Contrec 505 BC01 User manual

Model 505 Flow Computer
Operation Manual
Application BC01
Dual Stage Batch Controller
for
Volumetric Frequency Flowmeters
17 June 2017

Model 505 Flow Computer - Operation Manual
© Contrec Ltd 2017
The instructions given herein cover the general description, installation, operation and maintenance of the subject
equipment. Contrec Ltd reserves the right, without prior notice, to make engineering refinements that may not be
reflected in this manual.
Should any questions arise which cannot be answered specifically by this manual, they should be directed to
Contrec Ltd for further detailed information and technical assistance.
Contrec Ltd will not accept any liability for either direct or consequential damages resulting from the use or
misapplication of the contents of this manual.
Part of the software embedded in this product is eCos - Embedded Configurable Operating System, a trademark of
Red Hat. Portions created by Red Hat are Copyright © 1998, 1999, 2000 Red Hat, Inc.
(http://www.redhat.com). All rights reserved
The software in this product was in part provided by Red Hat and any express or implied warranties, including, but
not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no
event shall the author be liable for any direct, indirect, incidental, special, exemplary, or consequential damages
(including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business
interruption) however caused and on any theory of liability, whether in contract, strict liability, or tort (including
negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such
damage. Contrec Ltd
Riverside, Canal Road, Sowerby Bridge,
West Yorkshire HX6 2AY UNITED KINGDOM
Tel: [phone] Fax: [phone]
Email: [email protected]
Website: www.contrec.co.uk
Contrec Systems Pty Ltd
5 Norfolk Avenue Ringwood, Melbourne 3134 AUSTRALIA
Tel: [phone]
Email: [email protected]
Contrec - USA, LLC
916 Belcher Drive Pelham AL 35124 USA
Tel: [phone] Fax: [phone]
Email: [email protected]
Publication No: 505-BC01-OM - 17 June 2017

505 BC01 - 17 June 2017 iii
Safety Notice
The information in this safety notice is for the prevention of injury to personnel and
damage to the instrument.
The manufacturer assumes no liability for injury or damage caused by misuse of the
instrument or for modifications made to the instrument.
Qualified Personnel
The instrument must be installed, operated and serviced by persons who have been properly
trained and authorised. Personnel must read and understand this manual prior to installation and
operation of the instrument.
Static Hazard
The 500 series flow computer uses high speed CMOS circuitry which is sensitive to static
damage. The user should observe accepted safety practices for handling electronic devices,
especiallyduringservicing.Oncetheunitisinstalled,groundedandinterconnected,thechances
of static damage are greatly reduced.
Voltage Hazard
Before connecting power to the instrument, ensure that the supply voltage for the AC or DC
input is suitable. The AC voltage rating is as stated on the instrument rating plate. Personnel
should take all due care to avoid electric shock. For safe operation it is essential to connect a
mains safety earth to the A.C. power inlet. Do not operate at altitudes above 2000m.
Welding Hazard
Do not perform electric welding in close proximity to the instrument or its interconnecting
cables. If welding in these areas must be performed, disconnect all cables from the instrument.
Failure to do so may result in damage to the unit.
Moisture Hazard
To avoid electrical faults and corrosion of the instrument, do not allow moisture to remain in
contact with the instrument.
Disconnection Device
When powered from a mains supply this unit requires the provision of a suitable mains isolation
device to be accessible near to the installed instrument.
505 BC01 - 17 June 2017

iv 505 BC01 - 17 June 2017

v
1 Introduction
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Displayed Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Main Menu Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Retransmission & Control Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Relay Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Software Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2 Specifications
Specification Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3 Installation
Panel Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Electrical Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Rear Panel Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Terminal Designations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Frequency Input Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Logic Input Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4-20mA Output Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Digital Output Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Control Relays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
RC Network for Interference Suppression . . . . . . . . . . . . . . . . . . . . . . 12
Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
RS-232 Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
RS-485 Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Earthing and Shielding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4 Operation
Front Panel Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Default Variable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Status LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Front Panel Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Main Menu Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Setting the Batch Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Data Logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Model Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Batch Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Starting a Batch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Stopping a Batch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Resetting a Batch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Contents
505 BC01 - 17 June 2017

vi 505 BC01 - 17 June 2017
Logic Input Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Batch Flow Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Batch Control Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5 Instrument Calibration
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Calibration View Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Calibration Set Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Changing the Instrument Settings . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Calibration Menu Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Instrument Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Units of Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Time Settings and Data Logging . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
General Setup Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Test Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
System Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Warning Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
6 Communications
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Hardware Interconnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Modbus RTU Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
List of Data Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Printer Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Types of Printouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Printer Data Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Appendix A Model Numbers
Product Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Custom Version Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Application Information Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Appendix B Units of Measurement
Available Units of Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

vii505 BC01 - 17 June 2017
List of Figures
1 Typical Application Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 500 Series Instrument Panel Mounting . . . . . . . . . . . . . . . . . . . . . . . 7
3 Rear Panel Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4 Logic Input Connection Diagram . . . . . . . . . . . . . . . . . . . . . . . . . 10
5 Signal Input Connection Diagram . . . . . . . . . . . . . . . . . . . . . . . . . 10
6 Output 4-20mA Connection Diagram . . . . . . . . . . . . . . . . . . . . . . . 11
7 Output Pulse Connection Diagram . . . . . . . . . . . . . . . . . . . . . . . . 11
8 Relay Connection Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
9 RS-485 Interface Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
10 Batch Operation with Manual or Automatic Reset . . . . . . . . . . . . . . . . 22
11 Batch Operation with Automatic Restart . . . . . . . . . . . . . . . . . . . . . 22
12 Calibration Menu Tree Sheet 1 . . . . . . . . . . . . . . . . . . . . . . . . . . 26
13 Calibration Menu Tree Sheet 2 . . . . . . . . . . . . . . . . . . . . . . . . . . 27
14 RS-232 Cable Connections to a Computer . . . . . . . . . . . . . . . . . . . . 46
15 RS-485 Connections
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

viii 505 BC01 - 17 June 2017

1
Chapter 1
Introduction
Features •Tailored for volumetric frequency flow input
•Single or Dual stage control
•Quick access to common batch quantities
•No-flow, leakage and overflow error detection
•Remote RUN/STOP/RESET
•Allows for non-linear correction
•Storage of 100 transactions with time and date stamp
•Selection of second language and user tags
•Pulse width and scaling of pulse output
•4-20mA retransmission
•Selectable protocols on serial ports including Modbus RTU and Printer
output
•Front panel adjustment of 8-24V DC output voltage
•Backlit display with LCD backup
Overview
The 505 BC01 application is a dual stage batch controller for reliable
measurement of preset quantities using a volumetric frequency input. Used
as a single or dual stage controller it is suitable for fast batch applications.
It provides the operator with clear local readout and can be controlled via
communications in more automated systems. There is quick access to
commonly used preset values directly from the front panel if access has
been authorized. Automatic overrun compensation caters for system delays
such as valve closure for precise volumes.
The instrument is compatible with a wide range of flowmeter frequency
outputs, including millivolt signals, reed switches, Namur proximity
switches and pulse trains via its smart front-panel program selection.
505 BC01 - 17 June 2017

Introduction
2 505 BC01 - 17 June 2017
Calculations
The total and flowrate are derived from accurately measured frequency and
the number of received pulses.
volume = pulses / k-factor
volume flow = frequency / k-factor
Automatic overrun compensation calculates the new valve closure point to
ensure correct delivery by averaging the overrun amount from the last three
complete batches.
Theoverruncompensationvalue is valid for a new preset value provided the
stored overrun is less than 20% of the new preset.
Displayed Information
The front panel display shows the current values of the input variables and
the results of the calculations.
The instrument can be supplied with a real-time clock for storage of up to
100 transactions with time and date stamps.
Main Menu Variables
Refer to Available Units of Measurement on page 62 for the list of
available units.
Communications
There are two communication ports available as follows:
•RS-232 port
•RS-485 port
The ports are available for remote data reading, printouts and for initial
application loading of the instrument.
Main Menu
Variables Default Units Variable Type
Volume L Total
Volume Flowrate L/min Rate

Introduction
505 BC01 - 17 June 2017 3
Retransmission & Control Outputs
The instrument can retransmit any main menu variable. The digital outputs
can retransmit totals as pulses or operate as logic levels for control or error
outputs. If the instrument has the advanced option, it outputs rates as a 4-
20mA signal.
Relay Outputs
The relay outputs 1 and 2 are used to control the flow of product for each
delivery. These contacts are normally open and can be used to drive external
relays, valves, pump circuits etc.
Software Configuration
The instrument can be further tailored to suit specific application needs
including units of measurement, custom tags, second language or access
levels. A distributor can configure these requirements before delivery.
Instrument parameters including units of measurement can be programmed
in the field, according to the user access levels assigned to parameters by the
distributor.
All set-up parameters, totals and logged data are stored in non-volatile
memory with at least 30 years retention.
Figure 1 Typical Application Diagram
Main Flow
Control Valve
Frequency
Input
Bleed Flow
Relay 1 Relay 2
Control Valve
Example of
dual stage
batching
Volumetric
Flowmeter

Introduction
4 505 BC01 - 17 June 2017
Approvals This instrument conforms to the EMC-Directive of the Council of
European Communities 2014/30/EU, the LVD safety directive 2014/35/EU
and the following standards:
•EN61326:2013 Electrical equipment for measurement, control and
laboratory use – EMC requirements: Industrial Environment.
•EN61010:2010 Safety requirements for electrical equipment for
measurement, control, and laboratory use.
In order to comply with these standards, the wiring instructions in Chapter
3 - Installation must be followed.
FCC Declaration
This equipment has been tested and found to comply with the limits for a
Class A digital device, pursuant to Part 15 of the FCC Rules. These limits
are designed to provide reasonable protection against harmful interference
when the equipment is operated in a commercial environment. This
equipment generates, uses, and can radiate radio frequency energy and, if
not installed and used in accordance with the instruction manual, might
cause harmful interference to radio communications. Operation of this
equipment in a residential area is likely to cause harmful interference, in
which case the user will be required to correct the interference at his own
expense.
Properlyshieldedandgroundedcablesandconnectorsmust be used in order
to meet FCC emission limits. Contrec Ltd is not responsible for any radio or
television interference caused by using other than recommended cables and
connectors or by unauthorized changes or modifications to this equipment.
Unauthorized changes or modifications could void the user's authority to
operate the equipment.
This device complies with Part 15 of the FCC Rules. Operation is subject to
the following two conditions: (1) this device might not cause harmful
interference, and (2) this device must accept any interference received,
including interference that might cause undesired operation.

5
Chapter 2
Specifications
Specification Table
Operating Environment
Temperature 0°C to +60°C (conformal coating)
+5°C to +40°C (no coating)
Humidity 0 to 95% non condensing (conformal
coating)
5% to 85% non condensing (no coating)
Power Supply 95-135 V AC or 190-260 V AC
or 12-28 V DC
Consumption 6W (typical)
Protection Sealed to IP65 (Nema 4X) when panel
mounted
Dimensions
(panel option) 147mm (5.8") width
74mm (2.9") height
167mm (6.6") depth
Display
Type Backlit LCD with 7-digit numeric display
and 11-character alphanumeric display
Digits 15.5mm (0.6") high
Characters 6mm (0.24") high
LCD Backup Last data visible for 15min after power
down
Update Rate 0.3 second
Non-volatile Memory
Retention > 30 years
Data Stored Setup, Totals and Logs
Approvals
Interference compliance
Enclosure IECEx, ATEX and CSA approved
enclosures available for hazardous areas
Real Time Clock (Optional)
Battery Type 3 volts Lithium button cell (CR2032)
Battery Life 5 years (typical)
Frequency Input (General)
Range 0 to 10kHz
Overvoltage 30V maximum
Update Time 0.3 sec
Cutoff frequency Programmable
Configuration Pulse, coil or NPS input
Non-linearity Up to 10 correction points
Pulse
Signal Type CMOS, TTL, open collector, reed switch
Threshold 1.3 volts
Coil
Signal Type Turbine and sine wave
Sensitivity 15mV p-p minimum
NPS
Signal Type NPS sensor to Namur standard
Remote Logic Inputs
Signal Type Voltage free contact, open collector
Relay Output
No. of Outputs 2 relays
Voltage 250 volts AC, 30 volts DC maximum
Current 3A maximum
Communication Ports
Ports RS-232 port
RS-485 port
Baud Rate 2400 to 19200 baud
Parity Odd, even or none
Stop Bits 1 or 2
Data Bits 8
Protocols Modbus RTU, Printer*
505 BC01 - 17 June 2017

Specifications
6 505 BC01 - 17 June 2017
Important: Specifications are subject to change without notice.
Printer protocol is available only if RTC option is installed.
Transducer Supply
Voltage 8 to 24 volts DC, programmable
Current 70mA @ 24V, 120mA @ 12V maximum
Protection Power limited output
Pulse/Digital Output
Signal Type Open collector, non-isolated
Switching 200mA, 30 volts DC maximum
Saturation 0.8 volts maximum
Pulse Width Programmable: 10, 20, 50, 100, 200 or
500ms
4-20mA Output (Optional)
Supply 24 volts DC internal, non-isolated
Resolution 0.05% full scale
Accuracy 0.05% full scale (20C)
0.1% (full temperature range, typical)

7
Chapter 3
Installation
Panel Mounting
The instrument should be located in an area with a clean, dry atmosphere
that is also relatively free of shock and vibration.
The standard mounting procedure is panel mounting in a cutout that is
139mm wide by 67mm high. Two side clips secure the unit into the panel.
Figure 2 shows the panel mounting requirements for the 500 Series
Instrument.
Figure 2 500 Series Instrument Panel Mounting
145mm
Side View
22mm
70mm
67mm
139mm
25mm
66mm
Min. 189mm
Panel Cut-out
Front
Panel
74mm
Mounting Clip
138mm
147mm
Rear Connectors Top View RS232
Port
505 BC01 - 17 June 2017

Installation
8 505 BC01 - 17 June 2017
Electrical Connection
Rear Panel Connections
Figure 3 shows the connections on the rear panel of the instrument.
Figure 3 Rear Panel Connections
Terminal Designations
RS232 Port
CAUTION
MAINS
E N A
AC MAINS
123 456789101112131415161718 192021
RS485 RS232 Io SG Li Dout Ii SG Fi Vo GViSH RELAYS
+-GTxRx C + - + 1+ 2+ + - + + - + E R1 RC R2
TerminalLabel Designation Comment
1RS485 + RS485 (+)
2 - RS485 (-)
3 G Comms ground
4RS232 Tx RS232 data out Same RS232 port as
DB9 connector
5 Rx RS232 data in
6 C CTS (Clear to send)
7 Io + 4-20mA output Advanced option
8 SG - Signal Ground 0V
9 Li + Logic input Remote run
10 D OUT 1+ Open collector o/p 1 Digital outputs
11 2+ Open collector o/p 2
12 Ii + Signal input Remote stop/reset
13 SG - Signal Ground 0V
14 Fi + Frequency input Volumetric flow
15 Vo + 8-24 volts DC output 70mA power limited
16 G - DC Ground
17 Vi + DC power input DC power in 12-28V
18 SH E Shield terminal
19 RELAYS R1 Relay 1 Single stage
20 RC Relay Common
21 R2 Relay 2 Dual stage
EAC
MAINS
E Mains ground ACpowerin95-135V
or 190-260V
N N Mains neutral
A A Mains active
RS232 port 9-pin serial port

Installation
505 BC01 - 17 June 2017 9
Inputs
Frequency Input Connection
Connect pulse or frequency input signals from devices such as: TTL,
CMOS, open collector, reed relay switch, coil and Namur proximity switch,
as shown below. For better signal integrity, it is recommended to use
shielded cable. Refer to Terminal Designations on page 8 for specific
terminal numbers for this application.
Squarewave, CMOS or TTL
Open Collector
Reed Relay Switch
Coils - with 15 millivolts peak to peak AC minimum
Namur Proximity Switch
18 Shield
Signal Ground
13
Frequency
Input
(Fi)
14
Signal Ground
18 Shield
13
Frequency
Input
(Fi)
14
Signal Ground
18 Shield
13
Frequency
Input
(Fi)
14
NPN PNP
+V
Signal Ground
18 Shield
13
Frequency
Input
(Fi)
14
~
18
Signal Ground
Shield
13
Frequency
Input
(Fi)
14
15 Vo +8V DC
18 Shield
NPS
Frequency
Input
(Fi)
14

Installation
10 505 BC01 - 17 June 2017
Logic Input Connection
These input(s) are designed to be connected to open collector signals or a
voltage free contact switch. A minimum activation time of 300ms is
required to guarantee reading of an input.
Remote Run Input
A remote push-button key can be connected to the Logic Input (Li, terminal
9) as shown below.
Figure 4 Logic Input Connection Diagram
Remote Stop/Reset Input
A remote push-button key can be connected to the multipurpose Signal
Input (Ii, terminal 12) as shown below. A momentary press of the remote
key is recognised as a Stop signal, while a press and hold for 2 seconds is
recognised as a Reset.
Figure 5 Signal Input Connection Diagram
Outputs
The basic instrument has two digital outputs. The advanced option also
provides a 4-20mA output port.
4-20mA Output Connection
Figure 6 shows the connections for a 4-20mA output.
Maximum Load Resistance = 900 ohms
Signal Ground
8
Logic Input
(Li)
9
Signal Ground
8
Signal Input
(Ii)
12
15 Vo +8...24V DC
1K External
Pull Up

Installation
505 BC01 - 17 June 2017 11
Figure 6 Output 4-20mA Connection Diagram
Digital Output Connection
The digital outputs can be programmed in calibration to function as either a
flow error signal, end of batch signal, pump control output or a pulse output
for retransmission of totals.
Figure 7 shows a connection example for a pulse output. Output channel 1
uses terminals 10 (+) and 8 (-). Output channel 2 uses terminals 11 (+) and
8 (-).
Figure 7 Output Pulse Connection Diagram
Control Relays
The standard instrument has two relays, which are used for the dual stage
batch control. The relays can drive external devices such as valves, pump
circuits or external relays.
18
+
-
Load
Shield
505
4-20mA
Output
(Io)
7
8
Internal supply
+
-
External Load
Resistor 10K
Vo +8...24V DC 15
Logic Input
Open
Collector
Output
Pulse Output
(DOUT)
Shield
18
500

Installation
12 505 BC01 - 17 June 2017
The output characteristics of the relays are:
Note: Solid state relays use AC voltage only.
Figure 8 Relay Connection Diagram
RC Network for Interference Suppression
When driving highly inductive loads with the relay outputs, it is
recommended to use RC suppression networks (often called “Snubbers”)
for the following reasons:
•To limit the amount of electrical noise caused by arcing across the
contacts, which may, in extreme cases, cause the microprocessor to act
erratically.
•To protect the relay contacts against premature wear through pitting.
RC suppression networks consist of a capacitor and series resistor and are
commonly available in the electrical industry. The values of R and C are
dependent entirely on the load. However, if the user is unsure of the type of
snubber to use, values of 0.25F and 100will usually suffice. Note that
only mains-approved RC suppression networks should be used.
The basic principle of the operation is that the capacitor prevents a series of
sparks arcing across the contact as the contact breaks. The series resistor
limits the current through the contact when the contact first makes.
Communications
The communication protocols are described in Communications on
page 45.
RS-232 Port
The standard RS-232 port uses terminals 4, 5 and 6 on the rear panel.
Maximum Voltage 30 volts DC or 250 volts AC
Maximum Current 3A
Supply
Control Device
Relay 1
Relay 2
R2
R1
RC Relay Common
MOV
MOV
500
Control Device