Datascan 7000 Manual
The Datascan Installation and User Guide is a brief introduction to
the Datascan 7000 series of Data Acquisition Modules. The guide provides all necessary
information to install the modules, configure the various DIP switches and connect the
input and output sensors.
For more detailed information including the in built
software commands and specification refer to the Datascan Technical Reference Manual
obtainable from your local Datascan Distributor. Detailed specifications for each module
can also be obtained from the respective data sheets.
General
The Datascan 7000 is a series of intelligent measurement
and data collection units developed for factory, industrial and scientific data
acquisition applications. Datascan 7000 provides new concepts and
standards in interfacing sensors to computers.
Due to its modular concept, a Datascan 7000 system can vary
from a minimum configuration,
consisting of a single Measurement Module, with suitable scanning units (see Figure 1.1),
up to
a 'full blown' 1000 channel system comprising many Measurement Modules and Scanner Modules
linked by their own proprietary RS485 local area network.
Datascan Module Range
Measurement Processors
Measurement Processors are modules that contain the A/D
Converter, microprocessor with
battery backup memory and power supply. They also provide the RS232 link capabilities to a
host computer or local monitor as well as the isolated RS485 network interface.
7010 A
measurement processor that has no on board channel inputs but does provide full local
channel expansion capability (up to 256 channels per module).
7220 A
measurement processor that provides directly 16 analog inputs. This module can be
connected to the RS485 Datascan network but does not have any local channel expansion
capability.
7221 A
measurement processor that provides directly 8 analog inputs including channel excitation.
This module can be connected to the RS485 Datascan network but does not have any local
channel expansion capability.
7250 A
measurement processor that provides directly 8 analog inputs and 8 analog outputs.
This module can be connected to the RS485 Datascan network but does not have any local
channel expansion capability.
7320 A
measurement processor that provides directly 16 analog inputs as well as full local
channel expansion capability ( up to 256 channels per module).
7321 A
measurement processor that provides directly 8 analog inputs, including channel excitation
and full local channel expansion capability ( up to 256 channels per module).
7327 A
measurement processor that provides directly 16 reed relay isolated analog inputs as well
as full local channel expansion capability ( up to 256 channels per module).
Analog Expansion Scanner Modules
Analog expansion modules provide additional local analog
input and output capabilities to the
7010, 7320, 7321 and 7327 Measurement Processors. Up to 256 channels can be connected
to the Measurement Processor. See Section 5 for further information on each scanner
module.
7020
Provides 16 analog input channels per scanner.
7021 Provides
8 analog input channels per scanner, with excitation for transducers.
7026 Provides
8 channels of solid state isolated analog inputs.
7027
Provides 16 channels of isolated (reed relay) analog inputs.
7050 Provides
8 analog input channels and 8 analog output channels.
Digital
Expansion Scanner Modules
Digital expansion modules provide digital input and output
capabilities to the 7010, 7320,
7321 and 7327 measurement Processors. Up to 256 channels can be connected to the
Measurement Processor. See Section 5 for further information on each scanner module.
7031 Provides
16 digital input channels.
7035 Provides
16 digital output channels.
7036 Provides
8 digital input and 8 digital output channel capability.
7041 Counter
Timer module provides pulse count and frequency measurement capability
up to 3.5Khz. 8 input channels up to 3.5Khz and 8 up to 10 Hz.
Gateway and
Peripheral Modules
7011
Provides a low cost method of connecting a PC or local terminal to a Datascan
Network when there is no local measurement processor.
7011-M The
7011-M is a Modbusä protocol converter for the Datascan System. The
module interfaces a Modbusä ASCII protocol master for configuration, reading and the
writing of channels on the Datascan System.
Typical Datascan Installation
Figure .1 Typical Datascan Installation
Figure 1.1 depicts a typical Datascan installation. The
host computer is located in a factory office
some distance from the main Datascan system. A 7011 Gateway module provides a local RS232
link to the host computer as well as linking to the rest of the Datascan Modules via the
RS485 network.
A 7320 Analog Measurement processor modules is sited
adjacent to the production line. This
7320 and attached scanner modules collect information from the line. Connected to the
RS485
network is a single 7321 located in the boiler room. It collects data from the boiler. In
the
equipment control room further Datascan modules acquire data and also provide output
control signals.
It can be seen from this example that by positioning the
Datascan modules close to the
sensors they are measuring and then connecting the modules via the RS485 network
keeps the wiring costs of the system to a minimum.
Measurement Processor
The heart of the Datascan System is the Measurement
Processor. Each processor
can be used autonomously or as part of a larger system via the Datascan network
( see Figure 1.1).
The measurement processor performs the measurement and
control of the Datascan
system. Measurement is carried out by a powerful Analog to Digital converter which
can be programmed to provide either 16 or 14 bits of resolution and is sensitive to 0.625m
V.
Further channel expansion, except 7200 processors, is by
means of a local expansion
bus providing a total of 256 channels connected directly to the local expansion bus.
The channels can be a mixture of analog and digital inputs; analog and digital outputs;
and pulse inputs.
Each measurement processor module has two communication
ports, an isolated RS232
port for communication with host computers or local display terminals, and an isolated
RS485 network port for connecting up to 32 measurement modules over a network
distributed up to 1.2 km. The isolated nature of these ports prevents ground loop
problems and protects the network and host computer in the event of high voltages
entering the measurement modules.
The CMOS design of the module limits the typical power
requirements to less
than 2 watts. Power is supplied as 24V AC or DC (7300 24V DC only) enabling
it to be easily installed into factory supplies.
Scanner Expansion Bus
Each 7300 series and 7010 module provide an expansion bus
for the connection
to Datascan scanner modules.
The scanner modules are simply daisy chained using the 26
way connector on
the modules. Up to 256 channels, both analog and digital, inputs and outputs
including those on the 7300 module can be connected to a single 7010 or 7300
Measurement Processor through the expansion bus. These can be connected
locally over a total distance of 10 metres.
Note:
The maximum number of channels connected to a 7010 or 7300
series module are reduced when the following scanner modules
are added: 7026, 7027, 7050, 7031, and 7036. Refer to section 3.1
for further information.
RS232 Isolated
Local Interface
The serial port is isolated to 500V DC and enables the user
to communicate with the
Measurement Processors using a standard computer or VDU( (TV 925/VT100 etc.,).
The baud rate is switch selectable between 4800, 9600, 19200, or 38400.
RS485
Isolated Network Interface
One of the unique features of the Datascan 7000 series of
Measurement Processors
is its distributed networking capability. Each processor module can operate autonomously
with its own local input and output modules, or alternatively can be connected to a
network
cluster of up to 32 measurement processors.
The token passing network can operate over a distance of
1.2 Km (4000ft) using a standard
screened twisted pair cable and can support a total of 32 Measurement Processors, with
up to 1000 channels of all types being distributed along the network.
The network is self configuring. This means that units can
be added or removed from the
network with minimal disturbance to the data transmission.
The network is fully isolated to 500 Volts, protecting
other modules on the network in the
unlikely event of mains voltage being applied to the network or to a specific module on
the network.
Power Supply
The power supply of the Datascan Measurement processor
provides the power for both
the local module and that of the modules attached to it via the scanner expansion bus.
The unit will accept an input supply of 24V AC or DC. ( 7300 24V DC only)
System Specification
ADC Resolution 16 bit or
14 Bit (7027 16 bit only)
Software Programmable
ADC Measurement Speed
(Individual Channel Speed Selection) 40 conversions / sec
at 16 bit
400 conversions / sec at 14 Bit
Measurement speed 1 Hz
typical
RS232 Host Communication
Baud rates 4800, 9600, 19200 38400 (Switch selectable)
RS232 Cable length 10m maximum
RS232 Isolation 500V DC
Local Expansion Bus
Total no. of channels 256 max.
Expansion cable 26 way ribbon cable (supplied)
Maximum cable length 10 metres
RS485 Network
Electrical specification RS485
Transmission 93.75Kbaud
RS485 Isolation 500 V DC
Data Rate 1000 results/second
Total Channels per network 1000
Maximum Length 1.2Km (4000 ft)
Maximum number of nodes 32
Recommended Cable Types Belden 9207 (up to 1.2km) Belden
8761 (up to 300m)
Environmental
Operating Temperature -10 to 60 ° C
Storage Temperature -20 to 80 ° C
Relative Humidity 0 - 90% RH non condensing
Power
Requirements & Dimensions
Note:
When using 7050 Modules. If the module is being used as a
set of 4 to 20mA sources, an external, isolated 24V DC supply MUST be connected
(e.g. 7981), to the auxiliary 24V input connections on each 7050 module.
