IVC-EH-4PT Resistance-type
Temperature Input Module
User Manual
Thanks for choosing the programmable logic controllers (PLCs) developed
and produced by INVT Auto-Control Technology (Shenzhen) Co., Ltd. Before
using the IVC-EH-4PT series PLC products, read this manual carefully to
understand the product features, so that you can install and use the products
properly and make full use of its abundant functions.
Note:
Before using the product, read the operation instructions and precautions
carefully to prevent accidents. Only trained personnel can install and operate
the product, and when installing and operating the product, the operators
must strictly follow the related industrial safety specifications and the
precautions and special safety guide provided in this manual to perform
operations properly.
1 Interface description
1.1 Interface introduction
Cover plates are provided for the extension cable interfaces and user
terminals of the IVC-EH-4PT module, as shown in Figure 1-1. You can see
the extension cable interfaces and user terminals after opening the cover
plates, as shown in Figure 1-2.
Figure 1-1 Module appearance
diagram
Figure 1-2 Module interface
diagram
The IVC-EH-4PT module is connected to the main module through a patch
board, and the extension modules are connected in cascade mode to
implement hard connection. For the specific connection method, see the
connection diagram in Figure 1-3.
Table 1-1 describes the definition of
IVC-EH-4PT
user terminals.
Table 1-1 Definition of IVC-EH-4PT user terminals
SN Label
Description
SN Label
Description
1 24V+
Positive pole of the 24 V
analog power supply
11
R2–
Negative input terminal of
thermistor signals of
channel 2
2 24V–
Negative pole of the 24 V
analog power supply
12
I2–
Auxiliary negative input
terminal of thermistor
signals of channel 2
3
.
Empty pin
13
R3+
Positive input terminal of
thermistor signals of
channel 3
4 PG
Ground terminal
14
I3+
Auxiliary positive input
terminal of thermistor
signals of channel 3
5 R1+
Positive input terminal of
thermistor signals of
channel 1
15
R3–
Negative input terminal of
thermistor signals of
channel 3
6 I1+
Auxiliary positive input
terminal of thermistor
signals of channel 1
16
I3–
Auxiliary negative input
terminal of thermistor
signals of channel 3
SN Label
Description
SN Label
Description
7 R1–
Negative input terminal of
thermistor signals of
channel 1
17
R4+
Positive input terminal of
thermistor signals of
channel 4
8 I1–
Auxiliary negative input
terminal of thermistor
signals of channel 1
18
I4+
Auxiliary positive input
terminal of thermistor
signals of channel 4
9 R2+
Positive input terminal of
thermistor signals of
channel 2
19
R4-
Negative input terminal of
thermistor signals of
channel 4
10 I2+
Auxiliary positive input
terminal of thermistor
signals of channel 2
20
I4-
Auxiliary negative input
terminal of thermistor
signals of channel 4
1.2 System connection
IVC-EH-4PT is applied to IVC3 series PLC systems. It can be connected to
an IVC3 series system through hard connection, that is, inserting it into the
extension interface of any extension module of the main module or system,
as shown in Figure 1-3.
After the IVC-EH-4PT module is connected to the system, its extension
interface can also be used to connect another extension module of the IVC3
series, such as the I/O extension module, VC-EH-4DA, IVC-EH-4TC, or
another IVC-EH-4PT.
The main module of an IVC3 series PLC can be extended with multiple I/O
extension modules and special function modules. The number of extension
modules depends on the power that the module can supply. For details, see
section 4.7 "Power supply specifications" in the
IVC3 Series PLC User
Manual
.
Figure 1-3 Diagram of the connection between IVC-EH-4PT analog
input modules and the main module
1.3 Wiring description
Figure 1-4 shows the user terminal wiring requirements. Pay attention to the
following seven aspects:
1. The labels
①
to
⑤
in Figure 1-4 indicate the connection that you need
to pay special attention to.
2. It is recommended that you connect the thermistor signals by using a
shielded twisted-pair cable, and keep the cable away from power cables
or other cables that may cause electrical interference. The connection of
a thermistor is described as follows:
(1)
For thermistor sensors of the Pt100, Cu100, and Cu50 types, you
can use the 2-wire, 3-wire, and 4-wire connection methods.
Among them, the precision of the 4-wire connection method is the
highest, that of the 3-wire connection method is the second
highest, and that of the 2-wire connection method is the lowest. If
the length of the wire is longer than 10 m, it is recommended that
you use the 4-wire connection method to eliminate the resistance
error caused by the wire.
(2)
To reduce measurement errors and prevent noise interference, it
is recommended that you use connection cables that are shorter
than 100 m. Measurement errors are caused by the impedance of
connection cables and may be different on different channels of
the same module. Therefore, you need to adjust the characteristic
of each channel. For details, see section 3 "Characteristic setting".
3. If too much electrical interference is caused, connect the shielding
ground to the ground terminal PG of the module.