Grade 1 Contacts

Suitable for use in Ungraded and Grade 1 systems. These contacts meet the minimum reqiuirements for Grade 1 Systems, they have no tamper and are not required to be potted/sealed and have no magnetic detection.

Grade 2 Contacts

Suitable for use in Ungraded and Grade 2 systems. These contacts are required to have a mechanical tamper and or be potted/sealed. End of Line resistors are an option but are not a requirement to meet Grade 2.

Grade 3 Contacts

Suitable for use in Ungraded and Grade 3 stystems. These contacts all have the properties of Grade 2 contacts, but additionally are required to be either immune to magnetic attack, or shall detect the introduction of a rogue magnetic field and generate a tamper signal to alert the system of attack. The specification of these contacts in the higher security systems does dictate reduced operating gaps and tighter tolerances.