It all depends upon if the Diocese or Archdiocese considers bells an instrument or a liturgical tool. The Instruction on Music in the Liturgy from Vatican II,
Musicam Sacram only prohibits the solo playing of instruments during specific seasons.
**65. In sung or said Masses, the organ, or other instrument legitimately admitted, can be used to accompany the singing of the choir and the people; it can also be played solo at the beginning before the priest reaches the altar, at the Offertory, at the Communion, and at the end of Mass.
The same rule, with the necessary adaptations, can be applied to other sacred celebrations.
- The playing of these same instruments as solos is not permitted in Advent, Lent, during the Sacred Triduum and in the Offices and Masses of the Dead.**
If the diocese considers the bell during the consecration an instrument, it is to be prohibited. If it is simply seen as a liturgical tool to draw attention to the consecration, it may be allowed. Hand bell choirs, as they are an ensemble of instruments, do not fall under this prohibition, as they are playing together. This prohibition also covers solo piano or organ playing, a fact which many churches seem to miss.
In all honesty, it is simply up to the discretion of the Bishop, as the Instruction does not make specific mention of instruments during the Consecration.
I have always followed the rule of thumb: When in doubt, ask the diocese. We must have faith that they know more than us and know what they are doing.