Note that the TMCC Direct Lockon will kill the DCS signal. If you're running MTH DCS, the Direct Lockon is not recommended. You can use it if you put it behind the TIU on the input side, but it's really redundant as the PH180 has an excellent circuit breaker, and the TIU has a TVS protection diode across the outputs.
If you don't ever plan on running DCS and have no TIU, ignore this comment.