S7-200 digital I/O module interface module, analog I/O modules and communication modules. These modules are introduced below.
(A) the digital I/O module
Digital I/O module is native integration to solve digital input/output points can not meet the need to use extension modules. S7-200PLC currently offers 3 categories in total, total 9 digital I/O module.
1. EM221 digital input extension module
8DI,DC24V (DC input)
2. EM222 digital output expansion module
8DO,Relay (DC24V/AC24~230V) (relay output)
3. EM223 digital mix module
(B) the analog I/O modules
Analog I/O module provides analog input and analog output extension. S7-200 analog expansion module with greater fitness and can be directly connected to the sensor, and a great deal of flexibility, and ease of installation.
1. EM231 analog input module
4AI (voltage or current) input signal ranges set by the SW1, SW2 and SW3.
2. EM232 analog output module
2AO (voltage or current)
3. EM235 analog mixed modules
4AI (voltage or current), the range set by the SW1~SW6
1AO (voltage or current)
(C) communication module
S7-200 series PLC in addition to CPU226 native has two communication ports other than, the other is in the integrated communications, communications with the RS-485 bus. In addition, the PLC can also access communication module in order to expand the number of its interface and the networking capabilities.
1. EM277 module
EM277 module PROFIBUS-DP Slave module also supports MPI from outbound traffic;
2. EM241: modem (Modem) communications module
3. CP243-1: industrial Ethernet communication module;
4. CP243-1 IT: industrial Ethernet communication module, while providing IT application such as Web/E-mail;
5. CP243-2:AS-ⅰ–master module can be connected to up to 62 as-I slave station.
S7-200PLC configuration is made up of S7-200CPU and the extension modules.