On call CCTV IP camera service-Hyderbad

Hi, we have few installation of IP cctv in hyderabad. We need on call service engineer for attending any service calls. Service calls can be on sunday or on any national holiday also, it needs to be attended.
Location - Hyderabad
Requirement- CCTV IP Setup maintenance
Time - 1 yr on call
Reimbursement- Per visit per service call