I am just getting into this great forum so I am excited to share with all of you and help where I can.
We took ownership of our homestead in March, in the highlands near the North Shore of Lake Superior. It has an existing solar installation that I want to fully understand before making any alterations or updates.
The white charge indicator component is making a clicking sound every few seconds or so, which suggests a relay and I am guessing some sort of error condition. I am an electrical engineer by trade, so I understand the essentials of solar but I am just learning about the various components and their role. The click is especially urgent because my wife and I sleep nearby
Pat, do you have any more info on the charge controller model and maker. The device looks like a system meter display. Some charge controls can be bought without a case and put in one by an owner or manufacturer and i can not read the nameplate in the photo.
If there are little to no settings adjustable by the operator, then it could just be failing, i will need to see the specs and know more about the clicking.
Usually if a relay is clicking during early morning, intermittent or heavy overcast, is correctable through the mppt settings in the control. You can pm me on this site. I am an installer in michigan and we have an off grid customer in the up that i am going to go to soon in order to spec a windmill and other upgrades. We can square it away on the phone and if you need someone sooner call dave camps at blueterra energy, copper harbor, but he goes all over the up. Dave will charge, but if i can help other permies folk, i do it free, especially if i dont have to go thère from the lower peninsula.
Ok, i see. It is a display. Never seen that one. Maybe just turn it off until you need to see it or disconnect/replace it. I was confused because some people on this site are not from north america and use names for equipment that can be confusing. I re-read your post and realized the mistake.
Here is the inside. The two relays on the right are constantly clicking on then off every few seconds. The LED on the little logic board at the top left will go on or off with each toggle as well.
Also, now when the inverter is on it constantly goes into "overload" although when I disable this unit by disconnecting the fuses I am sometimes able to turn the inverter on to get lights and things going.
Any ideas what is happening or how to diagnose further? The big orange cable runs to the batteries and the big black cable to the panels.
That contactor does not look good. It looks like heat to me. I dont know if it is heat from manufacture or what, but it looks to be from operation and you said they were a clickin. In the image, i think i can see a witness mark of vapor deposit above the contacts, far right, on the underside of the boss, could be a reflection/blur.
What does the contactor switch? Can it be manually bypassed or replaced with a switch or wire nut even? What else does the equipment do besides bind circuits and provide a meter and shunt?
Can you omit the thing entirely and fly blind on the meter side?
If you post the make and model, we can find more, so far i got hoffman, interesting back story there... and the blurry c$$&&* seattle wa.
I bet you will pick up some extra usable watt-hours by omitting or updating this.
The good thing is, a person familliar with electronics could easily diagnose and repair this. The value for the contactor coil, and a check of the switching control and other connections, etc. Looks like a ceramic resistor and diode ( blue wires on contactor), and a transistor resisters, etc., clumped on a heat sink (red and white). These areas could be checked.
I am not qualified in electronics, but i can say that you should bypass the contactor and direct wire what is required to keep the inverter and charging equipment connected inside the enclosure. The contact points will eventually fail and may arc catastrophically. It needs a cleanup if not updating. The raw holes with battery, pv and other wiring through burred holes is a worry, although i have done the same for quick, temps and such, and there appears to be no damage to any wires, the engineer in you has to have already wrinkled your nose in there!
I can point you here for great equipment. They have something that you can likely idendtify as replacing and enhancing the function of the failing equipment in your system.
If repair is not practical, i would gut the box of all but fuses, switches, the little distribution block, and the shunt and then mount feedthrough blocks for distribution, fusing and termination on din rail for future circuit additions. If there is room, din components allow flexibility and compact modular accessories for building your own machine panels., this and some specialty stuff from midnite and you can build to suit with inexpensive or existing enclosures.
The brass colored block(s) are meter shunts, they have a specific value and allow prescise measurements of current flow across them. That looks to be your main negative battery bus for the system. There is a terminal block, just visable and i cannot see what is there.
These should be left alone, aside from tracing wires to their terminations and components.
The blue wires with white stripes control the big relay (contactor). If you disconnect one of them or its fuse, the contactor will stop cycling. Is it normally open or normally closed operation?
A main question that i have is, where do the red and black wires from the contactor lead to? What power form are they, ac or dc? What device or component do they connect? You can check voltage on the red and black, it will give you an idea. Most likely dc stuff, but i speculate! Was there not a cronic issue with whatever is connected to it cycling?
I can only guess what it does. Where are all the positives terminating? Hopefully the power issue is corrected by squaring away the relay.
Have you opened the unit and witnessed what is exactly going on? If its the relay to the right as most suspect be making the noise then caution, the pad on that relay is only good for an approximate number of on/off cycles and perhaps one of the contacts is worn. The relay switches live voltage and each cycle a small arc could form worst case when very worn enough heat is generated to melt the box if rabid cycling occurs. Probable an idea to stop the relay switching a load as frequent as it appears from the description.
Relays or their pads also overtime become pitted and uneven contact occurs again helps to create arcs and possible that a relay contact could weld together then a permanent live circuit an outcome.
As for any specific resolution to your problem those trim pots - view on the circuit board- may hold an answer, maybe wear and tear on a relay contact. Any make and model number?
It could also be everything is fine and that the input voltage from the solar system be a problem? Did mention sleep nearby so this problem occurs at night and should be minimal/no voltage to the controller if its dark, although not unheard of for quality panels to generate a small voltage from moonlight.