Overview
Users can select an RS-485 communication function option for the YS1700 Programmable Indicating Controller. The communication protocol for the YS1000 series is summarized in table 1 below.

This document provides an example application using peer-to-peer communication among YS1000 series instruments with the communication function.

New Function: Peer-to-peer Communication Features
With peer-to-peer communication, up to 32 YS1700 can be connected interchangeably. Four of the connected instruments can each output 4 points of analog data and 16 points of status data.
This makes data exchange and I/O sharing possible since all instruments under peer-to-peer communications can read all data (16 analog and 64 status data).

Maximum no. of connections: 32
No. of receiving units: 32
No. of transmitting units: 4
Transmitted data: 4 analog and 16 status data per transmitting YS1700
Communication interval: 200 ms average (not synchronized to the control computation interval)
Maximum cable length: 1.2 km (when using the conforming cable)

Application Example: Peer-to-peer Communication
Requests have been made for the ability to switch the control mode and perform manual operations on the local panel in a separate location from the main control room. For data exchange between controllers, previously it was necessary to use analog I/O to connect with sensors, bulbs, and other field instruments, but this had the disadvantage that the number of points for connecting these instruments decreased.

By using peer-to-peer communication, the setting value SV, operation output value MV, and other data can be exchanged via communication without using analog I/O. Additionally, you can also exchange data for AUTO/MAN mode switching, control rights among the controllers, and other information.