Although vacuum switches have been around for more than a century, many users are not aware of their features; therefore they are unable to find the right industrial switch for their applications. This article helps you in identifying some major parameters for determining the appropriate industrial vacuum switch whether you are opting for pressure switch or a vacuum switch:
A determining factor to consider while looking for industrial switch is the pressure or vacuum switch which is the range at which the application functions. The electrically operated device is required for controlling the flow of gases and based on the pressure gauge, the type of switch should be chosen. Sometimes, you may require different set points depending upon the pressure the application is set in. It would, therefore, be advisable to seek the professional opinion prior to taking a final purchase decision.
Adjustment of Set Points
Of course, determining the optimum set point for the application may be easy, but without the knowledge of ascending and descending pressure or vacuum, you might make a mistake sometimes. Further, you should be able to decide when the set point is reached, whether you desire the switch to remain open or to be closed. Further, sometimes, the option of selecting single-pole or double-throw switch may also pose a challenge for the application.
In case you are not very sure about the field adjustability, it is always prudent to have the option open. If you are sure of the set points appropriately, you can go for factory preset points with field adjustability, which is normally suitable for OEM applications. In the case of factory-set points, the option of readjusting the set point is ruled out.
The “On” and “Off” switches or the calibrated switch is another option you should decide depending upon the application. If you are unsure, it would be advisable to go for both the options which will also be economical and avoid the complicated circuit in the switch.
In any case, your objective is to ensure that the vacuum switch pressure is equal to or more than the frequency of operation.
Depending upon the process media which will be in contact with i.e. air, water, acid or hydraulic fluid, the wetted material is decided. Another determining factor is the outside environment in which the switch functions and the range of temperature at which the application functions.
Other points of consideration would be—-the external environment i.e. an indoor or outside application and whether the switch can be encased in a panel box or will it be exposed. If so, whether the specified type of enclosure as per the statutory guidelines would be required for the application?
Electrical operations such as AC, DC and voltage, amperage, etc. would also determine the pressure or vacuum switch. If the interface of the electricity is a relay, the inrush spikes also might result in something which should not be under-estimated. It is also not a bad idea to decide what type of interface is required.
In case you desire to have certain special requirements, you need to specifically mention this to the service provider. Any value-added options spelled out in advance would be better—like a specific brand of the connector or any such other supplementary items which will benefit the application. Of course, you cannot expect the add-ons without additional cost.
The life of the switch depends upon the frequency in which the switch is activated, system downtime and the overhaul schedule. It is an accepted fact that diaphragm switches last for long and the piston type and bellows switch respectively.