameters: 0
Bytes sent by the GSV: 0

Set unipolar sets the GSV in the unipolar mode (the measured value 0 correspondents to
the data value 0).

Possible error codes 0xA0,0x71

2 Have a look at Set/Get Range
1 The final value of the input sensitivity can not be reached, because a digital over flow would occur.

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Read Frequency

Command number: 22
Number of parameters: 0
Bytes sent by the GSV: 3

The 3 parameter bytes returned from the command ReadFrequency are coding the
measuring data rate.
With the GSV-21 the data range is not continuously settable (look at Set Frequency).
That's why the decoded data rate read with Read Frequency may vary a little bit from the
value setted before (e.g. with Set Frequency).

The decoding formula for the command 22 is:

Data rate = 5000000 / (16777216 – register value read)

Possible error codes 0xA0,0x91,(0x81)

Get norm

Command number: 26
Number of parameters: 0
Bytes sent by the GSV: 3

Get norm determines the scaling factor register value, as described in set norm (without
the related decimal point setting).
Possible error codes 0xA0,0x91

Get unit

Command number: 27
Number of parameters: 0
Bytes sent by the GSV: 1

Get unit determines the unit register, as described in set unit (look at the list of unit
codes).
Possible error codes 0xA0,0x91

Get dpoint

Command number: 28
Number of parameters: 0
Bytes sent by the GSV: 1

Get dpoint determines the decimal point, as described in set dpoint.
Possible error codes 0xA0,0x91

Switch

Command number: 29
Number of parameters: 1
Bytes sent by the GSV: 0

Switch switches the switch output corresponding to the parameter byte, which is either on
(1) or off (0). The state of the switch output only remains if the measured value is within

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the switch thresholds (with window comparator turned off). The thresholds can be set with
set threshold. Thresholds at the measuring range end deactivate the threshold switch, so
that the switch command should have effect regardless of the thresholds.
Value Range: 0x00..0x01

Possible error codes 0xA0,0x71

Get serial number

Command number: 31
Number of parameters: 0
Bytes sent by the GSV: 8

Get serial number determines the serial number of the amplifier as an ASCII character
string.

Possible error codes 0xA0,0x91

Set threshold 1

Command number: 32
Number of parameters: 4
Bytes sent by the GSV: 0

Set threshold 1 set the threshold of the amplifiers first threshold switch (terminal No 11).
The first two parameter bytes are the switch on threshold, the next two bytes are the
switch off threshold,both with the MSByte first. The switch on threshold always needs to
be bigger than the turn off threshold. You can change the threshold functionality between
hysteresis switch and window comparator. In the latter case, the values are to be
interpreted as upper and lower switch thresholds.
Value Range: 0x00.01.00.00..0xFF.FF.FF.FE

Possible error codes 0xA0,0x56,0x71

Get threshold1

Command number: 33
Number of parameters: 0
Bytes sent by the GSV: 4

Get threshold determines the thresholds of the first threshold switch, as described in
set threshold.

Possible error codes 0xA0,0x91

Set channel

Command number: 34
Number of parameters: 1
Bytes sent by the GSV: 0

Set channel Sets the analogue input channel of the AD- Converter and restores the
operating parameters previously stored for this channel.
Channel=0 : bridge input (terminals 2..7)
Channel=1 : analog-measuring input (terminals 8 and 10)
Value Range: 0x00..0x01
Possible error codes 0xA1,0x54,0x71

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Stop transmission

Command number: 35
Number of parameters: 0
Bytes sent by the GSV: 0

Stop transmission stops the serial transmission of the measuring values. The serial
transmit buffer of the GSV will be emptied. This operation status will get lost after turning
off the amplifier.
Possible error codes 0xA0,0x71

Start transmission

Command number: 36
Number of parameters: 0
Bytes sent by the GSV: 0

Start transmission starts the serial transmission of the measuring values, if they have
been stopped with „stop transmission“ before.
Possible error codes 0xA0

Clear buffer

Command number: 37
Number of parameters: 0
Bytes sent by the GSV: 0

Clear buffer deletes the output buffer of the GSV.
Possible error codes 0xA0

Set mode

Command number: 38
Number of parameters: 1
Bytes sent by the GSV: 0

Set mode configures the GSV for different modes of operation. As with most of the
operating parameters, this mode remains as it is even after turning the amplifier off.
Before you change particular bits of the mode-register you should to read it with
get mode, change the bits as desired and write the byte back (read-modify-write). You
can only change bits 1..5. Description of the mode-variable:

MSB Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 LSB
blocking x AV-

Filter

Window c. mode Log-Mode Max-Mode Text-Mode reserved

Text-mode = 1: measuring value transmission in ASCII-Format is active
Max-Modus = 1: maximum value transmission is active

Log-Modus = 1: transmission of measuring values on request only is active
Window-Modus = 1: threshold switch works as window comparator
AV-Filter =1: Adaptive averaging filter is on. Can only be enabled, if SpecialMode,FIR =0
Block: =1: Blocking-State: All Set- Write-commands will be rejected (see Switch

Blocking) Read only

x: do not change because of upwards compatibility

(read GSV mode before)

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Value Range: 0x00..0x1E

Functionalities of activating the tare line (Input "T")

Sending of
measuring value

Sending of
maximum value

zero
adjustment

Reset Maximum

value
Log-Mode= off
Max-Mode = off

No (is permanently
sending measuring
values)

no yes no (irrelevant)

Log-Mode = off
Max-Mode = on

no no (is sending

permanently max­values)

yes yes

Log-Mode = on
Max-Mode = off

yes no no no (irrelevant)

Log-Mode = on
Max-Mode = on

no yes yes yes

Possible error codes 0xA0,0x56,0x59,0x71

Get mode

Command number: 39
Number of parameters: 0
Bytes sent by the GSV: 1

Get mode reads the operation mode of the GSV, see set mode.

Possible error codes 0xA0,0x91

Get equipment

Command number: 41
Number of parameters: 0
Bytes sent by the GSV: 1

Get equipment reads informations about the hardware configuration of the GSV.
Description of the equipment-variable:

MSB Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 LSB

x x AnaFilt x SI x ADC LCD
LCD = 1: Liquid Crystal Display installed
ADC = 1: Analog-Digital-Converter (always) existing
SI = 1: GSV is intended for use as strain indicator
AnaFilt: =1: Switchable analogue input filter available
x: reserved, not defined
Possible error codes 0xA0,0x91

Firmware version

Command number: 43
Number of parameters: 0
Bytes sent by the GSV: 2

Firmware version reads the version-number of the GSVs firmware. The first Byte is the
version-number multiplied by ten. The second byte contains the revision number.
Possible error codes 0xA0,0x91

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Set gage factor

Command number: 44
Number of parameters: 2
Bytes sent by the GSV: 0

Set gage factor sets the gage factor. When using the GSV as a strain indicator, the
display scaling factor can be recalculated by the command Calc Norm, using the gage­factor, the bridge type and the poissons ratio stored (the latter only if applicable). The
gage-factor register is transmitted as an integer value, as the real gage-Factor multiplied
by 100, with the MSByte first.
Value Range: 0x00.09..0x7F.BC (corresponding K-Factor= 0,09 to 327,00).
Possible error codes 0xA0,0x54,0x55,0x71

Get gage factor

Command number: 45
Number of parameters: 0
Bytes sent by the GSV: 2

Get gage factor reads the gage-factor in the format described in Set Gage factor.
Possible error codes 0xA0,0x91

Set poisson

Command number: 46
Number of parameters: 1
Bytes sent by the GSV: 0

Set poisson sets the poissons ratio µ. The poisson is important when calculating strain
gage bridge types with one or two measuring grids which are aligned crosswise. The
poisson register is transmitted as a whole byte, which is the poissons ratio multiplied by

500.
Value Range: 0x00..0xFA (correspondingly 0,000 to 0,500).
Possible error codes 0xA0,0x54,0x71

Get poisson

Command number: 47
Number of parameters: 0
Bytes sent by the GSV: 1

Get poisson reads the poissons ratio as described in Set Poisson.
Possible error codes 0xA0,0x91

Set bridge type

Command number: 48
Number of parameters: 1
Bytes sent by the GSV: 0

Set bridge type sets the bridge type of the strain gage sensor, with which the display
scaling factor can be recalculated by Calc Norm.
0: Full Bridge

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1: Half Bridge
2: Quarter Bridge
3: Half Bridge with transverse contraction
4: Full Bridge with transverse contraction
Value Range: 0x00..0x04

Possible error codes 0xA0,0x54,0x71

Get bridge type

Command number: 49
Number of parameters: 0
Bytes sent by the GSV: 1

Get bridge type reads the bridge type with the coding described before.
Possible error codes 0xA0,0x91

Set range

Command number: 50
Number of parameters: 1
Bytes sent by the GSV: 0

If the Jumper JP1 (see p.62) on the circuit board is in position 2, that means if the supply
voltage of the sensor bridge is =2,5V, you can choose the input sensitivity of the analog
front end of the amplifier with Set Range. The range register transmitted is the real input
range multiplied by ten. Valid values are 20d and 35d; corresponding to 2mV/V or
3,5mV/V.
Value Range: 2 reliable values: 0x14 and 0x23
Possible error codes 0xA0,0x50,0x56,0x71

Get range

Command number: 51
Number of parameters: 0
Bytes sent by the GSV: 1

Get range reads the input sensitivity of the analog input stage of the GSV21, that means
that the position of the jumper JP1 can be determined, too. The range register value is
also relevant for the automatic calculation of the display scaling factor used by the
command Calc norm. The Range register is 10 times of the full-scale input sensitivity
value in mV/V:
10 = 1 mV/V (Jumper position 1); 20 = 2 mV/V; 35 = 3,5 mV/V (both jp. pos. 2)
Possible error codes 0xA0,0x91

Get offset wait

Command number: 53
Number of parameters: 0
Bytes sent by the GSV: 1

Get offset wait determines the time, which the command set offset needs for execution.
The value read has to be multiplied by 0,0062 to get the wait time in seconds.

Possible error codes 0xA0,0x91

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Get options

Command number: 54
Number of parameters: 0
Bytes sent by the GSV: 3

Get options Determines information about the range of the instruction set and about
special characteristics of the firmware as a 24 bit value. With the GSV-21 bit 6 and bit 8
are always set. The lower 6 bit value is to be interpreted as a whole number within the
range from 0..63 and contains the identification of a possible special application. If this
identification is different from zero you may have to expect restrictions of the firmware
functionalities.
Possible error codes 0xA0,0x91

Get value

Command number: 59
Number of parameters: 0
Bytes sent by the GSV: 5 (at a binary data transmission)

Get value triggers the transmission of a measuring value.
Normally the device transmits measuring values permanently, so this command is of
special interest if that transmission was stopped by stop transmission (command 35) or
if the logger mode is active; see set mode. The data format of the value returned by the
GSV correspondents to the data format of the permanent transmission (binary or ASCII),
as described in the chapter Data format (page 8).
Possible error codes 0xA0,0x91

Clear maximum value

Command number: 60
Number of parameters: 0
Bytes sent by the GSV: 0

Clear maximum value resets the actual maximum value, if the maximum mode is active

(look at set mode), so that a new maximum value can be generated.
Possible error codes 0xA0,0x71

Set Digits

Command number: 61
Number of parameters: 1
Bytes sent by the GSV: 0

Set Digits sets the number of the digits shown in the LC-Display. If the ASCII-data output
is active (by Set Mode), the number of the transmitted digit bytes is set as well. The
allowed value range of the digits is decimal point to 8, that means the number of digits is
not allowed to be smaller than the decimal point position (look at Set Dpoint).
Absolute Value Range: 0x01..0x08

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Possible error codes 0xA0,0x54,0x71

Get Digits

Command number: 62
Number of parameters: 0
Bytes sent by the GSV: 1

Get Digits determines the number of digits shown in the LC-Display.
Possible error codes 0xA0,0x54

Get Channel

Command number: 65
Number of parameters: 0
Bytes sent by the GSV: 1

Get Channel reads the the active analog input channel. In the standard version there are

two inputs available, the bridge input (channel 0) and the channel 1, which has an input
voltage range from 0 to 10V.
Possible error codes 0xA0,0x91

Get Last Error

Command number: 66
Number of parameters: 0
Bytes sent by the GSV: 1

With get last error the the error status of the last command given can be determined.
Every command – with the exception of Get last error itself – overwrites the error register.
That is useful to determine the reason for the rejection of a write command. The command
Reset status (No. 0) resets the error register to 0.
The following error codes are actually defined:

Default: (no command given or error code cleared): 0x00
No Error (OK), no additional parameter changes made: 0xA0
No Error (OK), but* additional parameter changes made: 0xA1

From here on: command given was rejected because:

Command number not existent: 0x40
Command No existent but not implemented in this Firmware: 0x41

Access denied (unspecified): 0x70
Access denied, because "Blocking" is active: 0x71
Access denied, because password not given or incorrect: 0x72
Access denied, because configuration jumper is not set: 0x73
Access denied, because number of allowed executions is too high: 0x74
Access denied, because Set/Write prohibited at this port: 0x75

wrong parameter, (unspecified): 0x50
wrong parameter, (partly) wrong bits: 0x53
wrong parameter, parameter absolutely too big: 0x54
wrong parameter, parameter absolutely too small: 0x55
wrong parameter, invalid parameter combination: 0x56
wrong parameter, parameter relatively** too big: 0x57
wrong parameter, parameter relatively** too small: 0x58

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wrong parameter, functionality not implemented in this FW: 0x59
Not enough parameters or parameter timeout: 0x5A

Sending of parameters was impossible (unspecified): 0x90 (reserved)
Sending of parameters was impossible because tx-buffer was full: 0x91
Sending of parameters was impossible because (CAN-)Bus busy: 0x92
Execution was impossible because the receive buffer is full: 0x99

From this point: former command was eventually accomplished but:

Internal error (unspecified): 0x80
Intern arithmetical error: 0x81
Error at AD-converter settings 0x82
Error: measuring value unsuitable for desired action 0x83
EEPROM-Error (FW-Version 1.2.00 and above only) 0x84

* possibly; mainly additional parameters were loaded, that are not directly associated to this command. Also, no
additional parameters may have changed because the former settings and the loaded settings are similar.
** because of prohibited setting combinations

Set second threshold

Command number: 67
Number of parameters: 4
Bytes sent by the GSV: 0

Set second threshold set the threshold of the amplifiers second threshold switch
(terminal No 13). The first two parameter bytes are the switch on threshold, the next two
bytes are the switch off threshold,both with the MSByte first. The switch on threshold
always needs to be bigger than the turn off threshold. You can change the threshold
functionality between hysteresis switch and window comparator. In the latter case, the
values are to be interpreted as upper and lower switch thresholds.
Value Range: 0x00.01.00.00..0xFF.FF.FF.FE

Possible error codes 0xA0,0x56,0x71

Get second threshold

Command number: 68
Number of parameters: 0
Bytes sent by the GSV: 4

Get second threshold determines the thresholds of the second threshold switch, as
described in set second threshold.

Possible error codes 0xA0,0x91

Get device Type

Command number: 69
Number of parameters: 0
Bytes sent by the GSV: 1

Get device Type reads the type number of the GSV, with the GSV-21 constantly 21d.

Possible error codes 0xA0,0x91

calc norm

Command number: 70
Number of parameters: 0
Bytes sent by the GSV: 0

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Calc norm triggers the calculation of the display scaling factor according to the strain

indicator functionality. Hereby the K-factor, the bridgetype, the input sensitivity and ­depending on the bridgetype - the poissons ratio will be concidered. At the same time
channel 0 will be setted, as well as the amplification of the AD-converter setted to one and
the unit shown to µm/m.

Possible error codes 0xA1,0x81,0x71

Set TXmode

Command number: 128
Number of parameters: 1
Bytes sent by the GSV: 0

With Set TX mode changes can be done to the serial data protocol. This command can
only be executed if the configuration jumper JP2 is set, see Set Baud (next page), the
changing procedure in also described there. With Bit 7 of the parameter byte the
hardware-handshaking can be enabled, with bit 3 the size of the measuring data frame
can be changed from 5 Bytes (bit 3 =1, default setting) to 3 bytes (bit 3 =0). The 3-byte­protocol has 0xA5 as the prefix byte, then follows the measuring value as 16 bit value with
the MSByte first. Higher data rates are possible with this protocol.

Hardware Handshake may be better – in some cases even necessary – if the GSV-2s serial port is
connected to a bus-system or a wireless transmitter.

MSB Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 LSB

Is H.sh. x x x Is 5 Byte x x x
Is 5 Byte =1: if the binary transmission protocol is aktive (see Set Mode), the measuring value frame consists
of 5 bytes.
Is H.Sh. =1: Hardware handshake (RTS/CTS) enabled. Only possible with HW-Handshake special version.
X: Reserved. Do not change.

GetTXmode

Command number: 129
Number of parameters: 0
Bytes sent by the GSV: 1

With GetTXmode you can read flags about the features of the measuring value
transmission protocol.

MSB Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 LSB

Is H.sh. x x WRacc Is 5 Byte x x Configuration

Configuration: If =1, the jumper JP2 for the configuration mode id set. Read Only!
Is 5 Byte =1: If the binary transmission protocol is active (see Set Mode), the measuring value frame consists

of 5 bytes.

Wracc =0: RS232 serial port has write access. =1: All Write Commands blocked. Read Only!
Is H.Sh. =1: Hardware handshake (RTS/CTS) enabled. Only possible with HW-Handshake special version.
X: Reserved. Do not change.

Possible error codes 0xA0,0x91

SetBaud

Command number: 130
Number of parameters: 1
Bytes sent by the GSV: 0

With SetBaud you can determine the bitrate of the serial communication. The bitrate can
only be changed if the jumper for the configuration mode JP2 is set, see p.62. The

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procedure to change the bitrate is: turn off – set the jumper – turn on- open serial interface
with 38400 bps – program desired new bitrate with SetBaud – turn off – remove JP2 –
turn on. Then the new bitrate should be activated.

The bitrates are coded as follows:

Parameter / Register Baudrate
0 4800
1 9600
2 19200
3 38400
4 57600
5 115200
6 250000
7 625000
8 1,25M
9 (only Firmware-Version 1.3.06 and above) 230400
10 (only Firmware-Version 1.3.06 and above) 460800
11 (only Firmware-Version 1.3.06 and above) 921600

The command execution will be denied if the actual data rate is too high for the desired bit
rate.

If the jumper JP2 is set to the configuration mode, the communication bitrate is always
38400 bits/s, independently of the baud register value. The bitrate in the baud register
applies only when jumper JP2 is removed.

Possible error codes 0xA0,0x54,0x58,0x73,0x71

GetBaud

Command number: 131
Number of parameters: 0
Bytes sent by the GSV: 1

With GetBaud you can read the baud register as described before.

Possible error codes 0xA0,0x91

Set Slow Rate

Command number: 134
Number of parameters: 2
Bytes sent by the GSV: 0

If the Slow-flag in the SpecialMode reagister ist set (see Set Special mode), measuring
values will be transmitted with the data period in seconds, that you can set with this
command. The slow mode data period is transmitted with the MSByte first, the value
range is from 1 s to 65535 s.

Possible error codes 0xA0,0x71,0x55,0x5A

Get Slow Rate

Command number: 135
Number of parameters: 0
Bytes sent by the GSV: 2

With Get Slow rate the data period of the slow mode can be read.

Possible error codes 0xA0,0x91

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SetSpecialMode

Command number: 136
Number of parameters: 2
Bytes sent by the GSV: 0

With the Special-Mode-Register some special features of the GSV-21 can be set.
The content of high byte is shown in the following table:

MSB Bit 14 Bit 13 Bit 12 Bit 11 Bit 10 Bit 9 Bit 8

NoiseCut AutoZero x x x AbsMax LngEn Storing Behaviour
Storing Behaviour: If =1, all changes of all operating parameters are stored in the non volatile EEPROM
memory immediately after changing them. If =0, most operating parameters are stored after the device is
switched off. If power-on-cycles (switching on and off) are done more often than changing of values will be
done, setting of this flag is recommended. If changing of values is done more often, leave it =0 (default
setting).

LngEn: =1: Display menu language is english. =0: Display menu language is german
AbsMax: If Max-mode also set (s. SetMode): =1: The maximum of the absolute value of the measuring value

is transmitted
AutoZero: (only if available, see GetCommandAvailable, otherwise X): =1: Automatic periodical zero-point
adjustment enabled, see SetAutoZeroCounter, command 150.
NoiseCut: (only if available, see GetCommandAvailable, otherwise X): =1: Noise Supression enabled, see
SetNoiceCutThreshold, command 148.

The content of the low byte is shown in the table below:

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 LSB

Unipolar-

Mode

x FIR_N5 AutoFilt Select.TX FIR-Filter MW-Filter Slow

Slow: =1: Slow mode enabled. In this mode, mesuring values are transmitted with data periods >= 1 s. This
period is communicated with the commands 134 / 135. The data rate communicated with commands
138/139, 3/7 and 18/22 is not valid in this mode.

MW-Filter : Read-Only Flag: Is =1, if Mwsum is >1 (see commands 138, 139)
FIR-Filter : =1: Turns on FIR-Filter; a digital low pass filter, which takes place after the firmware-internal

decimating average filter. Its cut-off frequency depends on the measuring data rate.
Select.TX: Selective Transmission: If this flag is =1 and the maximum value mode is enabled (see command
Set Mode), only new maximum values will be transmitted, in order to avoid redundancy transmission.
AutoFilt: if =1 (default setting), the analogue pre filter will be set automatically according to the datarate
Fdata.
In this case the cut-off frequency fg of the analogue filter will be set as follows:

switches fg = 3,5 Hz switches fg = 260 Hz switches fg = 1,7 kHz

FIR-Filter off if Fdata <= 7,14/s if 7,14/s < Fdata < 625/s if Fdata >= 625/s
FIR-Filter on if Fdata <= 15/s if 15/s < Fdata < 1071/s if Fdata >= 1071/s

FIR_N5: Defines the characteristic of the digital FIR-filter, if the FIR-Filter is on (Bit 2=1). If the FIR_N5 is =0,
it is a second order FIR filter, its -3dB-cut-off frequency is = Datarate * 0,18 and its transfer function is gentle,
without overshot in the step response its operating time is only 3 measuring values. If FIR_N5 =1, it's a 5th
order FIR filter. Its cut-off frequency is = datarate * 0,25 and its transfer function is much steeper in the
attenuating band, but with 6% overshoot in the step response; and the operating time takes 6 measuring
values. That's why the FIR-Filter 5. order is more recommendable at higher data rates, if (for example for
vibration analysis) a quite linear frequency response in the transmission range and a steep tapered is desired
in the attenuating band.

Unipolar-Mode : Read-Only Flag. Shows if the unipolar- or bipolar-Mode
is set, see commands 20/21.
x: Reserved, do not change; should be the same as the value read, see GetSpecialMode.

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Possible error codes 0xA0,0x53,0x59,0x71

GetSpecialMode

Command number: 137
Number of parameters: 0
Bytes sent by the GSV: 2

With GetSpecialMode you can read the register described before.

Possible error codes 0xA0,0x91

WriteSamplingRate

Command number: 138
Number of parameters: 3
Bytes sent by the GSV: 0

This command sets the sampling rate of the AD converter and the number of summands
of the decimating average filter and as such also the resulting data rate.
The sampling rate determines how many analogue-digital conversions the AD-converter
does per second.
The relation between measuring data range and sampling rate is as follows:
measured data range = sample rate / averaging summand amount
The value range of the averaging summand is from 1 to 11.

Parameter 1: Number of averaging summands
Parameter 2: High byte of the Sampling-Rate-Register
Parameter 2: Low byte of the Sampling-Rate-Register

Parameter 1:
Bits 6 und 7 must be =1. Examples:

0xC1 means that the decimating average filter is disabled.
0xCB means that the averaging filter decimates over 11 values.

Parameter 2 and 3:

the computation formula for the Sampling-Rate-Register (second and third Parameter) of
command 138/139 is:
Registervalue = sample rate * 2
Der AD-converter of the GSV-21 supports the following discrete sampling rates:

2.5, 5, 10, 15, 25, 30, 50, 60, 100, 500, 1000, 2000, 3750, 7500 and 15000 samples per
second. If the value coded by parameter 2 and 3 differs from these values, the closest
available sampling rate will be set. If the resulting measuring data rate would be too high
(see table in the Set frequency description) or too low (below 0.3125/s), the command is
rejected.
Absolute Value Range: 0xC8.00.05..0xC1.75.30

Possible error codes 0xA0,0x53,0x54,0x55,0x57,0x58,(0x80),0x71

ReadSamplingRate

Command number: 139
Number of parameters: 0
Bytes sent by the GSV: 3

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With ReadSamplingRate the sampling rate and the number of the averaging values can
be read, as described in WriteSamplingRate:
Byte 1: Number of the average values in Bits <5:0>, Bits 6 and 7 =1
Byte 2: Highbyte of the Sampling-Rate-Register
Byte 2: Lowbyte of the Sampling-Rate-Register
Whereby: sampling rate = Sampling-Rate-Register / 2

Possible error codes 0xA0,0x91

Set CAN Setting (Only existent with GSV-2-CANopen)

Command number: 140
Number of parameters: 3
Bytes sent by the GSV: 0

With Set CAN Setting fundamental properties of the CANopen-Interface can be changed.
The parameter to change (CAN-Flags, CAN-Bitrate and CAN-Node-ID) is selected with an
index byte, which is passed as the first parameter. Then a WORD-sized data parameter
follows. The parameters are passed in the order: <Index, DataHiByte, DataLoByte>. The
following indices are writable:
Index 0x7F: CAN-Flags: Data-Bits <15:8> (HiByte) are reserved and habe to match – as
the Data-Bits<7:2> of the LoByte - the value read before with Get CAN Setting at Index
0x7F. Bits<7:0> (LoByte) are defined as follows:

MSB Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 LSB
x x x x x x

CANon

HasCAN =1

CANon =1: CAN-Interface enabled. The CAN-Interface can be switched on and off with this. When switched
on, (CANon before =0), the CAN-Interface is „bootet“, which is signalled to the CANbus by putting the bootup­frame (TX-NMT) on the bus.

CANon =0: Switched off. When switching off the CANbus (CANon before =1) waiting CAN-Messages are
aborted and the device disappears from the CAN-Bus, i.e. after switching off it is no CAN-device
anymore!

HasCAN: With CANopen devices always =1, i.e. bit 0 of the passed value must be set (read-only)

x: reserved, has to match the reading value

Possible error codes: 0xA0, 0x71, 0x51, 0x52, 0x5A

Index 0x7E: CAN-Bitrate: With this the bitrate of the CAN interface can be set. The bitrate is coded as
follows:

Data parameter CAN-Bitrate

0x0001 50 kBits/s
0x0005 125 kBits/s
0x0006 250 kBits/s
0x0007 500 kBits/s
0x0008 1 MBit/s

The CAN-Bitrate can only be altered, if the RS232-Interface has write permission. Write permission is
signalled by cleared “WRacc”-Bit in the TxMode value, see GetTXmode (that is the case, if the CAN-Interface
is either off or on, but in the CANopen-State “Stopped”). Also, the configuration jumper JP2 must be set
(see Set Baud).

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After changing, the new CAN-Bitrate will be valid only after a Bootup-cycle (switch on and off) or after a reset
cycle by CANopen network management, if the CAN-Interface is on. If it's off, the new CAN-Bitrate will be
valid when switching on the CAN interface, see CAN-Flags.

Possible error codes: 0xA0, 0x71, 0x73, 0x75, 0x51, 0x52, 0x54, 0x58, 0x5A

Index 0x7D: CAN-Node-ID: With this, the Node-ID of the GSV-2-CANopen (the “Node”) can be altered:
Datenparameter = gewünschte Node-ID. Diese muß im Bereich von 0x0001 bis 0x007F liegen. Die Node-ID
kann nur verändert werden, wenn das RS232-Interface Schreibrecht besitzt. Schreibrecht wird durch
gelöschtes “WRacc”-Bit im Txmode-Wert angezeigt,s. GetTXmode (das ist der Fall, wenn das CAN­Interface entweder aus ist oder an, aber im CANopen-State “Stopped”).

Nach Änderung kommt die neue Node-ID erst nach einem Bootup- (Aus- u. wieder Einschalten) oder einem
Reset-Zyklus per CANopen-Network-Management zur Wirkung, falls das CAN-Interface an ist. Ist es aus,
kommt die neue Node-ID beim Einschalten des CAN-Interfaces zur Wirkung, siehe CAN-Flags.

Mögliche Fehlercodes: 0xA0, 0x71, 0x75, 0x51, 0x54, 0x55, 0x5A

Get CAN Setting

Befehlsnummer: 141
Anzahl der Parameter: 1
Vom GSV gesendete Bytes: 2

Mit Get CAN Setting können Einstellungen des CAN-Interfaces gelesen werden. Die
Wahl der Einstellungsparameter erfolgt hierbei über ein Index-Byte, welches als
Parameter übergeben wird. Der GSV antwortet stets mit 2 Datenbytes mit der Reihenfolge
<HiByte,LoByte>; auch im Fehlerfall (s. GetlastError), dann sind die Datenbytes =0. Bei
den Indizes wird zwischen aktuell eingestellten Werten (Indexbereich 0x5A..0x5F) und
solchen unterschieden, die erst beim nächsten Bootup- oder Reset-Zyklus zur Wirkung
kommen (Indexbereich 0x7A..0x7F). Bei den Einstellungen CAN-Bitrate (Index 7E) und
CAN-Node-ID (Index 7D) sind diese Werte nach einer Änderung mit Set CAN Settings
u.U. jeweils unterschiedlich; der Erfolg von SetCANSetting kann an dementsprechenden
Indizes 0x7D..0x7F ermittelt werden.

Index Aktuell
gültiger Wert

Index Wert nach nächstem
BootUp / Reset

Dateninhalt

assoziiertes
CANopen-Objekt

0x5F

0x7F CAN-Flags, s. Set CAN Settings

-

0x5E 0x7E CAN-Bitrate, s. Set CAN Settings

-

0x5D 0x7D CAN-Node-ID

(1200h/1800.1h)
0x5C 0x7C Producer Heartbeat-Time, in ms 1017h
0x5B 0x7B Event-Timer-Period, in ms 1800.5h
0x5A 0x7A Inhibit-Time, in 100us 1800.3h

Mit Get CAN Setting kann auch ermittelt werden, ob ein CAN-Interface vorhanden ist: An
Index 0x7F lesen und Bit 0 auswerten: =1: CAN vorhanden; =0: CAN nicht vorhanden. In

letzerem Fall ist der Fehlercode =0x41 an jedem Index; Dateninhalt =0.
Mögliche Fehlercodes: 0xA0, 0x51, 0x91, 0x41, 0x5A

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Set analogue filter

Command number: 144
Number of parameters: 2
Bytes sent by the GSV: 0

With Set analogue filter the cut-off frequency of the prefilter can be changed, if the
AutoFilt-Flag of the Special-Mode-Registers is =0, see Set/Get special Mode. This low
pass filter is before the AD-converter and it is able to improve the signal to noise ratio
both of the digital and the analogue output.
The Standard version has 3 limit frequencies:

1. 3,5Hz, 1.order; from 260Hz on: 2.order

2. 260Hz, 1. order; from 1,7kHz on: 2. order

3. 1,7kHz 1. order

The parameter (1. parameter: Highbyte, 2. parameter: Lowbyte) is twice the amount of the
desired cut-off frequency. The cut-off frequency closest to the parameters will be selected
and setted.
Value Range: 0x00.07..0x0D.FF

Possible error codes 0xA0,0x54,0x55,0x56,0x71

Get analogue filter

Command number: 145
Number of parameters: 0
Bytes sent by the GSV: 2

Get analogue filter delivers twice the amount of the cut-off frequency of the analogue
prefilter. Possible return-values in standard version are:
0x00.07: limitfrequency = 3,5 Hz
0x02.08: limitfrequency = 260 Hz
0x0D.48: limitfrequency = 1,7 kHz

Possible error codes 0xA0,0x91

Switch Blocking

Command number: 146
Number of parameters: 3
Bytes sent by the GSV: 0

With Switch Blocking the GSV-21 can be protected against unintentional changes of the
operation parameters. If the blocking status is enabled, every set and write commands will
be refused, the error-code for this case is 0x71. This status can be identified with Get
Mode (Bit 7, read only). Because the GSV commands consist of only one byte, there
could be an accidentally call of commands by the device connected to the serial port (PC,
SPS or other). This may happen because of using a wrong portnumber or a wrong
program and so on. The blocking status is controlled by two constant ASCII-strings as a
parameter for this command:

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Enable blocking: Parameter = "e3F", that is Param.1=0x65, Param.2=0x33,

Param.3=0x46

Disable Blocking: Parameter = "k7B", that is Param.1=0x6B, Param.2=0x37,

Param.3=0x42

Attention: Every other parameter will be interpreted as a wrong blocking-password and after 3 trials
with wrong parameters the command will always be denied (indipendent of the parameter), the error
code in this case is 0x74. After a restart this status will be reset.

Possible error codes 0xA0,0x70,0x74

Get Command Available

Command number: 147
Number of parameters: 2
Bytes sent by the GSV: 1

With Get Command Available it can be examined if commands and their corresponding
functionality are existent with the device connected. Hereby the upper command number
of the command range to be checked will be transmitted first and the lower command
number as the second parameter. Both command numbers may be equal (then only this
command will be checked), but the first parameter should not be smaller than the second,
otherwise the returned byte is an errorcode=0x56 (then similar to LastError).
If all commands in the range to be checked are existent, the byte returned is =0xA0.
Otherwise – if at least one command within the range is not existent - the byte returned is
=0x41.
So, with Get Command Available it can also be examined, if functionalities corresponding
to certain commands are existent (espiecially with commands >=128d), for example:
To examine whether the automatic zero tracking is existent, give command 147 with the
parameters 151d, 150d. These correspond to the command numbers for
Get/SetAutoZeroCounter. If the answer is 0xA0, the automatic zero tracking is existent is
existent, otherwise it's not.
Like this, you may for instance check the CAN-Interface (Parameters 140d, 140d), the
noise-suppression „Noise-Cut“ (Parameters 149d, 148d) or the User-Display-functionality
(Parameter 152d, 152d) or Handshake (Parameter 128d, 128d) and others for their
existence. Advice: The property of existence will never change with the same device exemplar.

(exept maybe after a firmware update by ME-Systeme).

Possible error codes 0xA0, 0x56, 0x5A

Set NoiseCut Threshold (only if NoiseCut existent)

Command number: 148
Number of parameters: 3
Bytes sent by the GSV: 0

With SetNoiseCutThreshold the threshold for the NoiseCut noise suppression can be set.
If this noise suppression is set (see SetSpecialMode, Bit 15), the measuring value output
will be set constatly to zero if the input measuring value is below this threshold (bipolar: if
abs(Messwert) < threshold or -threshold < measuring value < threshold). The number
format of the NoiseCut threshold is the same as the one of the measuring values, see
p.16 and 55. By using this, it can be achieved that the measuring value around zero is
absolutely „quiet“, that means free of noise.

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Example (bipolar):
Shall NoiseCut-Threshold be = 0x810000; then all measuring values, that are between
0x810000 and 0x7F0000, set to 0x800000 exactly.
Value range: bipolar: 0x800000..0xFFFFFF; unipolar: 0x000000..0x7FFFFF

possible error codes: 0xA0, 0x71,0x75, 0x54, 0x55, 0x84, 0x41

Get NoiseCut Threshold (only if NoiseCut existent)

Command number: 149
Number of parameters: 0
Bytes sent by the GSV: 3

With GetNoiseCutThreshold you can read the register described before.

Possible error codes 0xA0,0x91, 0x41

Set AutoZero Counter (only if AutoZero existent)

Command number: 150
Number of parameters: 2
Bytes sent by the GSV: 0

With Set AutoZero Counter the counter for the automatic periodic tare-function can be set.
If this AutoZero function is enabled (see SetSpecialMode, Bit 14), after <AutoZero­Counter> number of mesuring values a zero-point adjustment will be executed
automatically, if the threshold switch 1 „SW1“ is off (meaning the measuring value is below
this threshold). The mesuring values are only counted, if the threshold switch 1 „SW1“ is
off. By using this function, an eventual drift of the measuring value (e.g. because of
temperature drift of the sensor) can be compensated. So, the time-period of this
automatic zero-setting depends on the AutoZero counter and the data rate.
Example (bipolar):
Shall the upper threshold 1 be =0x810000, the data rate = 10/s and the AutoZero-Counter
=100. Then every 10 seconds a zero-point adjustment will be executed automatically, if all
measuring values within this period of time were below 0x810000.
Value range: 0x0001..0xFFFF

Possible error codes: 0xA0, 0x71,0x75, 0x55, 0x84, 0x41

Get AutoZero Counter (only if AutoZero existent)

Command number: 151
Number of parameters: 0
Bytes sent by the GSV: 2

With GetAutoZeroCounter you can read the register described before.

Possible error codes 0xA0,0x91, 0x41

Set UserTextChar (devices with LC-Display only)

Command number: 152
Number of parameters: 2
Bytes sent by the GSV: 0

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With Set UserTextChar a user defined text can be displayed in the LCD. The first
parameter is the adress, that means the position of the character in the display. A text of
up to 16 characters can be displayed, so the value range of this adress is from 0 (left side
of LCD) to 0x0F (right side of LCD); at adress 0x10 a 0x00 for termination can be
transmitted. The second parameter is the character itself, whereby the range of 0x20 ' ' to
0x7D '}' is ASCII-conform (exeption: 0x5D is not '\').
To display a text array, please follow these steps:
The characters are transmitted to the GSV in a descending order, whereby they are
copied to the device's RAM first. If the text array is shorter than 16 characters, a 0x00 as
data for termination must be transmitted first with the adress <text length>. Then the last
character of the text at adress < text length - 1> and so on until the first character of the
text at adress 0. In case the text should begin shifted to the right, please fill up with blanks
(0x20), so that at adress 0 there's a value of > 0x1F. Because that's the signal to display
the text in the LCD (whole text copied from RAM to LCD if data>0x1F at adress 0x00).
Example:
Text = " Txt0" (length =5)
Complete byte sequence transmitted to the GSV
(Form: 0x<BefehlsNo>.<Adresse>.<Data>):
0x98.05.00 0x98.04.30 0x98.03.74 0x98.02.78 0x98.01.54 0x98.00.20

To switch off the displaying of that text, so that the measuring value appears again, you
only have to transmit a 0x00 at adress 0: 0x98.00.00. The text remains in RAM – exept
the first character - as long as the power supply is connected.
To display the same text (stored in RAM) again, you only have to transmit the first
character (>0x1F) again.
Value range:

1. Parameter (adress): 0x00..0x10

2. Parameter (Ascii-character): 0x00, 0x20..0x7F

Possible error codes: 0xA0, 0x71,0x51, 0x52, 0x41

SetUserOffsetValue

Command number: 154
Number of parameters: 3
Bytes sent by the GSV: 0

With SetUserOffsetValue a summand can be passed to the device, that will be added to
every measuring value. The number-representation is the same as with measuring values,
see p. 16 and 55. The UserOffsetValue may be negative in bipolar mode.
(0x400000..0x7FFFFF).
Value range: bipolar: 0x400000..0xBFFFFF unipolar: 0x000000..0x7FFFFF

Possible error codes: 0xA0, 0x71,0x75, 0x54, 0x55

GetUserOffsetValue

Command number: 155
Number of parameters: 0
Bytes sent by the GSV: 3

With GetUserOffsetValue you can read the register described before.

Possible error codes: 0xA0,0x91

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SetAdaptFilterMask

Command number: 158
Number of parameters: 3
Bytes sent by the GSV: 0

With SetAdaptFilterMask the comparison mask of the adaptive averaging filter can be set.
This special digital filter can be enabled or disabled with SetMode (Bit 5). It combines a
moving average filter over up to 32 values with a quick step response of the measuring
signal. „Moving average filter“ means that the filter is non-decimating, so the output data
rate is equal to the input data rate. The filter distincts the wanted signal transient from a
noise signal transient by bitwise comparison of this bitmask with the difference of a
measuring value and its predecessor. If the absolute value of the difference of a mesuring
value Xk and its predecessor Xk-1 abs(Xk – Xk-1) is within this comparison mask (abs(Xk
– Xk-1) <= AdaptFilterMask), this measuring value Xk will be transmitted directly;
otherwise the actual mean value will be transmitted. The comparison mask must have the
following form:
0xFF.xx.00, whereby in the middle byte („xx“) all more significant bits must be =1 and the
least significant bits =0 (example: 0xFF.F0.00).
Value range: 0xFF0000..0xFFFF00

Possible error codes: 0xA0, 0x71,0x75, 0x53

GetAdaptFilterMask

Command number: 159
Number of parameters: 0
Bytes sent by the GSV: 3

With GetAdaptFilterMask the compare mask of the adaptive averaging filter can be set,
see SetAdaptFilterMask and SetAdaptFilterOptimize.

Possible error codes: 0xA0,0x91

SetAdaptFilterOptimize

Command number: 160
Number of parameters: 2
Bytes sent by the GSV: 0

With SetAdaptFilterOptimize the optimum compare mask of the adaptive averaging filter
(see above) can be determined automatically. The number of measuring values, that are
included into this automatic detection, will be transmitted to the GSV by using this
command. Then this „self-learning period“ starts and during this period the GSV is
calculating the peak-to-peak noise and after this number of measuring values has
finished, the comparison mask is calculated, which can then be read with
GetAdaptFilterMask. The adaptive averaging filter must be enabled during this period
(SetMode, Bit 5). During this self-learning period the wanted signal should not change,
since only the peak-to-peak noise should be taken into account.
Examples:
A typical application of this functionality is the so-called „cattle balance“. Let's assume you
have one or more load cells with cattle on top of it, connected to our GSV-2 and now you

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want to attenuate the stamping of the cattle on the balance (that's the noise signal) with
the adaptive averaging filter. Then you would follow these steps:
The adaptive averaging filter must be enabled. Now let some animals go onto the balance
and give then SetAdaptFilterOptimize e.g. with Parameter =200. Then the self-learning
period lasts 20 seconds at a data rate of 10/s. After these 20 seconds the animals may
leave the balance; the „stamping“, that is the noise signal should now be attenuated, so
theoretically reduced by the factor 1/sqrt(32), which is about 1/5.
With the adaptive averaging filter any noise signal, e.g. present in an environment with
harsh elecromagnetic interference can be filtered, that means attenuated. Start the self­learning phase with SetAdaptFilterOptimize with the filter enabled, while the noise signal is
strong, but the wanted signal doesn't change significantly.
A special functionality of SetAdaptFilterOptimize can be triggered with parameter
=0x0000. Then the comparison mask will not be determined automatically, but it will be
selected from 4 constant values considering the data rate. Using this special function is
recommended after changing the data rate, provided the noise signal level at the GSVs
input hasn't changed significantly. Otherwise SetAdaptFilterOptimize with Parameter >4
(self-learning) should be done as decribed, if the data rate has changed.
The following special modes must be disabled in order to execute SetAdaptFilterOptimize;
otherwise the command will be rejected with error code =0x56: maximum value mode,
Slow-mode, NoiseCut, AutoZero.
Value range: 0x0000, 0x0004..0xFFFF

Possible error codes: 0xA0, 0x71,0x75, 0x55, 0x56

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GetAdaptFilterOptimize

Command number: 161
Number of parameters: 0
Bytes sent by the GSV: 2

With GetAdaptFilterOptimize the number of remaining measuring values during the self­learning phase (as described above) can be read, until the self-learning phase is finished.
This is useful to determine when that phase will be finished. As the self-learning is finished
(or wasn't ever started), the answer to GetAdaptFilterOptimize is =0x0000; then the
measuring system can be used again normally.

Possible error codes: 0xA0,0x91

Read Ranges

Command number: 162
Number of parameters: 1
Bytes sent by the GSV: 4

With Read Ranges all configurable input sensitivities can be determined, this means even
those, who are currently not configured. The transfer parameter indicates which of
possible input sensitivities should be read. Here is High-Nibble (bits <7:4>) the channel
coded, which may be only 0 (bit 4 = 0) or 1 (bit 4=1). The lower nibble (bits <3:0>)
indicates whether the currently configured input sensitivity should be read (bits <3:0> =0)
or which of 3 existing input sensitivities levels. These may deviate from standard variant (1
/2 /3,5 mV/V) depending on the option of hardware.
The first byte of return is the socalled „Jumper-Group-ID“, which indicates (Bit4) =0 on the
channel nibble , for which jumper position applies the returned input sensitivity value.
The return value (bytes 2...4, High-endian) indicates the 100 time the input sensitivity in
mV (mV/V), which means it must be divided by 100, to get mV/V, or by 100000 to get
Volt.

Transfer parameter

Value

(Hex)

Meaning Value at standard-version

(decoded, dec.)

0x00

Currently configured input sensitivity 1 / 2 / 3,5 mV/V / 10V

0x01

First input sensitivity for setting 1 of JP1 (s.S.Error:
reference not found)

1 mV/V

0x02

First input sensitivity for setting 2 of JP1 2 mV/V

0x03

Second input sensitivity for setting 2 of JP1 3,5 mV/V

0x10

Input sensitivity of channel 1 (if it is now activ) 10 V

0x11

Input sensitivity of channel 1 10 V

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Meaning of the Jumper-Group-ID bytes of answer:

Value (Hex) Meaning

0x01 Jumper 1: position 1. if transfer param. =0: Jumper is in position 1
0x02 Jumper 1: position 2. if transfer param. =0: Jumper is in position 2
0x03 Channel 1
0xFF Error

Possible error codes: 0xA0,0x59,0x91

Get Sensor Capacity

Command number: 164
Number of parameters: 0
Bytes sent by the GSV: 4

With Get Sensor Capacity the previously saved physical characteristic value of the
connected sensor can be read. The return parameter is encoded as floating point number
to basic 10, whereby the first byte indicates exponent +1 and the bytes 2 to 4 the mantissa
in High-endian order. The returned mantissa is the 1000000 time mantissa In point
presentation. Example:
The return is 0x04, 0x26.25.A0
The decimal exponent is then 0x04 -1 = 3.
Mantissa must be divided by 10^6, in this example: 2 500 000 / 10^6 = 2,5
The characteristic value is then: 2,5 * 10^3 = 2500.
possible error code: 0xA0,0x91

Set Sensor Capacity

Command number: 165
Number of parameters: 4
Bytes sent by the GSV: 0

With Set Sensor Capacity the physical value of the connected sensor can be saved. The
transfer parameter is thereby as floating point number to basic 10 coded, whereby the first
byte indicates exponent +1 and the bytes 2 to 4 the mantissa in High-endian order. The
transferred mantissa is the 1000000 time mantissa in point presentation. Example:
Shall the characteristic value be 150, this means 1,5 * 10^2 (1,5E2)
The exponent byte is then 0x03 (2 +1).
The mantissa must be multiplied by 10^6, in this example: 1,5 * 10^6 = 1.500.000
value range uncoded: 0,01 bis 9.999.999
value range exponent byte: 0x00 bis 0x07
value range mantissa: 0x0186A0 bis 0x98967F
possible error code: 0xA0,0x54,0x55

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Get Rated Output

Command number: 166
Number of parameters: 0
Bytes sent by the GSV: 4

With Get Rated Output previously saved electrical characteristic value of the connected
sensor can be read. The return parameter is thereby coded as floating point number to
basic 10, whereby the first byte indicates exponent +1 and the bytes 2 to 4 the mantissa in
High-endian order. The returned mantissa is the 1000000 time the mantissa in point
presentation. Example:
Shall the return be 0x01, 0x35.67.E0
The decimal exponent is then 0x01 – 1 = 0.
The mantissa must be divided by 10^6, in this example: 3.500.000 / 10^6 = 3,5
The electrical characteristic value is then: 3,5 * 10^0 = 3,5.
possible error code: 0xA0,0x91

Set Rated Output

Command number: 167
Number of parameters: 4
Bytes sent by the GSV: 0

With Set Rated Output the electrical characteristic value of the connected sensor can be
saved. The return parameter is thereby coded as floating point number to basic 10,
whereby the first byte indicates exponent +1 and the bytes 2 to 4 the mantissa in High­endian order. The returned mantissa is the 1000000 time the mantissa in point
presentation.

The transferred exponent depends thereby on the input sensitivity:

Input sensitivities

Channel 0

Exponents byte Value range (decimal, uncoded)

0,1 / 0,2 / 0,35 mV/V

0x00

0,001 to 0,9999999 mV/V

1 / 2 / 3,5 mV/V

0x01

0,01 to 9,999999 mV/V

10 / 20 / 35 mV/V

0x02

0,1 to 99,99999 mV/V

100 / 200 / 350 mV/V

0x03

1 to 999,9999 mV/V

The input sensitivity should have been determined before with Read Ranges.
Example:
Shall the electrical characteristic value be 2,123456 mV/V
Shall the input characteristic value be 3,5 mV/V
The exponent byte is then 0x01
The mantissa must be multiplied by 10^6, in this example: 2,123456 * 10^6 = 2.123.456
Bytes to eb transferred are then: 0x01, 0x20, 0x66, 0xC0

Value range exponent byte: 0x00 bis 0x03, defined with input sensitivity
Value range mantissa: 0x002710 bis 0x98967F

possible error code: 0xA0,0x54,0x55,0x56

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Get SensorText Assign

Command number: 168
Number of parameters: 0
Bytes sent by the GSV: 2

With Get SensorText Assign information about the assignment of settings to the saved
sensors and their names defined by user can be read.
The answer contains two parameters, each is 1 byte big. The first byte is the assignment
number. If it is =0, then there is no sensor(text) assigned to the settings. Otherwise it
describes the number (1 to 6) of user data record, in which the copy of the settings
belonging to sensor is taken (see Cmd 9/10: Get All / Save All).
The second byte contains flags about the presence of sensortext, s. table. If the bit is set,
there is a valid text, otherwise the bit is =0.
See also the next chapter “Using and managing of the user data record assigned text”.

Data record-Nr.
(frist byte of
answer)

Address range of
sensor text (s.
Cmd. 56/57), Hex

Address range of
sensor text (s. Cmd.
56/57), Dec

Bit-Nr. Second byte of answer. Bit =
1: text available

1 0x300...0x30D 768...781 Bit 0
2 0x310...0x31D 784...797 Bit 1
3 0x320...0x32D 800...813 Bit 2
4 0x330...0x33D 816...829 Bit 3
5 0x340...0x34D 832...845 Bit 4
6 0x350...0x35D 848...861 Bit 5

CANbus / CANOpen protocol of the GSV-2-CANOpen

Conformity: CiA 301 (communication) and CiA 404 (application)
Other documents: gsv2can.eds, ba-gsv2CanOpen.pdf

Connecting the CAN-Bus wires

The CAN-Bus wires are connected to the terminals D, E and F:

Terminal Description

D CAN-GND
E CAN-L
F CAN-H

The CAN-Interface is galvanically isolated.

Bus-termination

Just behind the 15-pole terminal block there's a 2-pole pin-connector for the bus­termination. By closing these 2 pins with a jumper (1/10'' spacing) the bus-termination is
enabled.

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Supported services

• 5 different mandatory RX-NMT objects for the state-management (see CiA 301)

• Heartbeat-producing with indication of the actual state and bootup-frame

• 1 Tx-PDO for measuring values

• 37 different SDOs in the Object dictionary, two of them manufacturer-defined, see

EDS

Interpretation of the 1st Tx-PDO

After Bootup the device is in the Preoperational state. In order to let the device send the
1st Tx-PDO, the „Enter Operational state NMT“ must be transmitted to the device. If all
other send-conditions are met (see below), the following PDO-frames are sent, in time­order from left to the right:

Analog Input Process Value A.Input Status Alarm Status

LSByte Byte 1 Byte 2 MSByte Byte Byte

In the default configuration, the Analog Input Process Value ia a Signed-Integer 32
number, which must be interpreted as following, to get scaled measuring-values:
Measuring value = Analog_Input_Process_Value_Raw_Value /
(10^Analog_Input_Decimal_Digits)

So, for interpretation the object 6132h (Analog_Input_Decimal_Digits) must be read once
and the A.I.Process_Value_Raw_ Value must then be divided by the power of the
Analog_Input_Decimal_Digits to the base of 10.
With the object 6126h the Analog Input Process Value can be scaled, to customize it to
the application requirements. By writing to 6126h the Analog_Input_Decimal_Digits may
get altered in the background, so after writing to 6126h the object 6132h should be read
again. Changing the Physical Units (Object 6131h) hasn't any influence on 6126h and on
6132h.
Future versions (from firmware version 1.4 on) will be able to transmit the Analog Input
Process Value as a float, scaled directy to physical units, so that this lavish interpretation
won't be necessary anymore.

The Analog Input Status Byte contains the following flags:
Bit 0 (LSBit): (still reserved, =0; future versions: sensor broken)
Bit1: Positive overflow of the measuring value
Bit2: Negative overflow (=underflow) of the measuring value
Bits 3..7: =0
With the GSV-2CANOpen, the Alarm Block is implemented as the threshold switch,
whereby the measuring value is compared to a threshold and the threshold switching
output is set on or off. The status of these switches are part of the Alarm Status.
The Alarm Status Byte contains the following flags:
Bit 0 (LSBit): Threshold switch 1 activated
Bit 1: Threshold switch 2 activated
Bits 2..7: =0

Send-conditions for the 1st Tx-PDO

• State = operational AND

• PDO = valid (Object 1800.1 Data-Bit 31 =0)

AND if Transmission-Type (1800.2) = 255 (default setting):

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• Event-Timer (1800.5) ready OR

• Changing of measuring value >= Analog Input Delta Transmission Value (6133h),

if 6133.1 > 0
If the Transmission-Type is = 254, the Event-Timer is ignored.
If the Inhibit-Time (1800.3) is >0 and not expired yet, no further PDO will be transmitted.

Default settings:

CAN-Bitrate 500kBits/s
Node-ID 0x40
Transmission-Type (Obj. 1800.2) 255
Inhibit-Time (Obj. 1800.3) 0, that means disabled
Event-Timer (Obj. 1800.5) 0x03E8, that means 1 PDO /s
Analog Input Delta Transmission Value

(Obj. 6133.1)

0, that means Delta-Interrupt-function
disabled

Producer Heartbeat Time (Obj. 1017) 0, that means Heartbeat disabled. The

Bootup-frame will be sent once after power-up
or after reset.

All other objects and settings: see EDS and ba-gsv2CanOpen.pdf

General advices and Tips

Please attend the actual documents on:
http://www.me-systeme.de/software.html

The command number is transmitted as a single byte to the measuring amplifier.

The command parameters and the return parameters are binary bytes and not numerical
(ASCII-) values (e.g. the parameter „01“ means 0x01 and not 0x31).

A Windows dynamic-link-library (MEGSV.DLL) to access all the features of the measuring
amplifier is available, also a LabView example VI with dll-function wrapper-VIs.

For direct programming via RS232 it is sometimes easier to use the text format for
measuring values, provided that the scaling factor was calculated correctly, according to
the application requirements, since in text format the GSV-2 itself does the multiplication
of the raw values with the scaling factor.

Otherwise, in the binary format every measuring value needs to be multiplied with the

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scaling factor, in order to show physical measurement values (for example ±2mV/V). To
calculate measuring values scaled in physical units please calculate as follows:

1. Without using the Windows-DLL, Mode „bipolar“:
Measuring value = ((Raw binary – 8388608) / 8388607) * 1,05 * scaling factor

9

2. If using the Windows-DLL:
Measuring value = GSVread_ pointer-content * scaling factor

The setting of the datarate and the scale factor is by using direct programming via RS232
is a little bit difficult – see above descriptions of Set Scale, Set Dpoint and
WriteSamplingFrequency.
You can save up to 6 different configurations in the EEPROM of the GSV-2 (by using the
configuration program GSV.EXE) and restore them with the command „GetAll“.

In the text format there's always one blank character (0x20) between the numerical value
and the CR/LF (even if the unit was turned off by unit-code 0x07).

Attention: After every replacement of the jumper JP1, after every change of the
datarate or changing the amplification or using other commands which affects the
analogue-digital conversion, the command „Set Cal“ must be applied.

The configuration software GSV.EXE gives the command Set Cal automatically under the
conditions mentioned.

It is recommended to use the bipolar mode rather than unipolar.

9 If you use the mode „unipolar“:
Measuring value = (Raw binary / 16777215) * 1,05 * scaling factor

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Technical Data

(At UB = 12…26V DC in the nominal temperature range)

Model GSV-2LS /

GSV-2AS

GSV-2ASD / FSD /TSD Unit /

remarks

Accuracy class

analog
digital

0.1

0.1

0.1

0.1

Measuring ranges

Analog output

Display / serial output

±1 (JP1 set to pos.1, 5V Sensorspeisung)
±2 or ±3.5 (by software and JP1 to pos.2, 2.5V sensor
supply)

0.125, 0.25, 0.50, 1.00, 2.00, 3.50 (by software)

mV/V
mV/V

mV/V

Connectable fullbridges*

4 x 350 4 x 350 Ohms

Bridge sensor supply

2,5 / 5 2,5 / 5 V

Input impedance

>20 / 300pF >20 / 300pF MOhms

Common mode rejection ratio

DC
100Hz

>120
>100

>120
>100

dB
dB

Non-linearity

<0,02 <0,02 % o.up.rang

Temperature influence on the
zero point per 10K

Messbereich 1mV/V: <0.4 typ. 0.2
Messbereich 2mV/V: <0.2 typ. 0.1

% o.up.rang
% o.up.rang

Temperature influence on the
measuring sensitivity per 10K
referred to the measured value

Analog output
Display / digital

< 0.1; typ. 0.05
<0.01; typ. 0.005

< 0.1; typ. 0.05
<0.01; typ. 0.005

%
%

Output filter Analog output

3dB cutoff frequency analog,
Bessel, 2nd order

Output filter digital

3dB cutoff frequency,

Data rate digital

3.5, 260, 1700 (by softw.)

0.06..1700

0.3125..2000

3.5, 260, 1700 (by softw.)

0.06..1700

0.3125..2000

Hz

Hz

Hz

Resolution Peak-to-peak

RMS

>30000 counts
>150000 counts

>30000 counts
>150000 counts

-->See p.60

Analog output

Usable output range at:

- Nominal range 0…10V

- Nominal range ±5V
Output resistance
Minimum load resistance

-10 ...+11

-5.5...+5.5
47
8

V
V
Ohms
kOhms

Analog input (Channel 1)

Input voltage range
Input resistance

0…10
56

0…10
56

V
kOhms

Control wires

Zero-point adjustment

Low level: <1.4 High level: >3.4

(active high)

V

Switching output

of threshold switch
Saturation voltage

200mA / 30V
<1.0

200mA / 30V
<1.0 V DC

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Model GSV-2LS /

GSV-2AS

GSV-2ASD / FSD /TSD Unit /

remarks

maximum voltage (switch off)
maximum current (switch on)
On resistance DC
Off resistance

insulation strength

60
1

0.12
10
250

60
1

0.12
10
250

V
A
Ohms
TeraOhms
V

Digital serial interface

Bit rate (dafault state)

RS 232/RS422
38400 (8N1)

RS 232/RS422
38400 (8N1) Bits/s

Supply voltage
Nominal range

Operating range

2)

9.8…30

9.8...36

9.8..30

10...36

V DC
V DC

Supply current

With display

<120 <120

<180

mA
mA

Parameter memory

Last settings,

manufacturer settings,

6 user-records

Other functions of the serial
interface

- Programmable threshold with hysteresis

- Programmable gain

- Programmable calibration of the final value (scaling
function)

- Programmable zero adjustment

Nominal temperature range
Storage temperature range

-10…+65

-40…+85

0…+50

3)

-20…+70

°C
°C

Dimensions (L x W x H)

Print board (GSV-2LS)
Housing (GSV-2AS/ASD)

125 x 53 x 30
180 x 65 x 36 180 x 65 x 40

mm
mm

Protection degree of
enclosure (DIN 40 050/IEC50(426))

IP66 IP40

1) For version LS and AS 2 further control wires optionally available

2) Temperature range and accuracy may be reduced

3) LCD with extended temperature range optionally available

Absolute maximum values

(all voltages with reference to the supply ground)

Operating voltage:
Single pulse 200ms:

-5…+42V
+100V

Differential input:

-4…+12V

Sense inputs:

-4…+12V

Control wires:

-30…+30V

Analog input:

-20…+20V

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CANbus Interface

The bus voltages are expected to be in the range from 0.5 to 4.5V (Common mode);
Withstand voltage: 0..+26V referred to CAN-GND.

CANOpen Vendor-ID

31 24 23 0

department company
00 00 02 70

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Resolution

By changing the data rate (amount of measuring values transmitted per second) the
analogue filter is changed automatically by default, as well as the filter properties of the
delta sigma A/D Converter.

Because of the internal oversampling and filtering, normally the user doesn't need to
perform extra filtering and averaging.

The charts below show measuring values with a shielded sensor cable of 1 meter, and
twisted pairs of wires, shield connected to GND. The lower the data rate is, the better is
the resolution.
Comparable results can be obtained in practice also with cable lengths of 50 meters, if the
control and the sensor-cables are installed separately and a good electromagnetic
shielding is provided.

The shielding of the RS232-interface cable should be connected to the grounding­plug of the housing.

Resolution in the measuring range „2 mV/V“ (2.5V supply voltage, JP1 in position 2)

As above, but with adaptive averaging filter enabled, see p.42

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Resolution in the measuring range „1mV/V“ (5V supply voltage, JP1 in position 1)

The peak-to-peak resolution at a data rate of 10/s is at least 30,000 counts, without
additional digital filter, if this resolution is defined as the ratio of the measuring range to
the amplitude of the peak-to-peak values, with sensor input shorted (Measuring range /
peak-to-peak deviation).
The effective resolution at a data rate of 10/s is at least 150,000 counts (measuring range
/ standard-deviation).
With the adaptive averaging filter these values increase to better results by the factor 5 –
e.g. 150,000 counts peak-to-peak resolution at 10Hz. This is valid with suitably adjusted
filter only (see p.42).

More informations http://www.me-systeme.de/gsv2-dat.html#resolution

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Description of the jumpers / selectors

JP1: Changing the bridge supply voltage:

position 1 (left): bridge supply voltage = 5V, input sensitivity = 1mV/V
position 2 (right): bridge supply voltage = 2.5V, input sensitivity = 2 or 3.5mV/V
(see Set/Get Range) Attention: the jumper has to be plugged!

JP2: Configuration mode for baudrate and protocol settings
Set: Configuration mode is enabled, Baudrate is fixed to 38400 Bits/s
Not set: Configuration mode is disabled, the baudrate of the baudrate-register is valid
(see Set /Get Baud)

JP3: Change the serial interface from RS232 (V24) to RS422:
set: RS422 (4 wires). Not set: RS232 (V24), state at delivery

Connector pin assignment RS232: A: GND, B: RX, C: TX
Connector pin assignment RS422: A: GND, B: RX-, C: TX-, D: RX+, E: TX+

Dimensions of the circuit board GSV-2L

ME-Meßsysteme GmbH, Neuendorfstr. 18a, D-16761 Hennigsdorf

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Dimensions of the aluminium housing of the GSV-2AS

ME-Meßsysteme GmbH, Neuendorfstr. 18a, D-16761 Hennigsdorf Germany

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Front panel cut out and housing of the GSV-2FSD

Dimensions of the GSV-2TSD-DI

L x B x H: 200 x 175 x 75 mm

ME-Meßsysteme GmbH, Neuendorfstr. 18a, D-16761 Hennigsdorf

64 Phone [phone], Fax [phone], [e-mail] , www.me-systeme.de/en

138

68

6

0

Zero

+1,0

+0,7

Subject to change without notice.
Every information describes the product in general.
They are no assurance of features in the sense of §459 Abs. 2, BGB (German civil code)
and assume no liability.

Made in Germany Copyright  1999-2012