Hopefully this proves true and cutting the power to the ESC under load doesn’t cause any damage (including the Seaking ESC). What about the inducted current from the motor while it winds down (acting as a generator), doesn’t this energy normally get dissipated back into the battery? Or just stored in the capacitors?
What is the power consumption of the albright relay to hold the contacts closed?
Also would you mind posting a link to the lanyard you used? I’m trying to find a supply of a good one, other than Amazon.
The VESC and others you can program to limit the generated voltage.
It would swing between generating and driving dependent on the input.
As the rider is not on board anymore if the lanyard is pulled, the driving and controlling mass is not present any more, so the foil might glide, jump or just stop. The prop is rotated by the water randomly and can generate a voltage into the DC-Link circuit. There should be a zener diode. However,
What can the ESC do? If it still gets a valid signal for high throttle, it will sink the voltage out of the DC-Link within ms and go to Undervoltage, maybe reset, and so forth. It gets complex. Although i think, the motor is not able to produce Overvoltage in a passive B6 mosfet circuit. Maybe if you are towed or in big waves.
Better to use this switch under controlled conditions, with no motor driving, i agree. Better apply a braking command to the ESC, e.g. by cutting the signal. But also this comes maybe too late, if it takes 2 seconds.
So lets work on a safe remote control. A dial wheel, and a trigger switch, similar in function to my jigsaw. As long as you press the trigger, the motor will accelarate, in a moderate way to the given power or RPM or whatever given by the dial wheel which needs no attention by the rider. If you find you should drive faster, use your thumb to turn the cogged wheel a few teeth forward and a higher speed will be the result. If you want you can use this cogged wheel for dynamic maneuvers. The normal way to start the board would be a defined ramp up of power to a given end value, by just dialing in the wanted value and press the trigger. Whenever you release the trigger, the ESC goes to brake mode, but moderate.
I too like the triggers of cordless drilles. They are a better design like the gun trigger style I have seen here.
So you say the VESC will be alright? I am not sure if I should enable or disable breaking regeneration. (This is what you have been referring to right?)
Vesc will be definitely the way to go, as soon as max power/overheating issues would be solved, anyway, regenerative function can’t exist if a solenoid cut the battery connection!
Trigger drillbit style it’s a great idea, with a very reliable remote
It could work! Small relays protects the electronics. Basically, the first stage relay works as capacitors “precharge”? Let’s see how it goes. I wish to test the Vedder antispark soon, so we can compare these solutions.
I just tested the relay. I run it at 9.5V even though it is a 12V relay. I measured 1A of current. Unfortunatley, it reached about 90°C after about 10min. That is not acceptable. Any ideas what I could do? Would 12 or 15V help?
That was my idea last night, you could add a series resistor, but this would lower your losses only a bit as the resistor produces some heat then.
I would try to use one of those cheap 1€ buck converters / step-down converters from ebay and apply a lower voltage to the relays actuation coil. The relays coil is in static use like a resistor, it will draw current according to Ohm’s law. The the first buck converter I found is from china, but you should be able to find one from europe with reasonable shipping times.
But this is only an idea now, I don’t know how much you can reduce your temperature by this. But 25% * 12V = 3V and your coil has a resistance of 9,5V/1A=9,5Ohm. It should lower your losses to about 1W compared to 9,5W. You will have to test at which voltage your relay really drops off though.
Edit: You could get the same 3V across the relay and the same ~0,32A current with a series resistor of ~20Ohms but it will produce about 2W of heat.
You are using arduino to close it?
Why not use PWM signal?
Start with 100% Duty and after it is closed you can test with how low you can go, but I guess even 50% Duty should be enough…
Edit: only works if your relay closer relay is not mechanical.
Well, I can turn the UBEC down to 8V. And then make a relay divert the current through a buck converter at maybe 5V after the relay was closed. But with that I can only change the voltage. Will the coil not automatically draw more current at a lower voltage?
I could also take out the winding and double the number of loops with thinner windings.
