I use an Animas pump. When I change the set, I go through the following steps
- attach a new cannula
- rewind the pump
- load the cartridge into the pump
- prime (fill the tube)
- attach to the cannula
- fill cannula
With this, the only way insulin can get into my body is if I over fill the cannula (the last step).
Alternatively, is it possible that your post set change hypo is caused by something else?
For example, is your insulin going "off" in your pump so not as strong and when you change it, you are using "stronger" insulin?
I think this could happen if the insulin gets very hot.
It is not something I have experienced but I guess is more likely in hot weather.
Sorry, I cannot think of anything else which may be causing your hypos ... but, there again, I am not familiar with your pump.