RelayGo relay contacts
The contacts are made of Silver and Nickel alloys (AgNi) and silver tin oxide (AgSnO2). Other alloys on request.
Depending on the model, a 0,2 μm or 10 μm gold-plating is added to ensure high conductivity and allow switching low level loads in corrosive ambient.
The distance between contacts (GAP) and the speed of contacts opening will determinate arch length and duration. In VAC a 0,5 mm gap is enough to eliminate the arch. In VDC is critical to manage contact distance (GAP) depending on the current and voltage. See the tables for each relay “Maximum VDC current”, as well as special DC applications.
RelayGo manufactures different contacts:
Contacts in series: Two or three contacts in series are equivalent to multiply the GAP increasing VDC cut.
Contacts in parallels: Cannot switch higher loads but increases current stability and reliability.
Twin contacts: The blade is divided into two parts, each with its own contact, both contacts press down each on
their own independent fixed contacts. This system is particularly good for reliably switching at very low levels
(increasing MTBF).
Double break contacts: The double break contact arrangement is equivalent to two contacts connected in series. The maximum intensity supported corresponds to only one contact. This system allows for higher DC operating voltages.
This system prolongs contact life by inhibiting or reducing the arch. In parallel RC suppressors or varistors can be connected. In VDC applications with inductive loads, a diode must be placed inverse, in parallel (Free-Wheeling). Typical contact RM and RQ series resistance is 50mΩ. This resistance depends on materials used, pressure among them and contamination.
Maximum voltages are referred to contacts poles and between contacts and coil, complying with EN 60947/4/5 and VDE 0110 established maximum values, considering pollution, insulation material quality, shape, position and dimensions.
Maximum current is referred to each model, considering stable conduction (Ith) in VAC Maximum power indicated is the maximum switching value contacts can support. This value can be limited and not always meet the maximum power obtained by multiplying maximum voltage with maximum current.