by ober » Sun Jun 05, 2011 11:41 am
I don think you can control 6A using the existing component and PCB of PR11.
1. To control high ampere load, the transistor must be able to support more than that current, 6A must atleast require the transistor Ice (collector to emitter) to be atleast 12A, because it will dissipate heat, and will further damage the transistor in long term. Not to mention that the current design is not meant for 6A of look, do check the spec of transistor use in PR11 as suggested by yonghui.
2. The PCB track of PR11, it must be wide/big enough to sustain 6A or more for continuous running. Current design does not carter for that.
You will need change to higher switching transistor/MOSFET and create your own PCB with larger track.