AST BA 662 User manual

Technical changes reserved. 09/2016 Page 1 of 10
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik
Strain Gauge Measuring Amplifier BA 662
Original of the
Manual
Table of Contents
1.Safety precautions ........................................................................................................... 2 
1.1.Field of application ....................................................................................................... 2
1.2.Installation ................................................................................................................... 2
1.3.Maintenance ................................................................................................................ 2
2.Function ............................................................................................................................ 2
3.Specifications ................................................................................................................... 3
3.1.General technical data ................................................................................................. 3
3.2.Circuit diagram ............................................................................................................ 4
3.3.Dimensions .................................................................................................................. 4
3.4.Connections ................................................................................................................ 5
3.5.How to connect signal output ...................................................................................... 5
3.6.Trigger input ................................................................................................................ 5 
4.Operation .......................................................................................................................... 6
4.1.Overview operating elements BA662/IP20 .................................................................. 6
4.2.How to operate the keys .............................................................................................. 6
4.3.Amplification ................................................................................................................ 6 
4.4.Zero alingment ............................................................................................................ 7
4.5.Filter ............................................................................................................................ 7
4.6.Signal output ............................................................................................................... 7
4.7.LED Status .................................................................................................................. 8
4.8.Restart ......................................................................................................................... 8
4.9.Factory setting (RESET) .............................................................................................. 8
5.Using the Software ASTAS (USB) ................................................................................... 8
6.EC Declaration of Conformity ......................................................................................... 9

Manual BA 662
Page 2 of 10 Technical changes reserved. 09/2016
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik
1. Safety precautions
In this operating manual, the installation, putting into operation and the operation itself of the
Strain Gauge Bridge Amplifier BA 662 is described. It is assumed that all measures are taken
by qualified staff only who have adequate knowledge in the fields of measuring and control
engineering.
ATTENTION! Any non-compliance with these safety precautions may result in
severe damage to property and health.
1.1. Field of application
The Strain Gauge Bridge Amplifier BA 662 has been designed to the purpose of amplifying the
output signals of sensors with metal-foil strain gauges, preferably force transducers and
transform them into standard signals. Any other application is regarded contrary to the
intended purpose. The manufacturer does not accept any liability for damages resulting from
such inappropriate usage. In this case it is the user alone who has to bear the risk.
Type BA 662 must not be used as the sole means to prevent dangerous conditions of
machines and plants. All machines and plants must be constructed in such a way (e.g. by
using mechanical stops, limit switches) that a condition of failure does not result in a situation
of severe danger.
It must be made sure that any erroneous setting or malfunction of the unit or its breakdown
cannot cause damage or be a risk to the operating staff or other persons.
1.2. Installation
The unit must be installed and connected in compliance with the current DIN- and VDE-
standards. Supply cables and signal lines shall be installed so that interference signals such as
electrical interference do not have any adverse effects on the function of the equipment.
1.3. Maintenance
The device does not contain any components that require maintenance. Repairs shall be
carried out by the manufacturer only.
2. Function
The Strain Gauge Bridge Amplifier BA 662 is a digital amplifier for the low-drift amplification of
the output signals of sensors with metal-foil strain gauges, preferably force transducers to
supply a standard signal of (-10/0...10) VDC or (0/4...20) mA.
An internal voltage source provides the stabilized feeding voltage for the sensor. The power is
supplied by an unstabilized source of (9...36) VDC. The Strain Gauge Bridge Amplifier is
delivered in a case for standard rails in accordance with DIN EN 50022-35.
The BA 662 is delivered with a factory setting for an input signal of 2mV/V and a corresponding
output signal of ± 10V or 20mA. The other input signal ranges 0.1mV/V to 7mV/V can be
generated internally from the 2mV/V factory adjustments. The different settings of the factory
adjustments (zero point and gain) can be changed by the user through keys.
By an optically separated input, the zero-setting can be carried out by means of a superior
control and through the trigger input. The overload limit is not affected by such a zeroing, which
means that 100 % of the end-value adjustment of the sensor remains as end value. An existing
preload by a container can thus be set zero.

Manual BA 662
Technical changes reserved. 09/2016 Page 3 of 10
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik
3. Specifications
3.1. General technical data
*Software - Download over www.ast.de
Class of accuracy at input signal
2mV/V % FSR < 0.02 (typ.)
Connection for strain gauge sensor 4- or 6-wire
Bridge resistance / range of input
impedance
Input signal range (+Si/-Si)
Excitation voltage (+Ex/-Ex)
Ω
mV/V
VDC
58...2000 (up to 6 loadcells each 350 Ω)
0.1 / 0.25 / 0.5 / 1.0 / 1.5 / 2.0 / 3.0 / 4.0 / 5.0 /
7.0
±2.5
Norm Output
Current Output
Voltage Output
Load resistance
mA
V
Ω
0/ 4... +20; 0…24
≤ 500
-10/-5...0…+5/ +10
≥ 1000
Measurement Characteristics
Conversion rate Hz 6 …. 3200
Resolution of the A/D Converter Bit 24
Filter Hz 0.8…2000
Error at S=2mV/V
Nonlinearity
Noise (at measurement rate)
Input sensitivity for 1 LSB
Zero drift
%FSR
%FSR
nV
%/ 10K
0.0025
0.002 (0.8Hz) … 0.009 (2000Hz)
150
<0.01
Power Supply
Input range
Power consumption (without sensor)
VDC
W
9 ... 36
1
Environmental Conditions
Operating temperature range
Storage temperature range
°C
°C
- 20...+ 60
- 25...+ 85
Construction Plastic housing for DIN-rail mounting
Weight
Dimensions (W x H x D)
Environmental protection (EN 50529)
Terminal block, wire size
kg
mm
mm²
0.2
22.5 x 114.5 x 99
IP 20
0.14 … 2.5

Manual BA 662
Page 4 of 10 Technical changes reserved. 09/2016
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik
3.2. Circuit diagram
+Se
+Ex
+Si
-
Si
-
Ex
-
Se
A
D
C
μC
Power supply
16-Bit
-DAC
±12V
DIP - Switcher
(
Config . DAC )
AG
V Out
I Out
9 ... 36VDC
0V
1.Stab
Filter
2.Stab
2’. Stab
Shi
EMC-Filter
Output
Sensor
T
+ 24VDC
T
- 0V
USB:
(ASTAS*, Configuration DAC, Filter)
3.3. Dimensions
AG
+Si -Si
24V
-Ex +Ex
V
OUT
I
OUT
0V
-Se +Se
Tr-
NC
NC SHI
Tr+
Output
0 ... 10V
0 ... 5V
-10 ... +10V
-5 ... +5V
0 ... 20mA
0 ... 24mA
4 ... 20mA
Filter (Hz)
0,8
156
8,3
2000
1315
625
38567
25
2,4
99
2
2
,5
114,5
6-Wire
4-Wire
100%
0%
mV/V
+
+
-
-
Status
BA 662
0.1 2.0
0.5
0.25 1.5
1.0
3.0
4.05.0
7.0
Reset USB

Manual BA 662
Technical changes reserved. 09/2016 Page 5 of 10
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik
3.4. Connections
Installation recommendations
 Use shielded cables.
 Use the largest possible cable cross section (Error due to cable extension).
 Lay the measuring lines separately from the power supply lines.
 At the force transducers and the measuring amplifier, make as short as possible a
connection to earth, in particular in strong electromagnetic fields.
 Additionally, lay an equipotential bonding parallel to the measuring line.
 Keep away from stray fields of motors, transformers and contactors.
 Connect force transducers, amplifier, mains unit, and indicator / processor unit with earth in
one place only.
 Set the slide switch for the sensing line (6- or 4-wire) according to the sensor connection.
3.5. How to connect signal output
The Bridge Amplifier BA 662 provides different output signals, depending upon the setting of
the slide switches. (see 4.6)
NOTE Either the current output or the voltage output can be used, not both at the
same time.
TIP: o form the sum, current outputs of several BA662 can be connected in parallel. In
this case, 12V should not be exceeded at the standard output and the maximum load
(load resistance) be <12V / IOut .Voltage outputs must not be connected in parallel.
3.6. Trigger input
The BA662 has an optically separate trigger input so that the zero-setting can be carried out by
means of a superior control. The overload limit is not affected by such a zeroing.
The function is started by a 24 VDC trigger impulse.
Note! The measuring amplifier is protected against reverse polarity.
Terminal connection Description
-Ex neg. Exitation voltage
Sensor with
6-wire
-Se neg. Sense signal
+Se pos. Sense signal
+Ex pos. Exitation voltage
+Si pos. Signal
-Si neg. Signal
NC not connected
SHI Shield
AG Ground for output signal
Outuput signal
Vout Voltage output
Iout Current output
NC not connected
24V Supply voltage Power supply
0V Supply voltage ground
Tr+ Trigger 24V electrically isolated input
Tr- Trigger 0V

Manual BA 662
Page 6 of 10 Technical changes reserved. 09/2016
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik
4. Operation
4.1. Overview operating elements BA662/IP20
Sensitivity/
measuring range
of sensor in mV/V
Connection
Zero:
Push simultaneous:
Zero calibration
Amplification
Push simultaneous:
Load calibration
LED: Status
Factory setting
(RESET)
6-Wire
4-Wire
100%
0%
mV/V
+
+
-
-
Status
BA 662
0.1 2.0
0.5
0.25 1.5
1.0
3.0
4.05.0
7.0
Reset USB
Output
0 ... 10V
0 ... 5V
-10 ... +10V
-5 ... +5V
0 ... 20mA
0 ... 24mA
4 ... 20mA
Filter (Hz)
0,8
156
8,3
2000
1315
625
385
67
25
2,4
4.2. How to operate the keys
Keys individually / short: Setting of the signal output
Keys individually / long (2s): Fast setting of the signal output
4.3. Amplification
Switch position 0 1 2 3 4 5 6 7 8 9
Measuring range (mV/V) 0,1 0,25 0,5 1,0 1,5 2,0 3,0 4,0 5,0 7,0
>100% +< and >100% -< simultaneously (2s):
Adjustment of the present input signal (currently applied force) to100% of the output signal
(end-value adjustment).
By individually pushing the keys >100% +< or >100% -< respectively, an individual fine
adjustment of the output signal / the end value is possible.
NOTE In case of changing the amplifier output by means of keys > 100 % +< or >
100% -< there should always be a zero-alignment check.
NOTE Amplification-values are saved permanently 7 seconds after last push button
action. During saving LED blinks for a short time.

Manual BA 662
Technical changes reserved. 09/2016 Page 7 of 10
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik
0 … +10V
0 … + 5V
-10 … +10V
-5 … + 5V
0 … 20mA
0 … 24mA
4 … 24mA
4.4. Zero alingment
>0% + < and >0% - < simultaneously (2s):
Setting of the present input signal at the output to zero point (zero-adjustment/ zero-alignment)
By individually pressing the keys >0% +< or >0% -< respectively, an individual fine adjustment
of the output signal / the zero point is possible.
NOTE! Zero-values are saved permanently 7 seconds after last push button action.
During saving LED blinks red for a short time.
4.5. Filter
Through a low-pass filter, the output signal can be set in 10 stages, from 0.8 to 2000Hz.
Filter (Hz) 0,8 2,4 8,3 25 67 156 385 625 1315 2000
Internal Sample rate (Hz) 6 12 25 50 100 200 400 800 1600 3200
4.6. Signal output
DIP-switch explanation: DIP-switch function:
ATTENTION! In case of exceedance of the input signal of >-120%, the analogue
output is set to the maximum positive initial value.
In case the input signal lies in the range between -120% and 0%, the minimum
analogue signal is released at the unipolar voltage output and the current output
respectively (see too 4.7).
Input
o utput bipolar (U)
120% - 120%
Input
Sensor mV/V
o utput unipolar (U/I)
- 120% 120%
Graph 1
Output signal in case of error (bipolar)
Output signal -5…5V, -10…10V
Graph 2
Output signal in case of error (unipolar)
Output signal 0…5/10V, 0/4…20/24mA
3 2 1
- OFF -

Manual BA 662
Page 8 of 10 Technical changes reserved. 09/2016
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik
4.7. LED Status
LED display Explanation Error description
Green Ready for operation  No error
Red 1 x flashing ADC-Overload
 Error at connections of sensor lines
 Cable break in sensor line
 Switch for 6- and 4-wire not accordingly
connected
Red 2x flashing Indicates overload
or underload
 Exceed of maximum load of 120% of nominal
sensitivity, or exceed minimum load (see too 4.6)
Red 3x flashing TEDS error
 Error in the memory of the automatic sensor
recognition
 (only option with TEDS)
Red 4 x flashing Output > 100%  The amplification at the output is set too high.
Red 5 x flashing Current output open
or overheating DAC
 Output side not closed
 Cable break at output
 Thermal overheating - cooling necessary
Red 6 x flashing Hardware error  General error – restart necessary
4.8. Restart
100% - and >0% +< simultaneously: A restart is carried out. All settings are saved.
4.9. Factory setting (RESET)
For all ten sensitivity settings / measuring ranges (see 4.1 – sensitivity in mV/V of the sensor)
factory settings are stored in the amplifier.
Individual adjustments of the amplification (see 4.3.) or of the zero point (see 4.4) carried out
later by the user, do only influence the active measuring range that has just been set.
When simultaneously pushing the two keys >100% +< and >0% -< for 2s, all zero-point
adjustments and end-value adjustments of all ten measuring ranges are deleted and reset to
the factory settings of 0mV/V ≙ initial value of the selected signal output (-5/-10/0V or 0/4mA)
and 2mV/V ≙ end value of the selected signal output (5/10V or 20/24mA).
NOTE! After reset to factory settings, the amplifier has to be newly adjusted to the
sensor!
5. Using the Software ASTAS (USB)
Load the software from our website www.ast.de
TIP: Linearization: If the measured values between zero and rated load should
deviate from the real load, up to four additional points can be set to increase the
measurement accuracy. These measuring points can be made in any order, similar to
the input of the zero point and end point. After entering all of the calibration points, the
result must be stored.

Manual BA 662
Technical changes reserved. 09/2016 Page 9 of 10
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik
6. EC Declaration of Conformity

Manual BA 662
Page 10 of 10 Technical changes reserved. 09/2016
A.S.T. - Angewandte System Technik GmbH, Mess- und Regeltechnik