I made my own DIY Wattson EasyFit Y Cable

After taking an original one appart, I tried to make my own DIY Easyfit Y Cable

I went to a supermarket on my way back from work, and found in the HiFi/Video/Computer cables section, this simple audio headphones coupler for 6 EUR

Back home, after diner, I took a pair of pliers and cut the cable in the middle, cut off 1cm of sheaf and split the wires

Connecting the red and white of the left and right (or opposite) together and the grounds together

Connecting the female sides ground cables together

Some solder is applied to the endings


and the wires are all soldered now


and the Y cable is almost ready for a first test


a little insulating tape, and it is plugged into the Wattson Transmitter: Like yesterday with the original Easyfit, it adds up the two CTs current - BTW the two CTs/sensors are inverted here -


Then plugging it into the Transmitter input 1, 2 or 3, it displayed 37.8kW (!!), and I realized something was wrong with my wiring ...



Measuring the jack contacts, I saw that the middle one should not be connected to anything,






So I removed the tape, unsoldered the wires - first time I used my solder sucker/pump, very handy - and identified the color of the middle contact: Red
I then simply cut off all the Red wires, they will not be used at ll, and re-soldered the White ones like before, re-taped,


and re-tested: Fine !
Here all 3 CTs/sensors current, 2 on Y cable, one alone, add up : 3 x 30W = 90W


Here: 2 CTs/sensors connected in Series via the Y cable: Their current readings add up

I then now have a low cost solution to be able to Double the Current Reading on a line, and this is exactly what I need to be able to make Wattson work for USA & Canada Split Phase Electric System.

See Energeno documentation and diagram on this smart Y cable called Easifit

DIY ESS - AC Charger terminals modification for Water Heater

Before moving all the ESS components to the metal cabinet, I decided to make a last modification to the charger side relay and AC terminals; Instead of having 6 relays for 6 chargers, I removed the 6th one AC wires and left the relay terminal free for my water heater command line (220V, 2A max) that activates the coil of a 220V 20A line that feed the water heater at night during off-peak hours. A signal sent by the utility closes a relay in my utility meter at night and opens it in the morning, and this is how the water heater runs only on low rate electricity. Closing the 6th relay on the same command line, I will be able to switch ON or OFF the water heater as a "6th charger" in a way, meaning, when all the chargers from 1 to 5 will have been switched ON already

If you get my kit, have no water heater - or a gas one, like many in the USA - , use the 6th relay for a charger - like I used too all this time - continuing the AC charger line up to relay 6, the behaviour of the 6th relay has not been changed at all, it is still the 6th charger from teh Arduino point of view !

Then I add to move two chargers on the same AC terminal/ relay twice, like you can see on the photo since I have 7 chargers

I also changed the program so that when the 5th charger comes ON, and the arduino sees that it uses too much power compared to the net power, instead of switching it back OFF, it switches the 1st charger OFF instead, making it more precise (so always install several chargers on the same line towards the end: 4th, 5th)