I've recently taken over a project that a friend started, to measure and adjust several parameters for indoors hydroponics. The general idea is to have several sensors (ORP 1130 for pH/ DFR0300 for conductivity for example) which require 5V input voltage linked to an Arduino Mega and to VMA447 peristaltic pumps, there are 6 pumps in total
My friend used this 5V 18A power supply : Mean Well Power Supply 5V 18A 90W LRS-100-5 - ProtoSupplies and noticed that the voltage in the sensors (ORP 1130 for pH/ DFR0300 for conductivity) was not 5V as it should have been but rather between 6 and 6.5V. He suspected that was because the generator had too much input current and it increased the voltage.
This is quite a big issue because the voltage is not stable and it affects the pH measurement.
That's why he had the idea to use 5V voltage regulators to maintain it to the right value. I've been browsing for the right regulator when I realized that the VMA447 pumps require "6V/5W".
I read several topics about that before and know that you should always use the input voltage required and at least the input current. But I know that some devices tolerate a difference in voltage, so do you know if that's the case with these pumps and I can use a 5V input voltage? Or I need to change either the power supply or the pumps?