For this function, before starting to measure the flow rate, the user sets up a certain fixed unit of flow volume first, a pulse output will be delivered when the fluid flows by this certain unit of flow volume. This technology makes flow monitoring and measurement more reliable.
When LORRIC considered the pulse errors between high and low speeds, a significant variation rate was noted especially between medium and low speeds (0.15m/s~1m/s). For instance, where only one pulse should have been output, two pulses were instead. To correct such errors in pulse structure, we designed a market-unprecedented impeller pulse output method using unique software logic: "Pulse V2.0 Constant Volume Pulse Output." It allows users to select a fixed volume (volume unit options: L, US gal, Imperial gal), and for every unit volume that flows through a three-way pipe, a pulse is output to the host (for example: 1 pulse per 1L), as illustrated in the animation.
By changing the perspective to software computational logic, LORRIC achieved the operational principle of Pulse V2.0: Assuming 1L triggers 1 pulse, originally an impeller rotation of 180° would emit one pulse, which can also be adjusted to emit a pulse every 90°. The software can determine the flow rate based on factors such as rotational speed, then calculate the volume flow rate, and finally decide the degree of impeller rotation needed to output one pulse. The LORRIC impeller flow meter can adjust the output signal frequency according to the calibration function, for example: at slow flow rates, 5°=1L; at fast flow rates, 90°=1L. Pulse V2.0 can directly use the rotational speed to determine the degree of rotation for output, with the resultant data matching the cumulative flow on the machine.
Pulse V2.0 can judge under different flow rates, using different rotation angles for adjustment, and can set how much unit volume a single pulse represents within a reasonable range given by LORRIC (depending on the pipe diameter difference). We can also say that using a certain unit volume to represent a pulse makes the numbers relatively easy to understand and communicate, such as: 0.01L per pulse.
Compared with the traditional impeller flow meter pulse output method, the machine provides users with a K value to calculate. Assuming there are approximately 7.7 pulses per L, this value can be set on an external pulse-calculating machine. By dividing the received number of pulses by 7.7, the flow volume in liters can be calculated. However, in reality, the slower the flow speed, the greater the friction, causing the error correction curve to vary, and the signal frequency becomes too low to calculate accurately. Hence, the K value at high and low speeds is not quite the same, leading to larger measurement errors.