EV car conversion hardware

[SciroccoEV]

From a year 2000 edition of "Electrifying Times" magazine;

[ZooKeeper]

post deleted

[arber333]

HM... Some posts reminded me of a thing i made for testing basically any Johannes board, be it Rev1, 2 or the newest edition.

I took a block of good straight wood. I screwed on a wide alu angle so i had somewhere to put my switches. Underneath the angle i sorted all the wires.
DC contactor, precharge relay, warning LEDs and large resistor i fixed to wooden support.

I made a harness from 20 wire signal cable and i used numbered wires for every line.
I used standard 16 pin crimped sealed connector from aliexpress
This way whatever inverter i use i will have the same setup and interchangeable connectors on all.

I can thus test all inputs as well as most of the outputs with this. It lets me connect directly to inverter and 400Vdc battery, or 60Vdc battery if i choose it.
I think it was well worth investing some switches, DC contactor, relay, Prius pedal some wire and large 150R resistor.

[RetroZero]

Looks good and helps with testing.

[johu]

I use the pressure/vacuum sensor with part number 036906051G to control the vacuum pump in both my conversions.

Its supply voltage is 5V and it outputs an analog voltage proportional to the pressure, i.e. the more vacuum, the lower the voltage. The voltage can either be used with a voltage divider and a heavy low pass filter (1 Hz) to control an NPN transistor (that controls a relay) or with an ADC. I have tried both and it works well. It is important to have some hysteresis otherwise the pump tends to switch on and off around your desired vacuum.

The given part number is just for the sensor, try to get the whole assembly as depicted. It also contains a kickback valve.
The part number for the matching connector should be 1J0973724 is 1J0973704.

[Bassmobile]

At $290 is somewhat expensive though.

Organise a group buy direct from ISA in Germany... at 12 pieces the pricing is *much* better than you're being quoted in distribution

Definitely interested in a helping to organize a group buy of these ISABELLENHÜTTE 1000A CAN Shunts. Will commit to purchase four units personally. Anyone else like to get in on a group purchase from ISA in Germany as Kevin Sharpe suggested? Please chime in or PM me!

[jnsaff]

See here viewtopic.php?f=12&t=641 happy to put in another order and ship them out. Otherwise they are quite accessible and you can definitely get a good quote from them direct.

[mdrobnak]

Re: ISABELLENHÜTTE 1000A CAN Shunts could someone tell me what they are being used for? Are they required to get the DC current info in the web interface for the VCUs? It's just unclear why I'd want to buy it.

Also,have we put the info in this thread on the Wiki? If not, I'll try and get some of it in there this week (I've taken off of work to work on car stuff mostly)

-Matt

[johu]

Yes a wiki page would be awesome. Just name it the same as this thread.

[Kevin Sharpe]

Re: ISABELLENHÜTTE 1000A CAN Shunts could someone tell me what they are being used for? Are they required to get the DC current info in the web interface for the VCUs? It's just unclear why I'd want to buy it.

It measures pack voltage at three locations, current, has a coulomb counter, is a BMS, and has lots more functions (see datasheet). It's a standard feature of Damien's conversions today and going forward. If you don't want to reinvent the wheel then invest the 160 euros

We'll document many of the features in the wiki;

https://openinverter.org/wiki/Isabellen ... te_Heusler

[mdrobnak]

Re: ISABELLENHÜTTE 1000A CAN Shunts could someone tell me what they are being used for? Are they required to get the DC current info in the web interface for the VCUs? It's just unclear why I'd want to buy it.

It measures pack voltage at three locations, current, has a coulomb counter, is a BMS, and has lots more functions (see datasheet). It's a standard feature of Damien's conversions today and going forward. If you don't want to reinvent the wheel then invest the 160 euros

We'll document many of the features in the wiki;

https://openinverter.org/wiki/Isabellen ... te_Heusler

So the part that confuses me is - OK great, pack voltage measurement (in multiple places)..but no balancing. So it doesn't really replace a BMS in that respect. Coulomb counter / kWh used definitely useful. I guess multiple datapoints is not necessarily bad, so maybe I'll buy it anyway.

[johu]

Could you please move this discussion to a bespoke thread, thanks

[arber333]

Well you need your voltage and amp counter in your ev. But from them you get your power and energy left in battery.

If I didn't have one EVdisplay left to use I would definitely buy one of those sensors.

[Kevin Sharpe]

So the part that confuses me is - OK great, pack voltage measurement (in multiple places)..but no balancing. So it doesn't really replace a BMS in that respect. Coulomb counter / kWh used definitely useful. I guess multiple datapoints is not necessarily bad, so maybe I'll buy it anyway.

It's very simple, you follow Damien's lead or choose your own path

[konstantin8818]

Are this contactor assemblys from Toyota HV battery of any good use?
Two contactors at both positive and negative lines, precharge relay with resistor and as far as I can say - with built in current sensor.

Why I'm asking? There is a guy, who sell toyota HV cells, and those assemblys are "leftovers no one needs" and he sell them for ~30 euro, and as he says, he have got "many of those".
I've bought one and tested - it works.

[Kevin Sharpe]

I've bought one and tested - it works.

How long did you run the contactors for? You need to run them for an hour or so at ~14V and measure the temperature rise to ensure they will work long term.

Great find even if they need external economizers

[konstantin8818]

How long did you run the contactors for? You need to run them for an hour or so at ~14V and measure the temperature rise to ensure they will work long term.

Great find even if they need external economizers

Will do. Just need to wait until summer refreshes in it's memory it is time to show up My garage is opened to every winds. I've just detached economizers from kilovac contactors, because they were jumping like crazy. So I need to attache them back?

[Kevin Sharpe]

So I need to attache them back?

If you run a contactor that requires an economizer without one then you'll burn out the coil.

[xp677]

You can also just send a PWM signal to them (this is essentially what the economiser does). Start at 100% and then drop it to whatever keeps it closed.

I use this code to achieve this:

Code: Select all

#define CONT_MAXPWM 2550 //start pwm value
#define CONT_MINPWM 1280 //end pwm value
#define CONT_PWMRATE 1 //rate of change

//setup
int c_pos_pwm = CONT_MAXPWM;

//contactor function, called from loop
    if (contactor[C_POS])
    {
      if (c_pos_pwm > CONT_MINPWM) c_pos_pwm -= CONT_PWMRATE;
      analogWrite(CONT_POS, (int)c_pos_pwm / 10);
    }
    else
    {
      analogWrite(CONT_POS, 0);
      c_pos_pwm = CONT_MAXPWM;
    }
    
    //same again for negative contactor, etc

Of course you need a suitable circuit to drive the coil. Best to keep the economiser. I run Kilovac contactors (with economiser), with a 10A relay to trigger them. The code above is used as an economiser for the 10A relay.

[konstantin8818]

You can also just send a PWM signal to them (this is essentially what the economiser does). Start at 100% and then drop it to whatever keeps it closed.

Of course you need a suitable circuit to drive the coil. Best to keep the economiser. I run Kilovac contactors (with economiser), with a 10A relay to trigger them. The code above is used as an economiser for the 10A relay.

I'm barely understand this programming thing. Also contactor in this board activates true BTS117. Are they capable of handling PWM signal? Won't they overheat? I'll better solder those economisers back.

[Kevin Sharpe]

You can also just send a PWM signal to them (this is essentially what the economiser does). Start at 100% and then drop it to whatever keeps it closed.

Of course you need a suitable circuit to drive the coil. Best to keep the economiser. I run Kilovac contactors (with economiser), with a 10A relay to trigger them. The code above is used as an economiser for the 10A relay.

I'm barely understand this programming thing. Also contactor in this board activates true BTS117. Are they capable of handling PWM signal? Won't they overheat? I'll better solder those economisers back.

Most contactors require economizer functionality to minimise power consumption in the coil. This can be built into the contactor, an external circuit, or via software/hardware in the controller.

AFAIK none of the Open Inverter boards support software/hardware economizer functionality directly (they're just simple switched outputs) and therefore you need to implement this yourself with an external board or use a contactor that has the functionality built in.

[konstantin8818]

AFAIK none of the Open Inverter boards support software/hardware economizer functionality directly (they're just simple switched outputs) and therefore you need to implement this yourself with an external board or use a contactor that has the functionality built in.

I used to program Curtis inverter and that guy wasn't happy about economiser. There are parameters as pull in and hold voltages, it also detects any failure within any circuit. Really bullet-proof design as it turns out=)

[Kevin Sharpe]

AFAIK none of the Open Inverter boards support software/hardware economizer functionality directly (they're just simple switched outputs) and therefore you need to implement this yourself with an external board or use a contactor that has the functionality built in.

I used to program Curtis inverter and that guy wasn't happy about economiser. There are parameters as pull in and hold voltages, it also detects any failure within any circuit. Really bullet-proof design as it turns out=)

The great thing about open source is that you can change anything you want. Indeed, Damien and Johannes are using different contactor driver chips iirc. My approach is to use contactors with built in economizers and that's something we recommend on our courses

[xp677]

BTS117 contains a load of extra components for the various protection measures, not sure how it would handle PWM, I imagine it would depend on your switching frequency.

The economisers which come with the Kilovac contactors are best suited for the job.

I was advised (probably in another thread on this forum) not to use transistor-based switching for the power input to the economisers on these contactors. Which is why I used a small relay.

The PWM code above is just there to reduce the power consumption of that relay. It reduced the relays coil power by about 1W, which is a good result for just a few lines of code.

[Kevin Sharpe]

The PWM code above is just there to reduce the power consumption of that relay. It reduced the relays coil power by about 1W, which is a good result for just a few lines of code.

Just to be clear, was that code tested on non modified open inverter hardware and if so which boards?