Why do we ring the bell  when the Harati (Arati) is given  to the God ?

In the Temples , the bells are  rung  many times at the time of offering

Naivedyam (Prasadam), prayer for awaking  in the morning  timings,

when the temples are closed, and the Harati is given to the Deities and Gods.

The meaning for ringing the bell, the evil spirits and wraiths will go

 away at that time and also inviting all the Deities to the temple at that time.

The God reaches to the Idol with the supreme part (Amsa) at the

Harati time, and not only that all the Devotees should  have the darshan

of that Supreme Amsa reaches from the God and have the feelings of

blessings from Him. So at that time in the light of that Harathi the

 Devotees can see the Lord with ecstacy.  The ringing of the bells

 are called as Jaya Ganta ninadam.