Choosing between silver and gold electrical contacts is often a simple one, generally the selections is based on the current that the switch is required to handle. Most of the applications for Precision Sensors pressure switches fall into one of the following two categories:

Applications switching from 1 to 5 Amperes: These applications would include smaller motors, actuator solenoids or even a lighting load. Applications like this require a switch that can handle the electrical load, both at the time of contact transfer and for continuous duty. The contacts must be capable of dissipating the heat generated by carrying the energy. The contacts must also be able to transfer the load without sparking or arcing. In these higher load cases the preferred contact is a silver alloy contact.

Applications less than 1 Ampere: These applications include digital logic circuits, programmable logic controllers, relays, LED lights and other low power devices. In these cases there is much less power being transferred across the contact and the chances of arcing, sparking, and heat related problems are reduced. In these cases, a gold contact is the preferred choice. Of special interest are applications where less than 50 milliamperes are being switched. In these cases the ability of the switch to have minimal impedance to conducting electricity are important, as such the inherent ability of gold to resist oxidation makes it a more suitable choice than a silver contact.

There is another case of interest, in which the user would like to switch a larger electrical load that will draw more than 5 amperes, such as a large motor or a heater. In these cases a relay is recommended to transfer the higher load and the sensing switch can be used to trigger the relay.

If you need further assistance in choosing a gold or silver contact in your switch please contact Precision Sensors engineering department for further assistance.

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