Sensoray 2518 - Manual (Page 6)

Sensoray Model 2518/2519 Ethernet Smart A/D™ 3 Introduction
2.2 Product Features
q Remote operation on any 10BASE-T Ethernet
network.
q Up to 4096 sensor channels per network, using up to
256 distributed Ethernet Smart A/D™ units.
q High-performance dedicated network processor with
optimized TCP/IP stack delivers up to 1400
transactions per second.
q On-board DC-DC converter requires only a single
12V to 24V AC/DC input power source.
q
Robust, pluggable screw terminal blocks support
direct sensor connections.
q Network watchdog timer monitors Ethernet activity.
q
Embedded processors off-load computationally
intensive data acquisition functions from the client.
q Each sensor channel may be dynamically configured
to accept any supported sensor type.
q Fully differential sense inputs help to eliminate
ground loops.
q All sense inputs are protected from high differential
and common mode voltages.
q Pulsed excitation provided for thermistors, resistors,
RTDs and strain gages. Pulsed excitation minimizes
sensor self-heating and helps to reduce system power
consumption.
q
Sensor excitation signals are electrically separate
from the sense inputs so that high accuracy
three-wire or four-wire circuits may be implemented.
q
Automatic reference junction compensation provided
for thermocouples. Integral compensation sensors
occupy dedicated measurement channels so that all
process sensor channels remain available for
application use.
q Programmable alarm thresholds for each channel. A
single Alarm flag enables the rapid detection of limit
violations without burdening clients with sensor data
evaluation.
q
High quality internal reference standards for
excellent long-term stability and accuracy.
2.3 Block Diagram
Figure 2: Model 2518/2519 Block Diagram
12 to 24VDC
Excitation
Generator
Digitizer
Excitation
Mux
Sense
Mux
Reference
Standards
Ethernet
µComputer
Ethernet
Interface
Model 518 Smart A/D™ (2518/2519)
P
C
/1
0
4
B
u
s
Network
Processor
Model 518 Smart A/D™ (2519 only)
Screw
Terminals
Model 2509 Ethernet Base Unit
Temp.
Sensor
Process
Sensors
Power
Supplies