Chapter 1 Preface 1
EC20 Series PLC User Manual
Chapter 1 Preface
Thank you for using EC20 series Programmable Logic Controller (PLC) made by Emerson Network Power Co., Ltd.
This book contains text, diagrams and explanations that will guide the reader in the correct installation and operation
of the EC20 series PLC and should be read and understood before attempting to install or use the product.
The book describes the hardware, features and applications of the EC20 series PLC, also includes the options
introduction, troubleshooting guide and instruction quick reference. For the information about how to setup an EC20
programming system and the customer programming application, please refer to ControlStar Programming Software
User Manual or EC20 series PLC Programming Manual printed by Emerson Network Power Co., Ltd. For ordering
the above user manuals, contact your Emerson distributor or sales office.
This manual is designed for the engineer who is studying, programming, installing, or servicing the EC20 series PLC.
Definitions of specific terms
PLC: Programmable Logic Controller
Main module: Refer to basic module or CPU module; it is the basic unit of the PLC. It includes master CPU, I/O ports
and power supply.
Expansion module: Generally refer to the modules except for the main module.
I/O expansion module: The expansion module for the digital signal input/output.
Special function module: Other function expansion modules except for the I/O expansion module, such as analog
signal input/output module, and busbar module.
Points: The sum of channel number of the input/output digital signal.
Digital signal: Refer to the input/output signals that only have two states: “ON” and “OFF”.
Analog signal: Continuously changed electric signal, such as 4~20mA output signal of pressure transmitter.
Unipolar signal: Generally refer to the continuously changed signal with positive polarity.
Bipolar signal: Generally refer to the continuously changed signal, which may be positive polarity or negative
polarity.
High-speed pulse: Refer to the square-wave signal with higher frequency.
Counter: Refer to the counter whose counting value increases or decreases by per pulse input according to the
increasing/decreasing control signal.
Two-phase counter: refer to the counter that has two-pulse input ports, one is for counting up, and the other is for
counting down.
AB-phase counter: refer to the counter that has two input ports of quadrature phase pulse, and counts up or down
according to the frequencies and phase differences of the two signals.
To Next Page
Loading...
Need help?
General
