100A Battery Switch Isolator To Hot to Touch as The 150A Meter.

[gordon_s1942]

For the high current your using I am not overly thrilled by the construction of that very flash looking dual Knife switch as it looks as though the tangs where the blades sit is either plain or pop riveted to the plate on the base.
If what looks like rivets are in fact dimples cause by some sort of electro Spot welding technique then ignore this and any further comments.

If it is riveted, I would NOT remove them if everything is made of Copper and/or Brass but see if there was a way of braising/welding the tangs to form the best possible electric bond available.

Years ago I used a 'phoscopper rod (and Oxy-Acetelene) to braise up a split in a 60 gallon copper tank and it was like a 'Hard' Solder', a step above 'Silver Solder'.

[GT250]

Update:

I flicked open the knife on the 60A and fuse switch on the 40A controllers at about 5:00am and left them open until about 11:00am when I hope to get a 100A input.

At about 7:00am, I decided to vacuum (1500W), for about 10minutes, Microwave (1000W), for about 5mins on and off. Put the kettle on (2000W), three times (2mins each), to soak up any surface voltage and also put a drain on the batts over a space of about 50minutes. Then I left the batts running the three fridges and the other bits and bobs in the house as they normally do (24/7) until 11:00am.

The voltage went down to about 23.1v.
Then I closed the switches and watched the Amp inputs with the Fluke connected.
The amps went quickly to 100.

NB: The 200A meter is now connected by using the long 2mtr data cable, with the Fluke meter next to it's hall effect ringy thing at the batt terminal.
The 200A meter registered 103A when the Fluke was showing 105A.

The 100A meter (inaccurate one), I have connected to the input of the PL60, before the knife and it was showing a -2A difference of the PL60.

So to cap it off: The 200A meter is more accurate, as it showed all the Amps fairly ok up to 100A. However, the 100A meter as the above picture shows at 80A+, there is a 12A difference - way out...!

I have asked to return it. Have to go by UPS, the cost to NJ (USA), is $42... So I won't be doing that.... It's accurate enough at around the 50A area, so it can look at after the input to the PL60.

Gordon: I know It looks cheap. But remember that I bought those Rotary 120A Switches in AUS, and they were too hot to touch! After today, I had a full 60A current going into the PL60 for about 3 hours. However, previously I had said that they were 'luke warm', but today they were warmer than that, slightly hot to touch, but ok. Then again, it had been on FULL 60A for 4hours...

As for the rivets, I understand what you are saying. I've looked at the amount of metal from point A-B. As It's metal I have thought about soldering 'veins' to the connecting places.
It's on my 'to do list' to keep my eye those connections and I truly appreciate your advice to watch for those riveted contact points.


I hope that my trials and tribulations help anyone.
Cheers,
GT250.

[gordon_s1942]

This wont apply to you but I was told that where 'spot welds' are used on cars, while mechanically strong, are NOT good conductors of electricity.
This came up from a Radio Amateur who was suffering 'noise' on the amateur bands.
By a process of elimination, he found that although the body panels were spot welded, it still allowed almost imperceptible movement between the joined panels and this caused the noise.
This why I would consider taking one lead directly to the blade itself which would eliminate that connection on the base and the pivot bolt.

[bob_m_54]

This wont apply to you but I was told that where 'spot welds' are used on cars, while mechanically strong, are NOT good conductors of electricity.
This came up from a Radio Amateur who was suffering 'noise' on the amateur bands.
By a process of elimination, he found that although the body panels were spot welded, it still allowed almost imperceptible movement between the joined panels and this caused the noise.
This why I would consider taking one lead directly to the blade itself which would eliminate that connection on the base and the pivot bolt.

Spot welds conduct electricity as well as any other part of the body metal. How did he eliminate the problem he was having?

As for the rivets, if they eventually get corrosion between the metal and the rivet, this would be a cause of poor conduction. This is unlikely if the rivets are of the same metal as the plates, and they have been riveted correctly to exclude any gaps between the rivet and the holes (essentially sealed). However, the pieces that are riveted together will still be in contact, and again, if the riveting has been done correctly, so as not to distort the metal plates, they would also make a pretty good conduction path.