Buchholz relay positioned between conservator tank and tank cover. If some fault occur in transformer (short circuit between winding layers or turns, deformation on insulation materials etc.), various gases are released. These gases rise up due to their density and accumulate in the buchholz relay. And switches in the buchholz relay is actived due to this accumulation.
There are two 5 Amps electrical contacts into the relay. Any signalization and monitoring system can be controlled by electrical contacts in buchholz relay.