Getting a good electrical connection with the Renogy 30 amp PWM charge controller

[anm]

I have noticed a problem using the Renogy 30 amp PWM charge controller. The compression screws that clamp onto the wires from the solar panels and batteries can be difficult to tighten. Looking closely at the charge controller, I could see the screw heads recessed in the green plastic insulators, but the holes in the insulators can prevent the screwdriver from seating fully in the head of the screw and can subsequently prevent you from being able to tighten the screw as much as is needed.

This is the Renogy 30 amp PWM charge controller:

and in this picture you can see the screw heads recessed into the green plastic insulators:

Just make sure your screw driver fits in the holes in the green plastic insulator, otherwise there's a possibility of not getting the connection tight enough. Bad connection + high current = heat...

 

[Zil]

yes. proper tools are important. spend a buck.

 

[wagoneer]

the voltage is fairly low but constant so do not overtighten these entrylevel charge controllers they are what they are. very difficult to repair.

 

[SternWake]

I really dislike these types of wire receptacles. They always seem to cause an issue at some point.

Crushing stranded wiring requires they they be retorqued after a period of time. Since the terminals are justheld onto a circuit board with solder, one cannot use a lot of torque or risk breaking the tabs on the solder board, which might not be apparent until oxidation sets in and wreaks havoc on the connection

I've taken to tinning the ends of stranded wire on problem terminals that always seem to loosen up, But this can lead to issues when the solder wicks up the wire and reduces flexibility.

 

[anm]

...
I've taken to tinning the ends of stranded wire on problem terminals that always seem to loosen up, But this can lead to issues when the solder wicks up the wire and reduces flexibility.

That's what I do too but on all of them. It keeps all the little strands together, reducing the possibility of one not going in the connector and becoming a potential short-circuit.

 

[Optimistic Paranoid]

You could use a GOOD crimping tool and REALLY GOOD butt connectors to splice an inch or two of SOLID wire to the end of your stranded wire.

Regards
John

 

[Zil]

There are little shouldered plates as part of these screw connectors. Some older ones just have washers. If the stranded wire is not oversize, and placed under the washer-plate, you will have a good connection. All connections feel the vibration of movement and will need to tighten as part of General Maintenance.

 

[wagoneer]

harnessing power from light is not hard a simple connection felt by connecting is easy, do not make it difficult as you cannot "f" up.

 

[anm]

harnessing power from light is not hard a simple connection felt by connecting is easy, do not make it difficult as you cannot "f" up.

I wouldn't be too sure of that... lol

 

[wagoneer]

not a big LOL fan but why snot

 

[Spaceman Spiff]

Has anyone tried threadlocker on the threads to keep them from moving? I'm thinking locktite blue (medium strength and just a dot), so one can still turn the screw if required. A lot of electricians will use a dot of red on connections and pots on circuit boards to keep them from moving (and to see if someone was jacking with the settings).

-- Spiff

P.S. would keep screw from turning, but wouldn't help if the wire is moving under vibration. Possibly very judicious use of solder on the wires. Have to ask an aero engineer what they do next time I see him.

 

[anm]

Has anyone tried threadlocker on the threads to keep them from moving? I'm thinking locktite blue (medium strength and just a dot), so one can still turn the screw if required. A lot of electricians will use a dot of red on connections and pots on circuit boards to keep them from moving (and to see if someone was jacking with the settings).

-- Spiff

P.S. would keep screw from turning, but wouldn't help if the wire is moving under vibration. Possibly very judicious use of solder on the wires. Have to ask an aero engineer what they do next time I see him.

Yeah, I think the problem is not the screw loosening, but the connection loosening due to the lose strands compressing and differential expansion between dissimilar metals. If the strands are soldered prior to clamping with the screw, the wire is lot more solid, but the solder is still soft enough to give way under pressure, it makes for a better connection.

 

[highdesertranger]

I would say you are using the wrong size screwdriver. I don't care for that type of connector either but you have to do what you have to do. highdesertranger

 

[Bela's Mom]

When I first installed mine, I used a small screwdriver and the wires stayed put. After I moved the controller to a different location, I believe I used a driver with a Phillips bit. Later, I found the negative wire out of the controller. The driver is too large to fit down into the hole for the terminal so I did not get the connection tight enough.

Thanks for posting this for others who have this controller. I found out the hard way, however, it has caused me to check connections before turning on my solar equipment so that I can make sure everything is tight and works properly.

 

[anm]

I've already posted this once bu it seems to have gotten lost so at the risk of being repetitive here it is again:

The problem I was seeing is that the recess in the screw heads is for a #2 Philips, but the diameter of the #2 Philips screwdriver shaft is larger than the hole in the green insulators. As I tighten the screw up the green insulator pulls the screwdriver out of engagement with the screw head. I ground down the shaft of a #2 Philips screwdriver so it fit in the green insulator and it works as it should.

Anyway, just make sure you don't have this problem...

 

[anm]

When I first installed mine, I used a small screwdriver and the wires stayed put. After I moved the controller to a different location, I believe I used a driver with a Phillips bit. Later, I found the negative wire out of the controller. The driver is too large to fit down into the hole for the terminal so I did not get the connection tight enough.
...

That is exactly what I was seeing!