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Installation
2.12 Discrete Input Connections
The
PM295
provides eight optically isolated dry-contact sensing (voltage-free)
discrete inputs.
Figure 2-19
shows wiring for discrete inputs.
K1
K2
K3
K4
K5
K6
K7
K8
COM
6
8
12
10
14
16
18
20
11
+5 V
0 V
1 kOhm
PM295
Figure 2-19 Discrete Input Connections
The dry contacts connected to discrete inputs must be floating relative to the ground
with a minimum rating of 5 VDC, 5 mA. It is also recommended to perform
connections using a shielded, twisted pair cable that is isolated from noise sources.
2.13 Communications
Connector Pinout
The communications port is optically isolated and supports both EIA RS-232
and
RS-422/485 standard interfaces (user-selectable). The serial interface connector is
standard D-type 9 pin female plug-in, located at the top center of the back of the
instrument.
Tables 2-1
and
2-2
list the pinout of the connector.
NOTE
The functions of pins 4 and 5 can be programmed via keypad upon the needs of the user.
Refer to Section 5.3 on how to select the appropriate pin function.
Table 2-1 RS-232 pinout
Pin
Name
Function
1
0V
Common
2
TXD
Transmit Data
3
RXD
Receive Data
4
DTR/RTS
Data Terminal Ready/Request to Send
5
DSR/CTS
Data Set Ready/Clear to Send