Flow Switches- How to Install and Test a Flow Switch?

A flow switch, sometimes related to a flow sensor or flow indicator, is a tool used to control the flow rate and pressure of liquids, air, or other gaseous media by a duct, system, or loop.
These switches or sensors can control flow over a given space or set up to constantly prevent total flow. Technically, a flow meter or notice may not certainly be a proper flow switch – if the tool only records and displays data, it is more suitably called a meter or indicator.
In most states, though, they will trigger effects or prevent or start other parts elsewhere in the system – pumps, such as altering the flow rate and pressure to the aspired and programmed levels. This is then an exact flow switch.

How does a Flow Switch work?

To know how a flow switch runs and what it does, it is helpful to outline the core elements that make up a standard switch or sensor of this sort.
Many kinds will hold a paddle or magnetic trigger of some kind (the primary device) attached to a circuit and put in the channel by which liquid or gas is passing. This paddle is removed or switched by whatever material is passing by and sends a signal reading back to a trivial element known as the transducer.
The transducer takes this raw sign from the paddle and crosses it onto a transmitter in a readable form. The conductor, in turn, regulates this reading against a predefined set of parameters and functions whatever sign or action is needed to adjust the way of elements and tools elsewhere.

In this way, flow switches can control, record, and regulate the flow rate of liquid or gas through a specific part of a system, or the entire system, assuring flow stays within those pre-set parameters. Suppose the velocity passes or drops below what is needed. In that case, it can directly trigger a range of actions such as initiating an alarm, powering on a pump, engaging flow, shutting off parts of the system. These actions switch functions will rely solely on the kind of switch and what it has been designed for.

Not all flow switches will have a physical paddle as such. Ultrasonic and other non-intrusive accounts are also fairly basic, which work by ousting a signal back off the medium being controlled. This is particularly useful when the means are infected, physically damaging, otherwise threatening, or helpful to have no moving parts shown to natural wear and tear.
Rotaflow or Variable Area Flow Sensors are more simple tools that use a tapered tube with a cork (or sometimes an electromagnet) to regulate, limit or let the free passage of gas or fluid by. Different kinds of magnetic flow switches are available, and they can be very efficient in various uses as long as the means are somewhat conductive.

How to install and test a Flow Switch?

Because there are so many distinct types of flow switches, as we will see in the following divisions, there is also a vast array of flow switch fitting techniques and methods. When viewing data on how to wire a flow switch, the most crucial thing is to know which kind of switch you are using and for what intent.
Some primary rules of thumb are used to most flow switch installation systems, however. These involve:

  • Installing flow switches on a vertical section of pipe or duct
  • Assuring there is a reasonable length of straight pipe both in front of and behind the switch, ideally, the equivalent of 10x the pipe’s width
  • Avoid fitting or process a flow switch near curves, other parts, valves, drains, more serious or more general parts of the pipe, and any other traits that might cause apparent changes in flow rate by this area


Choosing the exact type, size, voltage, and purpose of the flow switch for the specific purpose you are placing is crucial if you work correctly in the part you need them to act.
With such a wide array of products and brands available, it can be a complex field to operate, which is why we are always pleased to give direction and advice through our many support courses. Drop us a line any time with inquiries or queries. Our specialist team will be able to lead you on the right path.