HBM AED9301B User manual

User Manual
AED9301B
Digital Transducer Electronics
Basic Device PROFIBUS
I1694-2.0 en

Content 1
AED9301B HBM
Content
Typographical conventions................................................................................................3
Important information.........................................................................................................4
Safety instructions..............................................................................................................5
1Introduction and appropriate use......................................................................................6
2Mechanical construction....................................................................................................7
3Electrical connections........................................................................................................8
3.1 Transducer connection......................................................................................................................... 8
3.2 Connecting the supply voltage.............................................................................................................13
3.3 Profibus connection.............................................................................................................................14
3.4 Connecting digital inputs/outputs.........................................................................................................16
3.5 Connecting the diagnostic bus.............................................................................................................21
3.6 AED9301B cable connection via PG glands ........................................................................................23
Index...................................................................................................................................24

2
HBM AED9301B

Typographical conventions
AED9301B HBM
3
Typographical conventions
For clear identification and improved legibility, the following conventions have been used in
this documentation:
Important paragraphs are marked with a symbol to draw attention to them.
CE Designation
Statutory marking requirements for waste disposal
Italics Points out external documents and files
“File Open“ All menus and menu commands appear in quotes, here the “File” menu and the “Open” sub-
menu.
“Start” Quotes and italics are used for buttons, input fields and user input.
MSV All commands are set out in a bold font style or as a link to the command description.

4Important information
HBM AED9301B
Important information
Neither the design of the device nor any technical safety aspects may be modified without the
express permission of Hottinger Baldwin Messtechnik GmbH. Any modification excludes Hot-
tinger Baldwin Messtechnik GmbH from any and all liability for any damage resulting there-
from.
It is strictly forbidden to carry out any repairs and soldering work on the motherboards or
to replace any components. Repairs may only be carried out by persons authorized
thereto by Hottinger Baldwin Messtechnik GmbH.
All the factory defaults are stored safe from power failure at the factory, not in the measuring
amplifier where they can be deleted or overwritten. They can be reset at any time by using the
command TDD0. For more information, see aed_help_e AD103C; “Description of the basic
commands”.
The production number is set at the factory and cannot be changed.
The transducer connection must always be assigned.
It is essential for a transducer or a bridge model to be connected up for operation.

Safety instructions 5
AED9301B HBM
Safety instructions
 There are not normally any hazards associated with the product, provided the notes and
instructions for project planning, assembly, appropriate operation and maintenance are
observed.
 Each time, before starting up the modules, you must first run a project planning and risk
analysis that takes into account all the safety aspects of automation technology. This
particularly concerns personal and machine protection.
 It is essential to comply with the safety and accident prevention regulations applicable to
each individual case.
 Installation and start-up must only be carried out by suitably qualified personnel.
 Do not allow the equipment to become dirty or damp.
 During installation and when connecting the cables, take action to prevent electrostatic
discharge as this may damage the electronics.
 The required power supply is an extra-low voltage with safe disconnection from the
mains.
 When connecting additional devices, comply with the local safety requirements.
 All the interconnecting cables must be shielded cables. The screen must be connected
extensively to ground on both sides.
The power supply and digital I/O connection cables only need to be shielded if the ca-
bles are longer than 30 m (32.81 yd) or are routed outside closed buildings.
 The CE mark enables the manufacturer to guarantee that the product complies with the
requirements of the relevant EC directives (the declaration of conformity is available at
http://www.hbm.com/HBMdoc).
 In accordance with national and local environmental protection and material recovery
and recycling regulations, old devices that can no longer be used must be disposed of
separately and not with normal household garbage.
If you need more information about waste disposal, please contact your local authorities
or the dealer from whom you purchased the product.

6Introduction and appropriate use
HBM AED9301B
1Introduction and appropriate use
AED9301B digital transducer electronics are part of the AED component family that digitally
conditions signals from mechanical measurement sensors and networks them with bus ca-
pability. These include digital amplifier motherboards, basic devices with serial interfaces
and intelligent sensors with integrated signal processing. The purpose of these components
is to directly digitize and condition the measurement signals at the transducer location.
Using AED9301B digital transducer electronics, you can connect SG1) transducers in a full-
bridge circuit directly to a Profibus DP. This enables you to connect complete measurement
chains to a field bus quickly and with little extra work.
The AED9301B basic device can contain the AD103C measuring amplifier board. It provides
mechanical protection, shields the amplifier board (EMC protection) and allows a Profibus
connection and implements full electrical isolation of all connections.
The AD103C amplifier motherboard is not included in the scope of supply of the basic de-
vice.
Two digital inputs and four digital outputs allow:
 processes to be controlled via four limit values (LIV1…4),
 triggered measured values to be determined (MAV) and
 a filling or dosing process to be controlled.
The PC software AED PANEL 32 is available to facilitate parameter settings, to display dy-
namic measurement signals and for comprehensive analysis of the dynamic system.
The HBM display unit DWS2103 can be connected to all AED basic devices.
All basic devices of the AED family can be connected with the digital display unit DWS2103.
This unit supports all implemented functions of the AED.
The Profibus communication is described in the file aed_help_e, AED9301B; “Description of
the Profibus communication” .
All commands are described in the help file aed_help_e.
The abbreviation AED is also used for AD103C transducer electronics in the following text.
1) Strain Gage

Mechanical construction 7
AED9301B HBM
2Mechanical construction
The basic device extends the functionality of the AD amplifier boards and provides:
 mechanical protection (IP65)
 a slot for the AD103C amplifier board
 the power supply for the amplifier motherboard and transducer excitation (electrically iso-
lated)
 total transducer bridge resistance 80 ...4000 
 a Profibus DP interface (electrically isolated from the amplifier and from the digital inputs
/outputs)
 digital inputs/outputs (electrically isolated from the amplifier and from the Profibus)
 EMC protection
 Diagnostic bus
The amplifier motherboard (AD103C) is designed as a plug-in board that can be plugged into
the carrier board of the basic device via a 25-pin sub-D connector. The basic device contains
terminals for the transducer, power pack, digital inputs/outputs and Profibus connections,
slide switches for bus disconnection and termination resistor connection and the voltage sta-
bilizer. The connection cables exit the casing via PG glands on the side.
Fig. 2-1: Mechanical construction AED9301B (without amplifier)

8Electrical connections
HBM AED9301B
3Electrical connections
The AED9301B basic device comes with a connection diagram.
When making the connections, please ensure that the wires of the cable do not protrude
beyond the connection terminals (risk that loops may form). Please make sure that the
cable shielding is properly connected to the PG gland (see the AED9301B cable connec-
tion via PG glands section).
If it should be necessary, a separate cable can be used to establish potential equalization
between the transducer and the AED and between the AED and the Master control unit
(grounding concept). The cable shielding must not be used for this potential equalization.
3.1 Transducer connection
The transducer connection must always be assigned (connect the transducer).
Fig. 3.1-1: Transducer connection in 6-wire circuitry (HBM color-coding)

Transducer connection 9
AED9301B HBM
You can connect SG transducers in afull-bridge circuit with a total bridge resistance of
RB= 80...4000 . With a transducer resistance of >1000 , increased noise (measurement
ripple) must be taken into account.
The bridges are supplied with power in the AED9301B basic device at 5 VDC.
The 6-wire connection avoids the effect of a long cable on the measured value. When sev-
eral transducers and a junction box are used, the 6-wire circuitry is routed to the junction
box.
Fig. 3.1-2.: Transducer connection in the AED9301B basic device for a 6-wire connection
There are two methods of connection for transducers implemented in four-wire circuitry:
 Connection via a 6-core extension cable; bridged sensor circuit in the transducer con-
nector (connect terminals 3 and 3’ and 2 and 2’).
 Connection without an extension cable; sensor circuit bridged at the transducer electron-
ics (connect terminals 3 and 3’ and 2 and 2’).

10 Transducer connection
HBM AED9301B
Plug-in connection
Cable to
transducer electronics
Transducer bu
rd
wh
bk
bu
gn
wh
gy
bk
Cable shield
Fig. 3.1-3: Transducer connection in 4-wire circuitry via a 6-core cable extension
When connecting several transducers, it is advisable to use an HBM junction box VKKx. In
general, the feed lines running to the AED should be shielded cables.
Notes on type of connection, length and cross-section of cables:
Depending on the bridge resistance of the load cell being used and the length and cross-
section of the load cell connection cable, there may be voltage drops that can reduce the
bridge excitation voltage.The voltage drop at the connection cable is also dependent on tem-
perature (copper resistance). Likewise, the output signal of the load cell changes in propor-
tion to the bridge excitation voltage.
Effect on the measurement result with the internal Auto calibration function:
Auto calibration safeguards the measurement accuracy of the measuring amplifiers (see
“Hardware and Functions” of the AD103C).

Transducer connection 11
AED9301B HBM
6-wire circuit (standard mode of operation):
This will correct all the effects of the load cell cabling up to the feedback points. Even chang-
ing the length of a cable after calibration will not make any difference to the measurement
results.
For load cells with a 6-wire connection, feedback lines 2´ and 3´ are bridged in the load cell
with excitation 2 and 3 (Fig. 3.1-2). For load cells with a 4-wire connection, the feedback
bridges must be implemented directly at the load cell connection (Fig. 3.1-3).
4-wire circuit:
As correction through AUTOCAL can only ever take place up to feedback points 2´, 3´, all
the changes of cable resistances affect the measurement result. This means that even if no
further changes are made to the 4-wire cable used for calibration, there will still be meas-
urement errors when there are temperature changes, because the cable resistance and pos-
sibly the contact resistances at the connectors are temperature-dependent. With the 4-wire
circuit, feedback lines 2´ and 3´ are directly connected at connection terminals 2 and 3 in the
AED (see Fig. 3.1-4).
Equivalent circuit of the bridge with bridge resistance RBand supply lines with
line resistances RL1 and RL2:
The voltage drop over the bridge feeder cables can be determined from bridge resistance
RB, cable length l, cable cross-section A and the bridge excitation voltage:
UB+ URL1 + URL2 = UBR

12 Transducer connection
HBM AED9301B
For
RB= 80 , RL1 = RL2 = 1.6 (l = 10 m) and UBR = 5 V
there is an excitation current of
IBR = UBR / (RL1 + RL2 + RB) = 60 mA
and thus a voltage drop over the two line resistances totaling approx. 0.2 V
(UBridge = 4.8 V).
For
RB= 80 , RL1 = RL2 = 16 (l = 100 m) and UBR = 5 V
there is an excitation current of
IBR = UBR / (RL1 + RL2 + RB) = 45 mA
and thus a voltage drop over the two line resistances totaling approx. 1.4 V
(UBridge = 3.6 V).
This is irrelevant for the 6-wire circuit, as the voltage drop over the sensor lines is taken into
account in the measurement signal.
But with a 4-wire circuit, the dependency of the copper resistance of the cables on tempera-
ture goes directly into the measurement result, as the bridge excitation voltage UBridge
changes:
RL(t) = RL20 (1 +   (t – 20 °C)),
where RL20 is the line resistance at 20 °C and  is the temperature coefficient of the cop-
per.
RL20 –calculation see page 10, CU = 0.00392 [1/K]
With a cable length of l = 109.36 yd and a temperature differential of 10°C, there is a line re-
sistance of
RL1(t) = RL2(t) = 16 (1 + 0.00392 10) = 16.6 
This changes the bridge excitation voltage of
UBridge = 3.6 V (at 20 °C) to UBridge = 3.53 V.
This change in bridge excitation voltage directly at the transducer changes the measurement
signal of the bridge by 2 % (= 100 % (1 – 3.53 V / 3.6 V)).
This typical calculation shows that if long cables are involved, only 6-wire circuitry should be
used.

Connecting the supply voltage 13
AED9301B HBM
3.2 Connecting the supply voltage
The power supply must meet the following requirements:
AED9301B DC voltage +18 V...+30 V
Current consumption 200 mA + current of control outputs OUT1...4
(at 80 bridge resistance and 24 V power)
Calculating total current consumption (at 80 bridge):
Current consumption for 18 V power supply: 250 mA + IOUT 1...4
Current consumption for 24 V power supply: 200 mA + IOUT 1...4
Current consumption for 30 V power supply: 170 mA + IOUT 1...4
IOUT 1...4 = control outputs current
Fig. 3.2-1: Power supply connection
The AED supply voltage can be connected at terminals KL1 and KL2. The three ground ter-
minals and the two voltage terminals are each interconnected internally. The supply voltage
coming from the power pack is connected at terminal KL1; this supply voltage can be routed
to other devices at terminal KL2.
Electrically isolated digital outputs OUT1...OUT4 are also supplied from this voltage. The po-
tential separation occurs in the AED direction. Consequently the units controlled from
OUT1...4 can also be fed from UB(see Connection of digital inputs/outputs).
Control inputs IN1 and IN2 are initially electrically isolated from supply voltage UB. The two
grounds (ground UBand ground IN) can be connected to terminal KL1, if required (see Con-
nection of digital inputs/outputs).

14 Profibus connection
HBM AED9301B
3.3 Profibus connection
Profibus DP is fully standardized to IEC61158 / EN50170 for universal automation, so there
is no difficulty in connecting components that conform to the standard.
In the case of the AED9301B, this is a Profibus DP Slave in accordance with DIN19245-3. It
provides a simple and quickly implemented option for connecting electromechanical meas-
urement sensors to automation systems such as SIEMENS SIMATIC S7 or to PCs.
The Profibus is electrically isolated from the measuring system and from the supply voltage,
the transmission procedure is RS485. The maximum possible baud rate for RS485 is
12 Mbit/s. The node address can be set via two BCD-coded rotary switches “S5” and “S4”.
The Profibus connection KL3 is equipped with four terminals, so that it can be routed to the
next bus node. The connection cables should be shielded, twisted-pair cables (see Profibus
cable specification).
Bus termination should be activated at both ends of the Profibus line (at the AED switch
“S2 = on”). This switch must be set to “off” for all the other bus nodes. The module can be
disconnected from Profibus for diagnostic purposes (“S3 = off”). The factory default for this is
on.
Profibus
Bus termination
Profibus
Bus link
from Master next device
Adress settings
Fig. 3.3-1: Profibus connection via terminal KL3

Profibus connection 15
AED9301B HBM
Maximum cable length subject to bit rate:
Bit rate [kbit/s] 9.6 19.2 93.75 187.5 500 1500 12000
Max. cable length [m] 1200 1200 1200 1000 400 200 100
Setting the Profibus address
Address = S5 10 + S4 (permissible address range: 3...99)
The address must be set in the deactivated state and read in by the AED when the supply
voltage is applied. The address is set to 03 at the factory.
Light-emitting diode functions (LEDs)
The various Profibus states are indicated by 4 LEDs (Fig. 2-1):
LED1: Profibus power supply (green, on the right next to the bus termination)
the RS485 driver supply voltage is being applied if LED 1 shows a continuous
green light
LED2: Profibus Data Exchange (green)
The Data Exchange state is indicated for cyclic data communication by green
LED 2.
LED3: Profibus diagnostics (yellow)
The yellow LED 3 comes on when there is an internal error. The measurement
data may be invalid.
LED4: Profibus error (red)
When there is a bus error, LED 4 shows red and stays on as long as the error
persists.
Possible causes:
-Incorrect wiring (A and B may be transposed)
-Profibus Master not (yet) working

16 Connecting digital inputs/outputs
HBM AED9301B
Installing Profibus:
1. Connect the feed lines in the deactivated state to the AED (see Electrical connection
section). The Profibus line is routed from one device to the next via KL3.
2. Use “S5” and “S4” to set the node address.
3. Set the switch for connecting bus termination (“S2”):
Caution: Only set it to on for the first and last device, otherwise leave in the off position.
If the first or last bus node is not an AED, you can usually connect bus termination via a
slide switch on the Profibus connector housing.
4. Check that the bus link switch (“S3”) is set to on.
5. Activate supply voltage UB.
6. Use the relevant tools to configure and assign parameters to the Profibus node.
Configuration and parameter assignment of the Profibus message with a configuration tool
and GSD file is described in the aed_help_e, AD9301A; “Description of the Profibus commu-
nication”. Also the linking the bus via a PC and the HBM Profibus Panel program.
The Profibus can be separated from the AED for diagnostic purposes (bus link (S3) to “off”).
3.4 Connecting digital inputs/outputs
At terminals KL1 and KL2 are the digital control inputs and control outputs together with the
associated ground references.
The measuring amplifier is always electrically isolated from external supply voltage UBand
from the digital inputs and outputs

Connecting digital inputs/outputs 17
AED9301B HBM
control inputs
Control inputs IN1 and IN2 are initially electrically isolated from supply voltage UBand from
the measuring ground, the reference potential is ground IN at terminal KL1 on the right next
to the inputs.
Fig. 3.4-1: Connection of digital I/Os, inputs and external power pack 1 electrically isolated
Logic level:
IN1: Trigger: quiescent level = low, active edge = high-low edge
Break Dosing: quiescent level = low, activation = low-high-low-Puls
(duration 20 ms)
IN2: Taring or
Start dosing quiescent level = low, activation = low-high-low-Puls
(duration 20 ms)
Unused inputs remain open. If the input circuit is also supplied via UB, the ground of the
inputs and the ground of the UBmust be connected.

18 Connecting digital inputs/outputs
HBM AED9301B
Fig. 3.4-2: Connection of digital inputs and outputs, inputs and external power pack not electrically
isolated (IN1 = trigger)
Control outputs:
Digital outputs OUT1…4 are electrically isolated and are supplied via external supply voltage
UB. They are implemented as High side switches. Consequently, consumers must be con-
nected to ground. The outputs are short-circuit-proof and can drive ohmic and inductive
loads with currents up to approx. 0.5 A per output.
Logic level: OUT inaktiv  voltage is Low (H-side switches deactivated)
OUT aktiv voltage is High (H-side switches activated)
The functions of the digital inputs and outputs differ in accordance with the type of measuring
amplifier used (basic, plus)