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GT - How to properly wire RS485 - 2 wire communication

Issue:
Although most of the customer use 2 wires for their RS-485 2 wire protocol, the actual standard is called for more.

Product Line:
All GT series

Environment:

Cause: 
Not fully understand the 2-wire protocol

Resolution:
Since the inverters are outdoor products, they can be installed at any environment (According to there NEMA Rating). Because of this, the modbus device in the inverter or customers monitoring system will most likely be expose to Electro Static Discharge (ESD). In order to protect the equipment, it is highly recommended that a twisted pair cables be used (Belden cable). Instead of two copper wire, it is also recommended that there should be at least three copper wirea. The Belden cables normally came with shielding and a drain cable. 
1. Two wire are connected to data + and data -
2. The third copper cable is connected between the inverter signal ground on the modbus device and the customer device.
3. The drain is to be grounded to earth from the monitoring side only.
 
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