My pump does not alarm and it's not visible, so I rarely have a problem. There is no more reason to alert the TSO to the pump than to alert the TSO to any other item which may lawfully be transported, it only causes delays. Frankly, when I first got the pump and did mention it, I had several TSO's tell me that they wished I hadn't because they now had to do a pat down. If there is a pat down, there is nothing wrong with the pump and you will be on your way quickly.

There are always a few poorly-trained TSO's out there and if they give you a hard time, don't be afraid to ask for a supervisor.

Lastly, as a backup, you should always travel with copies of all of your prescriptions, including for your pump.