Pre-charge and main contactor connections

[zippy500]

Is any one successfully running pre-charge and main contactor directly from the V3 board. I think this is the reason I fried my 1st board.

I have a second board now, I really want to be careful now, ( I dont want third time lucky).

So first time, I connected the a contactor to the pre charge out, the contactor which was just pulsing , although the current draw was within limit, so I connected the contactor via a small relay first. which worked ok for a couple of attempts. after that that's when the board shorted/overheated and does not work now. would the flyback voltage from the small mechanical relay cause this ?

So was that correct what I did ?

Is DCSW the output, for the main contactor ?

Is the process of pre/main a squence or timing only ?

Only other thought is make a Arduino setup to control the contactors independently from the V3 board and use the main contactor control signal to start the V3 board so there is no chance of trying to pull away on the pre charge and burn out the resistor.

I might do what Damian said on his video, and see if the small mobile repair shops can replace the smt parts on my first damaged board.

[Kevin Sharpe]

I have a second board now, I really want to be careful now, ( I dont want third time lucky).

Can you show us a drawing of your wiring?

What contactors are you using?

What firmware version are you using?

[zippy500]

V3 board was not old ( previous firmware, before current update) 2 months maybe

It was just on the bench, been completely dismantled now, want to start fresh now.

was using the EV200 Contactors 12/24v coil with economizer

[joromy]

Is DCSW the output, for the main contactor ?

Is the process of pre/main a squence or timing only ?

Yes the DCSW is for main contactor, but does not have any economizer PWM function!
It's using the well known and reliable ULN2003, just remember to connect to 12V ALL time.
If not there is nowhere for the back EMF to go.

The main contactor is not closed before the UDCSW voltage is reached.

[Kevin Sharpe]

It was just on the bench, been completely dismantled now, want to start fresh now.

Can you show us a drawing of your proposed wiring or a link to the reference you are using? AFAIK Johannes tests all boards before he ships them so you can assume the issue is with your implementation.

Edit: can you also confirm this is the kit you purchased?

https://openinverter.org/shop/index.php ... duct_id=57

[zippy500]

It was just on the bench, been completely dismantled now, want to start fresh now.

Can you show us a drawing of your proposed wiring or a link to the reference you are using? AFAIK Johannes tests all boards before he ships them so you can assume the issue is with your implementation.

Edit: can you also confirm this is the kit you purchased?

https://openinverter.org/shop/index.php ... duct_id=57

I know nothing there wrong Johannes boards, that is the problem is me , As Im just a hobbits I didn't know any Klingon I didn't understand what "open collector output" and "stardate ULN2003" was, Now I know means that it switches to ground,

I think I sent 12v down the DCSW output, which may have the problem.

Yes Im on my second set of this kit.

Thanks for everyones feed back

So should I use a small relay to control the EV200 contactor then ?

[Kevin Sharpe]

So should I use a small relay to control the EV200 contactor then ?

Please provide a drawing of your proposed wiring. It's really impossible to help you if you don't provide the basic information about your setup.

Please also supply a picture on the label on the contactor... the phrase "EV200" is not enough to determine which version of the contactor you are using.

If you prefer to do this without providing us with useful information then please consider using Johannes support services;

https://openinverter.org/shop/index.php ... duct_id=61

[zippy500]

of course, ill make a drawing of circuit for the pre-charge and main contactors and take a pic of my contactors

[zippy500]

so here is the contactors I will be using.
The pic has the economiser pcb, can I just remove the pcb and use it without, I assume they are just the coil wires.

Are the white wires volt free contacts when the contactor is energized ?


This is how I intend to connect up to the leaf board.

Can someone tell me if this correct ?

[joromy]

so here is the contactors I will be using.
The pic has the economiser pcb, can I just remove the pcb and use it without, I assume they are just the coil wires.
This is how I intend to connect up to the leaf board.
Can someone tell me if this correct ?

Wrong

This is correct, the openinverter does not have PWM economizer output, as far as I know.
What is controlling your Negative contactor, normally the BMS

[zippy500]

OK.Thanks

So there is no switch on the positive 12v to the contactors ?

So the economizer style contactors are suitable then for this setup.I might try and get one of the leaf contactor packages

[Kevin Sharpe]

So there is no switch on the positive 12v to the contactors ?

I don't know how the Negative Contactor is driven in the OI Mainboard but as a rule we don't use external BMS to control this because of the risk it will destroy the inverter power stage if it drops out under power (a common failure mode when the Tesla boards are wired up incorrectly). We really need Johannes or someone with detailed knowledge to tells us what they have in mind.

So the economizer style contactors are suitable then for this setup.I might try and get one of the leaf contactor packages

IIRC the Leaf Contactors don't have economizer circuits built in.

[Kevin Sharpe]

So there is no switch on the positive 12v to the contactors ?

I don't know how the Negative Contactor is driven in the OI Mainboard but as a rule we don't use external BMS to control this because of the risk it will destroy the inverter power stage if it drops out under power (a common failure mode when the Tesla boards are wired up incorrectly). We really need Johannes or someone with detailed knowledge to tells us what they have in mind.

A quick look at Main Board Rev 3 wiki (here) suggests that the negative contactor is not driven by the OI board. My guess is it's driven by the ignition switch but Johannes will need to confirm that.

[Kevin Sharpe]

so here is the contactors I will be using.
The pic has the economiser pcb, can I just remove the pcb and use it without, I assume they are just the coil wires.

I've attached the contactor datasheet. You can see the EV200HAANA01 part number tells you;

EV200 - 500A 900V contactor
H - Normally Open Contacts
A - 9-36V DV coil (requires external coil economizer)
A - 15.3 inch coil wire
N - no coil connector
A - bottom mount
01 - unknown

Are the white wires volt free contacts when the contactor is energized ?

yes

ENG_CS_EV200_R_TBD_KILOVAC_EV200_Ser_Contactors_0807.pdf

(250.07 KiB) Downloaded 100 times

[zippy500]

Ok Thanks, I thought to put the negative contactor on the first click on the ignition.

Think Arber said that you could damage the inverter,if you had to ignition off( for what ever reason) while still in motion

[Kevin Sharpe]

This is how I intend to connect up to the leaf board.

Can someone tell me if this correct ?

I don't think you can drive the main contactor direct from the OI board. The contactor datasheet tells us the inrush current is 3.8A and holding current 130mA whereas the OI board is rated at 300mA max (150mA max for precharge output). A lot depends on the economiser circuit and whether it has a soft start feature. We really need Johannes thoughts on this and ideally a wiring schematic

[Kevin Sharpe]

Think Arber said that you could damage the inverter,if you had to ignition off( for what ever reason) while still in motion

That's a valid comment... we really need Johannes to tell us what's he's thinking so that we don't need to guess

[zippy500]

OK thanks for your help

[mcgousha]

I went with the Arduino relay board option in order to stay within the current limits of the board. The ones designed for use with things like the Raspberry Pi/Arduino/STM32 draw very little current themselves (around 20mA) or so, but can handle 10A on whatever they are switching.

I'm guessing you meant something like this:
https://www.amazon.co.uk/ELEGOO-Optocou ... 06XK6HCQC/

I found them pretty easy to get working pulling 5v from that output on the OI board to power them and then using them to switch 12v to the contactors. I have the OI board DCSW and Precharge signals as the inputs on the relay board.

It may be overkill, but it's been pretty stable and it means I don't have to be too concerned about the specs on the contactors.

I currently have the negative contactor being triggered by the same 12v input that is powering the inverter itself.

[johu]

I see my thoughts were requested a number of times
Agreed you cannot drive any larger relay with the mainboard i.e. the ULN2003 directly - don't ask me how I know. A very effective solution is a P-channel mosfet whose gate is tied to source via 1k or so and is then pulled low by the respective precharge or dcsw output from the mainboard. Source is connected to 12V, drain to your relay, other end to GND permanently. The ULN2003 DIP version can directly switch a Leaf relay though.

I also agree that it is a bad idea to have the contactors controlled by anything else than the inverter. If you open the power path while in regen voltage will shoot up so fast that the slow overvoltage limit cannot catch it. Booom.

[celeron55]

I also agree that it is a bad idea to have the contactors controlled by anything else than the inverter. If you open the power path while in regen voltage will shoot up so fast that the slow overvoltage limit cannot catch it. Booom.

In my conversion my DIY BMS is controlling the main contactors. The VCU talks to the BMS and the inverter on CANbus. I'm fairly certain at some point in developing the system the BMS has opened the contactors while the VCU and inverter have been doing regen, but here's the catch: In my system the BMS has to report an "open contactor" and "no discharge permission" status for 3 seconds before it is actually allowed to open the contactor and the VCU will request zero current from the inverter when it sees those, or doesn't hear from the BMS for 1.5 sconds. Either that has saved my inverter (which is a Leaf gen2 unmodified) or the inverter has very fast overvoltage detection and has saved itself.

So while it's generally a bad idea it can definitely work just fine.

[joromy]

I also agree that it is a bad idea to have the contactors controlled by anything else than the inverter. If you open the power path while in regen voltage will shoot up so fast that the slow overvoltage limit cannot catch it. Booom.

But how can I control the NEG contactor from the openinverter?
And how could it open NEG contactor if the BMS detect an error?

I use the BMS for controlling NEG contactor now, maybe I could change it to only open NEG contactor if inverter is not in regen.
But that may be to late, to pick up (by CAN bus) and the inverter could be i regen again. I don't know how fast this needs to be,
What CAN data should I use to confirm that the inverter is in regen, with NEG DC current or POT2?

One possible solution is if the BMS could command the inverter in some way (CAN bus) to disable regen, and then open NEG contactor?

Sorry about all the question marks.... But I don't like Boom

[zippy500]

I'm Thinking of Putting the Neg contactor on the first click of the ignition key

second click to bring on main board and everything else,

As I am going to use the cars original gearbox, thinking of putting a switch on the original clutch pedal in series with the forward wire, to put the motor in neutral ( doesn't neutral position turn of the re-gen ?) and take the load of the gearbox.

[Kevin Sharpe]

So while it's generally a bad idea it can definitely work just fine.

Sorry about all the question marks.... But I don't like Boom

I know that several Tesla drive units have been destroyed by third party BMS opening one of the main contactors while the motor is under load. Presumably this would happen with other inverters as well. Given Damien, Johannes, and several other conversion shops do not allow the BMS control of the contactors I think you can safely follow their example

[Kevin Sharpe]

I'm Thinking of Putting the Neg contactor on the first click of the ignition key

I understand that is Damien's preferred approach.

As I am going to use the cars original gearbox, thinking of putting a switch on the original clutch pedal in series with the forward wire, to put the motor in neutral ( doesn't neutral position turn of the re-gen ?) and take the load of the gearbox.

Why add complexity when no one else does this?