3.Interface definition
3.1 Power interface definition
Users can choose
⑥
DC power interface,using the power adapter supply with the interface of the 5.5mm outer
diameter , 2.5mm diameter ;
Also choose the VCC and GND terminal power supply, only choose any one of the power supply is OK;
E90-DTU can use 10 ~ 28V DC power supply, but it is recommended to use 12V or 24V DC power supply.
3.2.RS232 interface definition
The E90-DTU can be connected to the device via RS-232 using the standard DB-9 interface.
3.3.RS485 interface definition
E90-DTU can connect the 485_A terminal and 485_B terminal with the device RS-485 A terminal and B terminal.
Pin NO.
Definition
Function
Description
1
VCC
Pressure line power interface, positive
10 ~ 28V DC, recommended 12V or 24V
2
GND
Pressure line power interface, negative
The power supply negative pole is connected
to the system ground and the housing
3
485_B
RS-485 interface, interface B
The RS-485 interface B is connected to the
device interface B
4
485_A
RS-485 interface, interface A
The RS-485 interface A is connected to the
device interface A
★
Note: The transceiver will be poor communication when connecting multiple devices , while connecting a single device
is not, please try to parallel connect 120
Ω
resistor between 485_A terminal and 485_B.