You can easily assume that all flow meters in the market have a pulse output. However, that is a feature that is absent in some flow meters. The reason for the presence or absence of the pulse output is your desired results after you gauge your fluid flow rate.
Like other meters, a water meter with pulse output has several classifications. Manufacturers use velocity or displacement to classify the pulse flow meters.
Five flow meters produce pulse output. Each of the meters has an output that directly relates to the flow rate from the flow meter. The meters are Reed switches, Hall Effect transistors, Namur sensors, Ultrasonic devices, and Optical sensors. All of them use a gear or a rotating turbine. It indicates that they are all mechanical flow meters since they have moving parts.
Hall Effects Transistors
If you want a device with a long life span, great stability, and works at high frequencies, then you should consider the Hall Effects transistor. They are solid-state transistors. Also, they allow power to pass through them in a single direction. The process activates when it passes through magnetic fields.
A typical transistor will have three wires. Each year will need a 5 to 24 VDC Power supply. On the other hand, the resistor will be 10kOhm.
The device will have a sinking and sourcing sensor. The sinking sensor will have a pull-up resistor through the pulse output wire and the positive power.
When the sinking transistor is inactive, the energy flows past the pulse output through the resistor. The transistor lowers to zero volt wire When you activate it with a rotating turbine or a gear embedded with a magnet.
You can activate reed switches the same way as you do with hall effect transistors. Reed switches are devices you can use to connect and disconnect input and output. That means you need a magnetic field to pass through them.
In this case, you will need two wires instead of three. Also, you can operate with lower power than hall effect transistors. If the application is hazardous, you can use a battery with no power supply.
You should note that reed switches are mechanical devices. Therefore, we are not suitable for high Frequencies. Also, they have a shorter lifespan compared to hall effect transistors.
NAMUR sensor is one type of proximity sensor. They operate in a normally open or normally closed setting. Also, you can get them as magnetic, capacitive, inductive, or photoelectric sensors.
These proximity sensors were made for use in hazardous applications. Thus, you will find them where there’s dust, fiber, and explosive gasses.
Proximity sensors have closed and open output conditions. However, this is not present in a Namur sensor. The sensor will produce a current output level to match the target position.
The Namur sensor will limit the current flow. Therefore, there are no chances of ignition in an unsafe atmosphere.
These are the only non-mechanical pulse flow meters you will find in the market. Therefore, the snow will not have a real pulse. You get the floor against an algorithm that indicates the flow rate at that instance. You use the number you get from the algorithm as the pulse input.
Optical sensors are commonly used alongside turbine flow meters. We have the power to offer high low flow performance in uses involving clean fluids. The optical sensor uses infrared wavelength. The rotating turbine blocks the light from the source. Some light passes through as the turbine continues to rotate. The sequence creates signals that indicate the speed of the fluid. In this case, you will not need a magnet to detect the pulses from moving fluid.
Since you don’t need a bulky sensor, it makes an optical sensor suitable for low-flow performance.
You can use water meters with pulse output in all applications. All you need is your field’s needs before you settle for one. Contact your supplier for advice on the best device for your firm.