TP-Link T1600G-18TS Configuration Manual page 274

Configuring Spanning Tree Configuration Example for MSTP
Figure 5-11 Configuring the Priority of Switch B in Instance 1
5) Choose the menu Spanning Tree > MSTP Instance > Instance Port Config to load the
following page. Set the path cost of port 1/0/2 in instance 2 as 400000.
Configuration Guide 251