I am using my arduino to automatically change water of my aquarium. The program runs fine, the pumps, heaters and valves are controlled by relays. When connected to my laptop, I can see via the serial monitor it works and goes trough the program well. But now my LCD gives weird symbols after switching the relais on/off. I have read quite some questions and answers already about these problems, but no univocal clear answer.
My main question: Can the disturbance also come due to the 'physical' distance from the lcd to the relais?
As you can see, the arduino is right above the relais, next to a 24V DC power supply for the valves, and the switch-plugs are connected to the relays. The relays will switch 2 pumps (30W) but also a heating elements of 300W.
My question: Can the weird symbols only be caused by current trough wires like discussed in this topic? Or does the 'physical' distance also cause troubles?
Also: these relais I thought were Solid State Relais but probably are not, since the same webshop is selling 8-relay board named as Solid State Relais as well:p. might that give me a solution? Here a link to the schematic of the relays I'm using now: schematic. (Considering that since I saw this comment in the topic linked above):
Look at the datasheet for the "Relay". The input to the relay is actually driving a tiny SSR, which switches the actual power to the relay itself. Since the input to the relay thingie is a SSR input, I don't see a diode really doing anything
If anyone can help me with this problem would be great, I've already read quite a lot about these problems, but don't understand how to solve it. If it is fixable with capacitors, resistors or snubbers, please attach a little drawing with it if possible. Thanks for the time everyone!