Instructions Manual of Communication Interfaces MI485 / MI486 / MI488
3
1
DESCRIPTION
1.1
MI485
The MI485 communication interface converts an RS485 signal to an RS232 signal and viceversa. The signals are electrically
isolated. The communication interface is designed for connecting instruments with RS485 communication to RS232
communication (a PC, PLC, etc.). The MI485 interface with corresponding equipment enables setting and reading the instruments
with communication rate up to 115.2 kbps.
1.2
MI486 AND MI488
MI486 and MI488 communication interfaces are designed for connecting the instruments with RS232 or RS485 communication to
ethernet network. They enable connection of the instruments with a PC via ethernet network. The signals are electrically isolated.
The interfaces are designed only for reading data from intruments (with corresponding software). They enable communication rate
up to 115.2 kbps.
2
CONNECTION
2.1
MI485
Three groups of terminals should be connected to the MI485 communication interface:
•
Auxiliary power supply: It is connected to terminals 13 and 14. Auxiliary voltage value is written on the interface front
label.
•
RS232 communication: Connect it according to the table below. Maximal length is 3 meters.
MI485
Computer – DB9
Tx (26)
Rx (2)
Rx (24)
Tx (3)
GND (25)
GND (5)
•
RS485 communication: It enables connection of up to 32 devices. The line should be terminated with a 120
Ω
resistor.
Connection is made according to the table below.
MI485
RS485 instruments
A (21)
DATA +
B (23)
DATA -
After connection to power supply voltage, the Power LED indicates the presence of supply, while diodes Rx and Tx indicate data
transfer.
2.2
MI486 AND MI488
Three groups of terminals should be connected to the communication interface MI486 or MI488:
•
Auxiliary power suppy: It is connected to terminals 13 and 14. Auxiliary voltage value is written on the interface front
label.
•
Ethernet connection: Connect the ethernet cable to 10/100 RJ45 terminal on the communication interface and connect it
with ethernet network.
•
RS232 communication (for MI486): Connect it according to the table below. Maximal length is 3 meters (
CROSS-
OVER cable
).
MI486
RS232 instruments
Tx (23)
Rx
Rx (21)
Tx
GND (22)
GND
•
RS485 communication (for MI488): It enables connection of up to 32 devices. The line should be terminated with 120
Ω
resistor. Connection is made according to the table below.
MI488
RS485 instruments
A (21)
DATA + (A)
B (23)
DATA – (B)
