West Control Solutions Pro-EC44 - Manual (Page 33)

Pro-EC44 2-Loop Graphical Profile Controller & Recorder
Pro-EC44 Product Manual - 59540-1 October 2013 Page 26
Plug-in Module Slot A - Ethernet Communications Module
If fitted with the Ethernet communication module, the communications protocol available is
Modbus TCP. Isolated from all inputs/outputs. If necessary, cut out the removable panel to
access the RJ45 connector through the top of the case. No rear connections are required.
Plug-in Module Slot A - RS485 Serial Communications Module
If fitted with the RS485 serial communication module, the protocol used is Modbus RTU.
Isolated from all inputs/outputs. Carefully observe the polarity of the A (Rx/Tx +ve) and B
(Rx/Tx -ve) connections.
Figure 39. Plug-in Module Slot A
– RS485 Serial Communications Module
CAUTION: External computing devices connected to the communications
port should comply with the standard, UL 60950.
Plug-in Module Slot A
– Single Digital Input Module
If a digital input module is fitted, it provides a fully isolated input that is held high via a pull-up
resistor. The input can be connected to either to voltage free contacts (e.g. from a switch), or
a TTL compatible signal.
Logic High = Open contacts (>5
000Ω) or 2 to 24VDC signal.
Logic Low = Closed contacts (<50Ω) or -0.6 to +0.8VDC signal.. Connect as shown.
Figure 40. Plug-in Module Slot A
– Digital Input A Module