Communication Module Connections; Connection - Delta M88 Series Operation And Installation Manual

3.5 Communication Module Connections

The communication module of M88H provides VCC, RS-485, dry contact, EPO,
and Digital Input terminals for different use.
Dry Contact
3.5.1 RS-485 Connection
The pin definition of RS-485 is shown in the following table. Different RS-485
connection requires different set up for the terminal resistor.
• When single inverter is installed, the terminal resistor on its communication
module should be switched ON.
• When several inverters are cascaded, only the first and the last inverter's
terminal resistors MUST be switched ON.
In order to have good transfer quality, twisted-pair wire is recommended to be
used as communication cable.
EPO*1 &
Digital Inputs*6
Figure 3-27 : Communication Module
ATTENTION
Terminal Resistor
VCC & RS-485
39
Installation