Would anyone have specifications on the internal dimensions of the electrical connectors of the following MPPT controllers.
100 | 20 and 100 | 50
The Victron equipment is of excellent quality, but IMO the one downside is undersized input / output connector’s.
The connectors themselves are of good quality, the problem I’m having is the connectors cannot handle decent wiring as it physically won’t fit into the ports.
I’m looking at various connectors to solve the problem and think the PTN connector will do what I want, these can handle larger cables with connection to the device by a smaller pin.
I am unable to find technical specifications on the ports used on the various Victron controllers, would anyone know where I could find this, as the PTN connectors come in a large variety of sizes.
Am I the only one who has come across this problem.
You don’t actually need them, the rising clamps work well to grip and spread the cable.
Turn down the charge amps if you aren’t going to size battery cable right though. No one needs a cooked terminal. You are shwoing 6-10mm though that is not undersized?
Are you wanting depth of terminal? The recommendation for strip length is somewhere in the manual.
Hi LX, I am after the actual width of the opening not the size of the cable it can handle, the PTN connectors come in many sizes, ranging in 0.2 to 0.5mm increment size difference.
I would like to get the best fitting connector for each mppt, eg: if the width of the opening is 4.0mm wide, I can get a 3.8mm then next size is 4.2mm wide connector.
This way I get the most contact point and minimise heat building up in the connector due to under sizing.
I don’t want to turn down the charge current I would like these to run at their max all the time, depth is not an issue as these connectors have plenty of depth on the pin side.
I will keep searching as it’s difficult to get an exact size with any ruler etc as the opening of the connector is inset, so can’t measure the right size accurately.
I don’t really like the PTN the insert as the tip gauge ends up being less than the cable inserted.
For example the tip gauge for the one in your post is 1.2*4.2 = 5.04mm
So really you take a 6-10mm cable and make it smaller and also solid, leaving you open to the potential of having to over torque and damage the clamp mechanism and warm terminals.
(I know its a short length, yada yada for all those who like them).
I will purchase some PTN connectors and check the heat generated at the connector and see if it varies from the bare cables.
I am only running a smaller system which max’s out at 50A for many hours in the day, but it can generates enough heat at the mppt connectors to see if using a PTC connector is a good or bad idea.
Your calculation of 1.2mm x 2.4mm = 5.04mm is correct, but the connector I put up as an example has a double folded section on the pin so it’s measurements are 4.2mm x 2.4mm = 10.08mm which is correct as it’s sold as a 10mm2 connector.
When you look at any high current connection they use either Lugs, ferrules, or crimped connectors such as GTLA.
Using bare wire IMO is the poor cousin to a crimped and properly torqued connector, especially in DC higher current applications because of the heat that can build up quickly with lower voltages and high current.
I still stand by my observation of the connectors Victron use are not electrically undersized but physically undersized, they don’t make for an easy insertion of the cables to ensure you don’t cause loss of cable strands when trying to get the cable in as in their manual they recommend the use of high strand count wiring and not wiring with thicker / less strands.
I have played with a number of Chinese electrical equipment over the years and found they tend to err on the side of using larger connections to allow for larger cables to be inserted if required.
It’s only an observation of the Victron equipment, I’m not saying what Victron has done is incorrect, but a connector with larger entry would make for a more secure connection ensuring all the strands make it in there undamaged and a better user experience.
We use pins/PTN on 100/20 and smaller, because in those controllers a 6mm ferrule, although it theoretically fits, its crimped cross section is square, and can require a lot of forging to get the square crimp into the correct ratio rectangle to fit the terminals.
For the larger MPPT controllers, where the spec is 16mm^2 (100/50 etc) you are probably best to use bare wire if you don’t have a ferrule that fits.
@guystewart clarified the ferrule vs no ferrule issue a while back with reference to the wiring unlimited docs and other posts. I’ll try to find that post and link to it.
It seems to me that to ferrule or not remains a decision left to the installer, with the proviso that the installer should know and understand the issues around;
The risk of stress fractures and breakage when thin stranded cable gets soldered into a solid
The risk of fine wires being left out of the terminal (potentially causing shorts) when ferrules are not used
The risk of ferrules creating a situation where terminal pressure is suboptimal.
The risk of heat buildup if a cable’s cross sectional area is drastically reduced (such as PTN/pins as mentioned by @lxonline , or trimming a lot of strands out of a larger cable in order to fit the terminal)
I honestly have never had issue fitting the max cable into the connectors, so there is that.
If it takes 16mm be sure thats what we have used.
16mm is more than enough for 50A continuous and never has anything ‘fall out.’ the rising clamps hold everything well and of you stick to wiring rules and electrical standards of not having unsupported cable for longer than 30/40cm there is no issue.
