Hi everyone,
I appreciate your help and input to the following problem:

My well water pump was recently replaced by a well pump contractor.
He installed a 1 HP submersible pump with a cycle stop valve (rating not known), new presure switch, and pressure guage.

The cut in and out pressures were set at 60psi and 75psi respectively.

I noticed that as I opened a faucet, in 5-10 seconds, the pump turned on when water pressure droped below 60psi. It then turn off after a few seconds because the pressure quickly went up to 75psi.

I read on the existing tank label that it was precharged at 30 psi, and that the pump pressure switch should be set at 30 psi.

My questions are:
1. Was the pressure switch correctly set? the CSV did not seem to work properly, in my opinion.

2. Should the tank precharge air pressure be reset to 50psi or other value?

3. With cut-in and cut-out pressure set so high, is there the risk of rupturing the membrane or blader?

What would yoy recommend me to do to correct the problem?

The contractor insisted there is nothing wrong with his installation.

Thank you for your help.