|
PD
3250 ANALOG INTERFACE MODULE
FEATURES
* 16 High
resolution (15 bit) 0-100mV or Thermocouple inputs
*
Linearisation for Thermocouple types:
R,S,B,J,T,E,K & N
* 1 High
resolution (15 bit) Pt-100 input
* Filtered
input signals
* Suppression
of 50 & 60 Hz noise
* High and
Low level limit switch on each channel
* Advanced
self test facility
* Overload
protection
* P-NET
Fieldbus communication
* Watchdog
Timer
* Rail
Mounting module (DIN / EN)
* EMC
Approved (89/336/EEC)
APPLICATION
The PD 3250 Analog Interface Module
(AIM), is one of a collection of distributed process control units, intended for
use within a P-NET Fieldbus system. It provides highly a versatile interface for
measurement transducers generating analog voltage signals (0 -100 mV), and for a
wide range of Thermocouple devices.
The PD 3250 provides internal conversion of voltage measurements into any
engineering unit representing the analog process being monitored and controlled.
In the case of thermocouple utilisation, ranging and linearisation are
automatically applied, depending on the particular thermocouple type defined.
Furthermore, an additional Pt-100 temperature input can provide an absolute
temperature offset to any of the thermocouple measurements. All fully processed
measurements are available for direct interrogation by central control or any
other master unit connected to the P-NET fieldbus.
The compact design and outstanding environmental features, makes the Analog
Interface Module an ideal process component within industrial, as well as other
environments.
SYSTEM DESCRIPTION
The PD 3250 module is an intelligent
measurement device, provided with 16 independent analog input channels for use
with a wide range of thermocouple transducers, and/or for 0-100mV signals. Also
included is a Pt-100 temperature reference input, and a communications interface
for the P-NET fieldbus.
The PD 3250 utilises 4 analog to digital converters, functioning with a fully
integrating principle. Each measurement is integrated over a 100mS period, which
reduces the influence of noise, and results in highly stable input signal
measurement readings. Input signals are galvanically isolated from the power
supply.
The unit offers comprehensive self testing features, which enables the reporting
of disconnection, overload and process failure. All inputs are protected against
overload. The selectable watchdog timer generates an internal error message
during a communications, or power failure.
All input signals are filtered and
suppressed against 50 and 60 Hz interference. An additional filter may be
applied to the input signal. The filter time constant is configurable for each
channel.
As a distributed module, the unit can be mounted close to the process. Data
communications between modules and controllers, are made using a single P-NET
cable, having a ring length of over 1Km. This reduces plant wiring costs to a
minimum.
The module may be plugged directly onto a mounting rail within a panel (EN 50
022 / DIN 46277), or in a box designed for the plant environment
SPECIFICATIONS (applicable within worst case EMI conditions)
Analog input (0-100mV):
Measurement error :
@ 0 C to +50 °C, max. ± 0.1 % of act. vol. ± 10 µV
@ -25 C to 70 °C, max. ± 0.3 % of act. vol. ± 10 µV
Resolution
:
5µV
Scale Drawing (in mm)
Repeatability
:
± 10µV 
Input impedance:
min. 5 M W
Analog input (Thermocouple):
Measurement error: As above, except
error due to repeatability depends on thermocouple device type. Refer to PD 3250
manual 502 082
Power Supply:
Voltage:
24V DC 15 %
Consumption:
max.
1.3 W
Ambient Temperature:
Operation:
-25 °C to +70 °C
Storage:
-40 °C to +85 °C
Temperature input (Pt-100):
Accuracy @ -100
°C
max. ± 0.19 °C
Accuracy @ 20
°C
max. ± 0.29 °C
Accuracy @ 200
°C
max. ± 0.51 °C
Input Measurement update
time:
Analog
inputs:
1 - 4 channels
enabled
0.6 s
1 - 16 channels
enabled
1.5 s
Temperature input:
1 - 4 channels
enabled
1.8 s
1 - 16 channels
enabled
4.5 s
PD 3250 is approved in compliance
with EMC Directive No. 89/336/EEC. Test limits are determined by the generic
standards EN 50081-1 for emission and EN 50082-2 for immunity. PD 3250 is
approved in compliance with the IEC 68-2-6 Test Fc standard for vibration
| 
