Flintec FAD-4 User Manual
FAD-4
ANALOGUE LOADCELL JUNCTION BOX
WITH TRANSDUCERS ELECTRONICS
REFERENCE MANUAL
Flintec GmbH
Bemannsbruch 9
74909 Meckesheim
Germany
Tel. +49 6226 92400
Fax. +49 6226 924099
www.flintec.net
germany@flintec.net
FLINTEC
Document
FAD - 4 DIGITAL LOADCELL JUNCTION BOX
Date
02.05.00 FAD4_2RM
Code
Rev.
2
Page
1 of 20
FLINTEC
TABLE OF CONTENTS
1 INTRODUCTION........................................................................................................................................... 3
2 HARDWARE DESCRIPTION – INSTALLATION ...................................................................................... 4
2.1 Mounting.................................................................................................................................................. 4
2.2 Wiring ...................................................................................................................................................... 4
2.3 Power........................................................................................................................................................ 4
2.4 Analogue output........................................................................................................................................ 4
2.5 Setpoint outputs........................................................................................................................................ 4
2.6 Tilt switch................................................................................................................................................. 4
3 FUNCTIONAL DESCRIPTION..................................................................................................................... 5
4 SETUP & CALIBRATION SEQUENCE..................................................................................................... 14
5 CALIBRATION EXAMPLES ...................................................................................................................... 15
5.1 STANDARD (WEIGHTS)..................................................................................................................... 15
5.2 ELECTRONIC (mV/V). ........................................................................................................................ 16
6 OPERATION ................................................................................................................................................ 17
7 ERRORS ....................................................................................................................................................... 18
8 SPECIFICATIONS - MAINTENANCE....................................................................................................... 19
8.1 TECHNICAL SPECIFICATIONS......................................................................................................... 19
8.2 ENVIRONMENTAL CONSIDERATIONS.......................................................................................... 20
8.3 MAINTENANCE................................................................................................................................... 20
8.4 SERVICE ............................................................................................................................................... 20
This manual contains proprietary information, protected by international copyright lows. No part of this
document may be reproduced without the written agreement of the publisher, Flintec GmbH.
The information herein is believed to be both accurate and reliable. Flintec GmbH however, would
be obliged to be informed if any errors occur. Flintec GmbH cannot accept any liability for direct or
indirect damages resulting from the use of this manual.
Flintec GmbH reserves the right to revise this manual and alter its content without notification at any time.
Document
FAD - 4 DIGITAL LOADCELL JUNCTION BOX
Date
02.05.00 FAD4_2RM
Code
Rev.
2
Page
2 of 20
FLINTEC
1 INTRODUCTION
The FAD-4 is a junction board for connection of up to 4 analogue loadcells. It contains all transducer
electronics to excite the strain gauges, amplify, filter and convert the analogue signal of each loadcell to a
digital form. The outputs from each loadcell are corner corrected and summed to form the scale weight
output. If one loadcell is connected only it should be connected to LC.1 input, two loadcells to inputs 1
and 2 etc.
The weight is output in digital form via an RS485A serial interface or in analogue form via a
0 , 4 – 20mA optional interface.The RS485 interface may be used in multidrop applications where each
FAD-4 has itsown unique address.
All weighing functions necessary for operation of weighing system such as Zero, Tare, No motion
detection, error monitoring are performed by the FAD-4.
An ASCII standard serial interface command set allows FAD-4 to be connected with personal computers,
PLCs ,intelligent peripherals, etc.
The calibration of each corner and of the scale is handled by the FAD-4 through a calibration sequence
initiated via the serial interface. Calibration constants are stored in EEPROM on board.
Calibration sequrity is effected by a CALLOCK hardware inside the DJB which may be sealed and a
PINLOCK software device that once activated inhibits access to calibration constants if the PIN code is
not entered. The unit is also provided with an Audit Trail Counter which is incremented every time the
calibration parameters and / or constants are modified.
The weight data rate is setup selectable to cater for high accuracy static weighing (2-5 conversions/sec) or
medium accuracy dynamic weighing (10-20-40 conversions/sec) applications with computers or other
systems.
The unit has been designed for use in industrial environments and is EMC compliant to EN 45501 standards.
The FAD-4 has two optoisolated setpoint outputs and one optoisolated input. It also has a serial display
and keyboard interface plus a multiprocessor interface at TTL level.
A potential free Tilt switch may be connected to inhibit weighing while the scale is not level.
OPTIONS
OP.1 Analogue output 20mA optoisolated.
OP.2 Automatic Tilt correction device (Two directional).
OP.3 PCLINK software to link to higher level software (DOS or WINDOWS environment).
OP.4 Stainless steel housing 200 x 105 x 45 mm with cable glands or DB9F connector.
OP.5 Mains power adapter 230 VAC to 9 VAC/ 500mA.
OP.6 Remote Display Terminal RDT-52.
OP.7 RS232C/RS485A converter including power adapter 230 VAC to 9 VAC/ 500mA.
OP.9 Custom software on request.
Document
FAD - 4 DIGITAL LOADCELL JUNCTION BOX
Date
02.05.00 FAD4_2RM
Code
Rev.
2
Page
3 of 20
FLINTEC
2 HARDWARE DESCRIPTION – INSTALLATION
Normally FAD-4 comes in a sealed stainless steel enclosure, suitable for wash down environment.
Entry of connecting cable is through sealed cable glands. Refer to Annex A for details of the enclosure and
main PCB 703.2. In addition an analogue output (PCB 760) and a tilt switch may be connected.
2.1 Mounting
The mounting location should be such that the unit is not subject to excessive vibrations or heat.
The top panel should be accessible.
2.2 Wiring
Remove the lid by undoing the four screws.
Insert cables via the cable glands. Strip the cables and connect the loadcells 1 to 4 to connectors ST6 to ST9
respectively. If the loadcell cables are 6 wire connect together the excitation and sense leads or cut off the sense
leads.
Connect the shields of the cables on SHLD terminal or directly on the chassis screws using eyelet terminals.
Power and communication cable is connected via cable gland s. See Annex A connector diagram for details.
Connect serial communication cable according to the drawing “FAD-4/703.2/88”.
When wiring is completed pull out any excessive cable and tighten the cable glands to ensure a firm grip
on the cables. Re-Install the lid and tighten the screws until the side edges are recessed 2mm from the lid edges.
FOR OPTIMUM EMC PERFORMANCE KEEP THE LENGTH OF THE SHIELD INSIDE THE
ENCLOSURE AS SHORT AS POSSIBLE.
2.3 Power
As the instrument is computer controlled it requires clean power for reliable operation.
Power supplied should come from a source that is isolated from other process equipment.
A mains adapter of 7,5 – 10 VAC / 500 mA is recommended for operation of both the RDT-52 and
FAD-4. Connect a power supply 7 - 10 VAC or 7.5 - 12 VDC (150mA min.) to ST1 or to Pin 8, 9 of
DB9 female connector (polarity independent).
2.4 Analogue output
Connect to ST2 of analogue output pcb760 according to drawing “FAD-4/760/040”.
2.5 Setpoint outputs
Connect isolated input / output to ST5 (if used) according to drawing “FAD-4/703.2/040”.
2.6 Tilt switch
Connect a dry contact to Pins 1 & 2 of ST3 directly or to Pins 2, 3 of D9 connector.
The tilt switch wires must be contained in the power and communications cable.
N.O or N.C contact and debounce timer are set in SETUP 1.
CAUTION : Do not run signal cables together with power cables.
Connect the shielding where indicated on the drawing only.
Never use a meg ger to check wiring.
Document
FAD - 4 DIGITAL LOADCELL JUNCTION BOX
Date
02.05.00 FAD4_2RM
Code
Rev.
2
Page
4 of 20
FLINTEC
3 FUNCTIONAL DESCRIPTION
All FAD-4 operations are performed via the serial interface, through the use of LESIP Master/Slave serial
interface protocol . The communication standards and timing are described in the LESIP manual. The file types
specific to FAD-4 will be described here. The FAD-4 is always a slave. In principle a number of FAD`s
may be connected in a network microprocessor controlled device.
The communication buffer size is 13 bytes max for Transmitter and Receiver (Half duplex).
Detailed description of the file types and sequences is given in the following pages .
LIST OF FILE TYPES (COMMANDS)
TYPE HEX DESCRIPTION TIME RESPONSE
? 3F UPLOAD WEIGHT & STATUS 50 ms STATUS + WEIGHT
A 41
a 61 DEADLOAD CAL(weights) 16 sec Poll slave by using command ‘?’
B 42 SPAN CAL (ELECTRONIC, mV/V input) 1.5 sec Poll slave by using command ‘?’
DEADLOAD CAL (ELECTRONIC mV/V)
1.5 sec Poll slave by using command ‘?’
b 62 SPAN CAL (weights) 16 sec Poll slave by using command ‘?’
C 43 DOWNLOAD mV/V for each corner 0.1 sec Poll slave by using command ‘?’
c 63 CALIBRATE CORNERS 16 sec Poll slave by using command ‘?’
d 64 UPLOAD AUDIT TRAIL CNT,CALLOCK 0.1sec 6 Digit counter, status Callock
f 66 UPLOAD CORNER FACTORS 0.1 sec FACTOR 1,2,3 ,4
G 47 GROSS 0.1sec NONE
H 48 RESERVED
i 69 UPLOAD INTERNAL RESOLUTION 0.1 sec INTERNAL DIVIDIONS
J 4A LOCK / UNLOCK CALIBRATION 0.1sec 6 Digit PIN or NAK
P 50 DOWNLOAD PAR 1/ PAR 2/ PAR 3 0.1 sec ACK or NAK
p 70 UPLOAD PAR 1/ PAR 2/ PAR 3 0.1 sec PAR 1/2/3
Q 51 DOWNLOAD SETPOINT 1 / SETPOINT 2 0.1 sec ACK or NAK
q 71 UPLOAD SETPOINT 1 / SETPOINT 2 0.1 sec SETPOINT 1/ SETPOINT 2
R 52 RESET SLAVE 16 sec NONE
S 53 DOWNLOAD SETUP : SETUP 1 / SETUP 2 0.1 sec ACK or NAK
s 73 UPLOAD SETUP1 0.1sec Setup1
T 54 TARE 0.1 sec NONE
W 57 WRITE TO EEPROM 16 sec NONE
Z 5A ZERO 3 sec NONE
Document
FAD - 4 DIGITAL LOADCELL JUNCTION BOX
Date
02.05.00 FAD4_2RM
Code
Rev.
2
Page
5 of 20
FLINTEC
FILE TYPE DESCRIPTION
Calibration and weight parameters are protected by calibration lock devices hardware and software.
If the CALIBRATION LOCK is activated, weight parameter/ calibration file types are not accessible.
The “CAL LOCK” is a hardware jumper inside the DJB required by Weights & Measures authorities
so that calibration can be sealed (jumper inserted).
The “PINLOCK” is a software Personal Identification Number, which ensures that no accidental
scale calibration is attempted. The “PIN LOCK” and the “CAL LOCK” are logically connected.
In addition to the “CAL LOCK” an A.T.CNT (Audit Trail Counter) is provided for use by
Weights and Measures Authorities.
The A.T.CNT (6 digits) is incremented when a weight parameter is changed, or a corner / scale
calibration is attempted, regardless if the changes are saved in EEPROM or not.
The position of the “CAL LOCK” jumper and the A. T. CNT number may be inspected with
Fn 48 (chapter 6).
The A.T.CNT may be viewed by the Weight & Measures to verify that no calibration constants have
been altered since the inspection/stamping date .
To avoid wait time in certain commands, (especially when units are connected in a network), the
DJB will not respond to the command issued but on subsequent polls by command “?”.
? UPLOAD STATUS
It is the main command used to poll the FAD(s), which reply with the current weight being
measured or with a message if bit0 of status byte is ‘1’. In the normal state the FAD-4 will respond
within 3-4 character time. (e.g. with 9600baud, the character time ≈ 1 msec, the master should
expect reception of STX from the FAD-4 within 5 msec after the ETX was transmitted from the
master).
Master transmission
STX ADD ? BCS2 BCS1 ETX
Slave response
STX ADD X STATUS BYTE WEIGHT BCS2 BCS1 ETX
where X= ‘?’ if there is new A/D conversion since the last weight value transmission.
X=’ ’ if there is no new A/D conversion since the last weight value transmission.
and WEIGHT: 5 digits + decimal point if any.(ASCII,MSD FIRST)
STATUS BYTE
b7 b6 b5 b4 b3 b2 b1 b0
Zero or
Parity
1 Sign of
weight
0=+ 1=-
The WEIGHT field will contain a message if b0 of the status byte is high.
A . DEAD LOAD CALIBRATION (ELECTRONIC mV/V)
Downloads the total mV/V output of the empty scale for dead load calibration.
Master transmission :
STX ADD A yyyyyy BCS2 BCS1 ETX
yyyyyy : 6 digits of mV/V multiplied by 10000 (ASCII decimal).
Poll the slave by using command ‘?’. Possible response messages: ‘WAIT..’ or ‘ERR 91’.
Slave returns to normal Weight output after the command is completed.
THE VALUE IS NOT SAVED IN EEPROM UNTIL A STORE COMMAND IS ISSUED.
No Motion
0=NO,
1=YES
Out of Range
0=NO
1=YES
Autozero
0=NO
1=YES
0=Gross
1=Net
0=Normal Weight
1=No Weight Display
Document
FAD - 4 DIGITAL LOADCELL JUNCTION BOX
Date
02.05.00 FAD4_2RM
Code
Rev.
2
Page
6 of 20
FLINTEC
EXAMPLE: For a 0,1234 mV/V loadcell deadload output the data downloaded must be 001234.
Master transmission :
STX A A 001234 0 0 ETX
Master transmission:
STX A ? = 3 ETX
Slave response:
STX A ? E WAIT.. 2 3 ETX
a. DEADLOAD CALIBRATION (WEIGHT)
When this command is received the FAD-4 will measure the weight of the empty scale by
averaging 32 conversions. This DEADLOAD average will be held in the ZERO CALIBRATION
memory.
Master transmission:
STX ADD a BCS2 BCS1 ETX
Poll the slave by using command ‘?’. Possible response messages: ‘WAIT..’ or ‘ERR 91’ .
Slave returns to normal weight output mode after the command is completed.
THE VALUE IS NOT SAVED IN EEPROM UNTIL A STORE COMMAND IS ISSUED.
B. SPAN CALIBRATION (ELECTRONIC, mV/V)
Used to download the capacity of each loadcell for SPAN factor computation .
The command must be preceded by command “C”.
Master transmission:
STX ADD B yyyyy BCS2 BCS1 ETX
yyyyy: 5 digits without decimal point (ASCII decimal)
Poll the slave with command ‘?’. Possible responses: “WAIT..” or “ERR 90” or “ERR 91”.
Slave returns to normal weight output mode after the command is completed.
THE VALUE IS NOT SAVED IN EEPROM UNTIL A STORE COMMAND IS ISSUED.
b. SPAN CALIBRATION (WEIGHTS)
Used to download the known WEIGHT already placed on the scale for Span factor computation.
Master transmission:
STX ADD b yyyyy BCS2 BCS1 ETX
yyyyy: 5 digits without decimal point (ASCII decimal)
Poll the slave with command ‘?’. Possible responses: “WAIT..” or “ERR 90” or “ERR 91”.
Slave returns to normal weight output mode after the command is completed.
THE VALUE IS NOT SAVED IN EEPROM UNTIL A STORE COMMAND IS ISSUED.
C. DOWNLOAD mV/V OF EACH CORNER
Used to download mV/V output at rated capacity of each loadcell. The loadcells must be of the
same rated capacity. The FAD-4 will expect the data for the number of loadcells stated in P1
command.
Master transmission:
STX ADD C 1 yyyyyy BCS2 BCS1 ETX
yyyyyy : 6 digits (ASCII decimal) of rated mV/V multiplied by 10000 for CORNER 1.
Poll the slave by using command ‘?’. Possible response messages: “ERR 91” or “CORN.2”
Master transmission:
STX ADD C 2 yyyyyy BCS2 BCS1 ETX
yyyyyy : 6 digits (ASCII decimal) of rated mV/V multiplied by 10000 for CORNER 2.
Document
FAD - 4 DIGITAL LOADCELL JUNCTION BOX
Date
02.05.00 FAD4_2RM
Code
Rev.
2
Page
7 of 20
FLINTEC
Poll the slave by using command ‘?’. Possible response messages: “ERR 91” or “CORN.3”
Master transmission:
STX ADD C 3 yyyyyy BCS2 BCS1 ETX
yyyyyy : 6 digits (ASCII decimal) of rated mV/V multiplied by 10000 for CORNER 3.
Poll the slave by using command ‘?’. Possible response messages: “ERR 91” or “CORN.4”
Master transmission:
STX ADD C 4 yyyyyy BCS2 BCS1 ETX
yyyyyy : 6 digits (ASCII decimal) of rated mV/V multiplied by 10000 for CORNER 4.
Poll the slave with command ‘?’.
Slave returns to normal Weight output after command is completed.
c. CALIBRATE CORNERS (WEIGHT)
It is used to compute correction factors for the corners by using weight equal to 10 - 30% of each
loadcell capacity. This command is in fact a procedure having a number of steps equal to the stated
number of loadcells. Empty the scale and send command:
Master transmission:
STX ADD c 0 BCS2 BCS1 ETX
Poll the slave by using command ‘?’.
Possible response messages: “WAIT..” or “ERR 91” or “CORN.1”.
Place the test weight on scale CORNER 1,wait to stabilise and send command:
Master transmission:
STX ADD c 1 BCS2 BCS1 ETX
Poll the slave by using command ‘?’.
Possible response messages: “WAIT..” then “CORN.2” if corner 1 was ok,
or “CORN.1” if something is wrong. If the same corner is returned repeat the procedure.
Place the same test weight on scale CORNER 2, wait to stabilise and send command:
Master transmission:
STX ADD c 2 BCS2 BCS1 ETX
Poll the slave by using command ‘?’.
Possible response messages: “WAIT..” then “CORN.3” if corner 1 was ok,
or “CORN.2” if something is wrong. If the same corner is returned repeat the procedure.
Place the same test weight on scale CORNER 3, wait to stabilise and send command:
Master transmission:
STX ADD c 3 BCS2 BCS1 ETX
Poll the slave by using command ‘?’.
Possible response messages: “WAIT..” then “CORN.4” if corner 1 was ok,
or “CORN.3” if something is wrong. If the same corner is returned repeat the procedure.
Place the same test weight on scale CORNER 4, wait to stabilise and send command:
Master transmission:
STX ADD c 4 BCS2 BCS1 ETX
Poll the slave by using command ‘?’.
Possible response messages: ’WAIT..’ then ‘CORN.4’ if something is wrong else the slave
returns to normal weight output mode.
If the same corner is returned repeat the procedure .
THE VALUES ARE NOT SAVED IN EEPROM UNTIL A STORE COMMAND IS ISSUED.
Document
FAD - 4 DIGITAL LOADCELL JUNCTION BOX
Date
02.05.00 FAD4_2RM
Code
Rev.
2
Page
8 of 20
Loading...