MIKROE-551 mikroElektronika, MIKROE-551 Datasheet - Page 21

• Manufacturer Part Number: MIKROE-551
• Description: Development Boards & Kits - AVR AVRPLC16 V6
• Manufacturer: mikroElektronika

Specifications of MIKROE-551

• Rohs: yes
• Product: Development System
• Tool Is For Evaluation Of: Atmega32
• Core: AVR
• Interface Type: Ethernet, RS-232, RS-485
• Operating Supply Voltage: 16 V to 30 V
• Description/function: AVRPLC16 v6 board only, Telit GM862-GPS module with antennas and cables, UTP Cable, CAN-SPI board, MMC/SD card are sold separately
• Dimensions: 265 mm x 220 mm

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AVRPLC16 v6
12.0. Relays and optocouplers
Industrial devices usually consume more power than the microcontroller can provide via its I/O ports. To enable the
microcontroller to be connected to such devices, the development system is supplied with 16 relays by means of which
it is possible to provide up to 250V power supply voltage. Each relay has one normally-open (W0, W1...) and one
normally-closed (NW0, NW1...) contact. Sixteen relays are divided in four groups each consisting of four relays. Relays
of one group are connected to one common contact. Accordingly, there are COMA, COMB, COMC and COMD common
contacts. Figure 12-3 illustrates the connection between one group of relays and their common contact COMA. In
addition to relays, the development system also features optocouplers whose function is to galvanically isolate signals
supplied on the microcontroller inputs by industrial devices. As can be seen in Figure 12-3, the optocouplers are also
connected to one common contact OCVCC.
Figure 12-1: Relays with connectors
Figure 12-2: Optocouplers with connectors
In order to enable optocouplers’ inputs, it is necessary to set switches 1-8 on the DIP switch SW5 to the ON position. To
enable relays, it is necessary to se switches 1-8 on the DIP switches SW7 and SW8 to the ON position.
Figure 12-3: Relays and optocouplers and microcontroller connection schematic
MikroElektronika