Just a little update for anyone interested in my build:
hatch will be costum made from carbon fibre, with that cam hatch latches (i would apritiate if anyone could tell me which cam latches are waterproof from expirience)
battery box will be made out of carbon using 3d printed calup (prictures are rendered by f360)
for the contactor I got monostable reley (control using pwm) from electric car industry (it is like 70x70x20mm) and I am in process of making arduino turn on the reley
Nice battery box!
Arduino. - This is what my dad made to turn on the main relais.
It does also monitor pre-charging and temperature of the VESC (cooling pump on/off)
Basically when the Arduino is turned on by using a magnet on the reed switch (not shown in the picture), the Arduino will turn on relay 1, for pre-charging the VESC.
When pre-charge is done (monitored by the Arduino), it will turn on the 2nd relais what will power the big main relais.
The Arduino is also monitoring the temperature of the VESC. When the temperature gets to high (I think that it is set to 30c) it will turn relais 3 on and start the pump.
The little screen is only to show some debug info.
Communications from VESC <> Arduino is by TX/RX from the VESC’s comm port.
He is now working on a FET version to replace the 3 relais, and instead of using the comm port he is trying to use the CAN port.
Woaw, great job with those arduino and releys!
Well my idea is to have just normal click switch (waterproof) to have it in my electric box to turn the main reley on. I am not planning to use pump, just a water pressure since my mast clamp for rl boards is designed in that way to put as much water as can thru mast. My reley is monostable and it is turned on by sending unique 12V pwm (1 impulse high, other low). It is designed to work up to 60V 200A.
On monday my VX3 flipsky chould arrive and that is the remote I will use!
We 1st used an expensive waterproof switch, but unfortunately this one did still leak water (only a little bit)!.
We also tested without a pump and only cooling by water pressure. This does work, but only als long as you are going forward. When you stop, the temperature will shoot up for some time!
With or without pump, the aluminium case above the mast plate has a point.
@kian - great job.
@lukomo - this is a problem I have been trying to solve as well.
The issue;
@kian’s solution looks good. I would love to learn more.
I have tried to solve this with the Maytech anti-spark switch, but the cannot handle the current. See this post, I have had three fail;
Maytech will not even talk to me now. I think the main issue is that Mossfet circuits simply cannot handle the big back EMF and high voltage spike that occurs when the magnetic field in the motor collapses when power is cut.
I am also looking at the Arduino option where the Arduino would also throttle down the motor briefly before disconnecting power. So the functionality would be;
Functionality;
There may also be the option to use the arm/disarm function of some VESCs.
I plan to use this arduino based processor which is safety rated and runs three cores in parallel to increase safety;
I have used them previously and they are very fast.
I will use one core to control relays. One core to control comms and one core to monitor the other two cores.
I would love to know everyone’s thoughts.
I am just starting a new build. It will have twin MHZ 58s with scorpion motors(on their way) and will use 2 x MakerX new 300A VESCs.
The other reason I am running the remote through the Shiledbuddy is that I need to control two VESCs from the one remote. Essetially, I will have two batteries, two VEScs, two motors and two jets, so there is no single point of failure other than the remote and the Shield buddy (which is safety rated).
I will also have a waterproof hall effect single axis throttle lever built into teh board so that you can over ride the remote.
Maybe you alredy know but just in case you didnt, you can connect the 2 vesc together via CANbus and set one as address 0 and the address 1, make 0 the master and connect the remote to the master, it can fwd the signal to the other vesc via the coms so you can use 1 remote to control multiple vescs.
Thank you! I did not know this.
It’s my dad who made this so I will need to ask him. I will let you know when I know more.
I’m only the tester of his creations 
You’re lucky to have a dad with that skillset!
Does anyone have any expirience with this kind of buttons. They should be waterproof, but I am not sure if its true…
I was looking at something like this:
This push button is rated IP 65, so not 100% waterproof!
We tested a push button with a rating of IP 67, and it was still leaking a little bit.
Link to the button we used (sorry in Dutch) %product-title% kopen ? Conrad Electronic
They are not waterproof, especially when you push them in the wet. If it is for a remote, either use foil keys or piezo. Disadvantage is both are not latching, so you need some logic behind them to recognize a pulse and do somerhing, i.e. switch on the remote.
I will use it to turn on the monostable reley (that means button will be connected to the arduino)
I use similar buttons in my build. But I covered them with rubber from the expander. They have been working for three years! No problems. In our other assembly, we use it without rubber, the season has worked, so far there are no problems!
Why do you want to use an Arduino to just turn on the monostable relay? Or. Will you do like us, and monitor more data from the vesc?
Great, can oyu tell me what latches did you use, and how are they performing?
BR
The main reason for using arduino is to send unique pwm signal to the monostable reley (you turn it on by sending pwm). I might use that arduino to save some basic data to SD card.
