How can I connect to a Yokogawa YS1700 controller?

To communicate with the Yokogawa YS1700, the following steps can be followed:

Ensure that the Modbus TCP/IP Ethernet driver is installed - if not, modify your TOP Server installation to include the Modbus Suite (click here for a how-to video). If you don't have TOP Server installed already, you can download the latest version here.
Add a new channel using the Modbus TCP/IP Ethernet driver.
Add a device to the Modbus Ethernet channel. You'll need to (for settings not specifically referenced below, you can keep the defaults):
1. Address the YS with a ".1" after the base IP address. For example, if the IP address of your device were 192.168.10.20, you would enter the following as the device ID in TOP Server - 192.168.10.20.1
2. Check to confirm what the "dreg2" setting is in the Comm. menu of your YS1700:
  1. If "dreg2" is at the default of "H-L", you will need to uncheck/Disable the "First Word Low" Data Encoding setting in the server's Device Properties.
  2. If "dreg2" is set to "L-H" instead, you can leave the "First Word Low" setting at the default in TOP Server.
Set the PV/SP/MV and Mode address as Long data types (a 32 bit format) in the YS1700.
Set the SV1 address in registers 40013 and 40014 of the YS1700. When setting the TOP Server tag addresses, use the first register. Users should be aware that TOP Server adds an extra 0 to accommodate newer Modbus devices with a larger range of offsets. For example, "40013" becomes "400013" - these are functionally identical (for more details on Modbus addressing in TOP Server, click here).

For a list of Modbus register addresses available in your YS1700, refer to the controller's help documentation.

The Yokogawa YS1700 is a newer controller that replaces the Yokogawa YS170. It supports Modbus TCP, so the TOP Server Modbus TCP/IP Ethernet driver can be used to read and write variables in this device.