OpenEVSE - Open Source Charging Station

[chris1howell]

Hello Guys.

I have a question about the "Proximity" part:
In this tutorial I saw how the Pilot circuit was done, and i also found it in the Open EVSE Source Code. But J1772 also includes a proximity circuit.
(http://en.wikipedia.org/wiki/SAE_J1772#Signaling" onclick="window.open(this.href);return false. So there you have different resistances between PP & PE. Now i want to know, is this also included in
the Open EVSE Code? If so, please be so kind and show me this part please.

I hope that you can answer my question,
Kind Regards

Chris M.

Proximity is handled between the J1772 handle and the EV. The EVSE, charging station has no role in proximity.

Here is some referance information J1772 basics:
http://code.google.com/p/open-evse/wiki/J1772Basics

http://open-evse.googlecode.com/files/J1772.pdf

 

[ChrisM]

Hello.

Thanks Chris for the quick answer. Well I read a while ago, that the proximity tells the EVSE the available current of the EV (Link: http://de.wikipedia.org/wiki/SAE_J1772#Signalisierung" onclick="window.open(this.href);return false; - it is german: "Der Proximity-Schalter PP meldet den möglichen Ladestrom des Fahrzeugs an die Ladestation.") - you wrote, that proximity has nothing to do with the EVSE,so is this information wrong?

My next question:

This is the Type2-outlet:

For the electrical installation I have to connect the PP Pin to somewhere (?) or do I have to just leave it blank without any connection to somewhere?

This picture from the SAE J1772-2010 shows, that PP&PE are connected inside the cable, and only L,N,PE&CP are connected with the outlet from the EVSE - so why is there also a Pin on the outlet from the EVSE for the cable?

I already read all the basic & some detailed information about J1772, EVSEs & charging, but I never really understood the PP-part.

If you could answer those questions I would be very thankful,
Kind Regards

Christian M.





PS: I'm sorry if you think I'm asking stupid questions

 

[GlennD]

Yesterday I received my DIY openEVSE bare board and power supply. Today I finished and tested the unit. It is a very clean design. The only change I made was to bypass the processor with a cap between pins 7 and 8. I believe in bypass caps.

The unit tests OK with a test lash up. Chris it looks good and it is at a very good price.

My board will have different parts than the kit since I used parts on hand.

 

[TonyWilliams]

For the electrical installation I have to connect the PP Pin to somewhere (?) or do I have to just leave it blank without any connection to somewhere?

Normally, the proximity pin (PP) has no electrical connection to the EVSE electronics. It only needs to tell the car that the J1772 / Type plug is connected.

That is why the PP pin only goes to a switch and two resistors in the J1772 / Type 1 plug.

With 150 ohms, the signal to the car is "connected". To send a disconnect signal, press the switch on the J1772 plug and it will add 330 ohms in series (for 480 ohms total) to signal the car (and not the EVSE) that the plug is disconnected.

This will stop the flow of current and open the contractor in the car and then in the EVSE.

Edit: If you look again at the schematic, you see that Switch 3, and Resistors 6 and 7 go only to GROUND / EARTH in the EVSE. That is the proximity circuit in the J1772 / Type 1 plug.

 

[nsayer]

Hello.

Thanks Chris for the quick answer. Well I read a while ago, that the proximity tells the EVSE the available current of the EV (Link: http://de.wikipedia.org/wiki/SAE_J1772#Signalisierung" onclick="window.open(this.href);return false; - it is german: "Der Proximity-Schalter PP meldet den möglichen Ladestrom des Fahrzeugs an die Ladestation.") - you wrote, that proximity has nothing to do with the EVSE,so is this information wrong?

There is no communication to the EVSE of the vehicle's current requirements. The EVSE communicates to the car the amount of current available using the pilot signal, not proximity. If the EV doesn't like what it's being offered, its sole recourse is to not switch from state B to state C and complain to a human.

Some J1772 cord/plug combos don't even have a wire in the cable to take proximity back to the EVSE. In every EVSE I've seen so far, the proximity wire - if it's present - is left unconnected. The purpose of proximity is to communicate to the car that the plug is about to be pulled. The car reacts by immediately disabling the charger and transitioning to state B. That, in turn, instructs the EVSE to turn off the AC power.

 

[TonyWilliams]

In every EVSE I've seen so far, the proximity wire - if it's present - is left unconnected. The purpose of proximity is to communicate to the car that the plug is about to be pulled.

The Tesla UMC for Model S and X (and Model E?) uses the proximity wire for 3.2volts (NOTE: this is not part of the J1772 / Type 1 standard) to power the remote transmitter in the Tesla plug, which opens the charge port door on the car.

The bad news? It's blue... like the quasi standard for a pilot signal. Yes, I've wired them backwards twice already!!!

 

[ChrisM]

Hello.

Thanks for the answers. The product called "CM 230" from Siemens has this function:

"The CM230 recognises the max. allowed current from the cable using the proximity signal. Only when the max. current is as high or higher than the current that is defined in the Pilot circuit, the relais will be activated."

So does this CM230 just measure the resistance between PP-PE
(
total resistance PP-PE 1500 Ohm 680 Ohm 220 Ohm 100 Ohm
current capacity 13 A 20 A 32 A 63 A
wire cross section 1,5 mm² 2,5 mm² 6 mm² 16 mm²
Link: http://en.wikipedia.org/wiki/SAE_J1772#Signaling" onclick="window.open(this.href);return false;
)

and then activate the relais, or does it work different? Or is it even plausible to measure those resistances and then activate the current flow if the cable's max. current is higher or as high as the Pilot defined current?


Greetings Chris!

 

[TonyWilliams]

Hello.

Thanks for the answers. The product called "CM 230" from Siemens has this function:

"The CM230 recognises the max. allowed current from the cable using the proximity signal. Only when the max. current is as high or higher than the current that is defined in the Pilot circuit, the relais will be activated."

That is not correct. The max allowed current is from the EVSE generated 1kHz square wave sent via the PILOT signal, and the max amp value is sent with pulse width modulation.

The proximity does NOT do this. Sorry, but you're getting bad info.

 

[chris1howell]

Hello.

Thanks for the answers. The product called "CM 230" from Siemens has this function:

"The CM230 recognises the max. allowed current from the cable using the proximity signal. Only when the max. current is as high or higher than the current that is defined in the Pilot circuit, the relais will be activated."

So does this CM230 just measure the resistance between PP-PE
(
total resistance PP-PE 1500 Ohm 680 Ohm 220 Ohm 100 Ohm
current capacity 13 A 20 A 32 A 63 A
wire cross section 1,5 mm² 2,5 mm² 6 mm² 16 mm²
Link: http://en.wikipedia.org/wiki/SAE_J1772#Signaling" onclick="window.open(this.href);return false;
)

and then activate the relais, or does it work different? Or is it even plausible to measure those resistances and then activate the current flow if the cable's max. current is higher or as high as the Pilot defined current?


Greetings Chris!

I think the confusion comes from a very poor wikipedia article that mixes a old version of J1772:2001 and standards from IEC_62196.

OpenEVSE and modern EVs are all based on J1772:2010.

The Wikipedia article defines PP As Proximity Pin (not Pilot) and CP as Control Pilot.

Here is a J1772 Basics document from the OpenEVSE site: http://code.google.com/p/open-evse/wiki/J1772Basics

 

[davewill]

... The purpose of proximity is to communicate to the car that the plug is about to be pulled. The car reacts by immediately disabling the charger and transitioning to state B. That, in turn, instructs the EVSE to turn off the AC power.

Not so much. You can press and hold the button and the LEAF does NOT have EVSE turn off AC power. It just stops drawing current. It requires actually removing the plug from the car to get the EVSE to turn off AC.

 

[ChrisM]

Hello.

Thanks for the answers. The product called "CM 230" from Siemens has this function:

"The CM230 recognises the max. allowed current from the cable using the proximity signal. Only when the max. current is as high or higher than the current that is defined in the Pilot circuit, the relais will be activated."

So does this CM230 just measure the resistance between PP-PE
(
total resistance PP-PE 1500 Ohm 680 Ohm 220 Ohm 100 Ohm
current capacity 13 A 20 A 32 A 63 A
wire cross section 1,5 mm² 2,5 mm² 6 mm² 16 mm²
Link: http://en.wikipedia.org/wiki/SAE_J1772#Signaling" onclick="window.open(this.href);return false;
)

and then activate the relais, or does it work different? Or is it even plausible to measure those resistances and then activate the current flow if the cable's max. current is higher or as high as the Pilot defined current?


Greetings Chris!

I think the confusion comes from a very poor wikipedia article that mixes a old version of J1772:2001 and standards from IEC_62196.

OpenEVSE and modern EVs are all based on J1772:2010.

The Wikipedia article defines PP As Proximity Pin (not Pilot) and CP as Control Pilot.

Here is a J1772 Basics document from the OpenEVSE site: http://code.google.com/p/open-evse/wiki/J1772Basics

Hi, please be so kind an read on page 19 - "Proximity". This is an official document from Siemens.

http://www.google.at/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CDUQFjAB&url=http%3A%2F%2Fsupport.automation.siemens.com%2FWW%2Fllisapi.dll%2Fcsfetch%2F48460217%2Foperating_instructions_ECC_CM-230_en-US.pdf%3Ffunc%3Dcslib.csFetch%26nodeid%3D49949215%26forcedownload%3Dtrue&ei=GT8WUs3tHqbi4QST7IGwDg&usg=AFQjCNEvNl0IEG5Zy8hqxxWgAXqGhKWcgA&sig2=NEsRwO5RpwoaEWJCPG84Hw&bvm=bv.51156542,d.bGE&cad=rja" onclick="window.open(this.href);return false;

Thanks in advance, Greetings Chris

 

[QueenBee]

Hello.

Thanks for the answers. The product called "CM 230" from Siemens has this function:

"The CM230 recognises the max. allowed current from the cable using the proximity signal. Only when the max. current is as high or higher than the current that is defined in the Pilot circuit, the relais will be activated."

So does this CM230 just measure the resistance between PP-PE
(
total resistance PP-PE 1500 Ohm 680 Ohm 220 Ohm 100 Ohm
current capacity 13 A 20 A 32 A 63 A
wire cross section 1,5 mm² 2,5 mm² 6 mm² 16 mm²
Link: http://en.wikipedia.org/wiki/SAE_J1772#Signaling" onclick="window.open(this.href);return false;
)

and then activate the relais, or does it work different? Or is it even plausible to measure those resistances and then activate the current flow if the cable's max. current is higher or as high as the Pilot defined current?


Greetings Chris!

I think the confusion comes from a very poor wikipedia article that mixes a old version of J1772:2001 and standards from IEC_62196.

OpenEVSE and modern EVs are all based on J1772:2010.

The Wikipedia article defines PP As Proximity Pin (not Pilot) and CP as Control Pilot.

Here is a J1772 Basics document from the OpenEVSE site: http://code.google.com/p/open-evse/wiki/J1772Basics

Hi, please be so kind an read on page 19 - "Proximity". This is an official document from Siemens.

http://www.google.at/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CDUQFjAB&url=http%3A%2F%2Fsupport.automation.siemens.com%2FWW%2Fllisapi.dll%2Fcsfetch%2F48460217%2Foperating_instructions_ECC_CM-230_en-US.pdf%3Ffunc%3Dcslib.csFetch%26nodeid%3D49949215%26forcedownload%3Dtrue&ei=GT8WUs3tHqbi4QST7IGwDg&usg=AFQjCNEvNl0IEG5Zy8hqxxWgAXqGhKWcgA&sig2=NEsRwO5RpwoaEWJCPG84Hw&bvm=bv.51156542,d.bGE&cad=rja" onclick="window.open(this.href);return false;

Is this how a EVSE with Mennekes could determine that the user provided the proper cord?

 

[ChrisM]

Is this how a EVSE with Mennekes could determine that the user provided the proper cord?

Well, as described in this document from Siemens, the EVSE-(Controller) checks if a proper cord is used or not, and when the right one is used, the EVSE is ready for charging.

 

[chris1howell]

... The purpose of proximity is to communicate to the car that the plug is about to be pulled. The car reacts by immediately disabling the charger and transitioning to state B. That, in turn, instructs the EVSE to turn off the AC power.

Not so much. You can press and hold the button and the LEAF does NOT have EVSE turn off AC power. It just stops drawing current. It requires actually removing the plug from the car to get the EVSE to turn off AC.

Davewill is correct. When the proximity detects a button press the vehicle stays in State C but the EV must stop pulling current within 100ms. The relays will stay closes and will disconnect within 5 seconds of losing the pilot when the cable is pulled. This provides a soft-start and soft-stop to protect the relay contacts and the J1772 outlet/inlet for arching.

 

[chris1howell]

Is this how a EVSE with Mennekes could determine that the user provided the proper cord?

Well, as described in this document from Siemens, the EVSE-(Controller) checks if a proper cord is used or not, and when the right one is used, the EVSE is ready for charging.

The Seimens document confirms the device is using the IEC 61851 method instead of the J1772:2010 for current selection.

OpenEVSE could be modified to support IEC 61851 proximity but it currently does not. Most International builders use the J1772:2010 pilot to communicate current to the vehicle. The user must ensure they are using the correct Mennekes cable for the current setting.

 

[Roberto33]

Hello chris1howell

As change default Service Level 2 in the firmware?

My installation is 230v single phase (Spain), but OpenEVSE is identified as Level 1

Thanks

 

[chris1howell]

Hello chris1howell

As change default Service Level 2 in the firmware?

My installation is 230v single phase (Spain), but OpenEVSE is identified as Level 1

Thanks

Using a Push button and LCD.
Push and hold to enter Menu
Short push to select each option
Push and hold to modify "Service Level"
Short push to select each option

Change Auto to L2

 

[nsayer]

When the proximity detects a button press the vehicle stays in State C but the EV must stop pulling current within 100ms. The relays will stay closes and will disconnect within 5 seconds of losing the pilot when the cable is pulled. This provides a soft-start and soft-stop to protect the relay contacts and the J1772 outlet/inlet for arching.

Huh. When I press the button and do nothing else, my Fit EV waits a tic (I want to say it's a hundred msec or two) and then transitions to state B. I rather suspect that the brief delay is, as you said, an arc preventative delay. But in the end, I do see it go to state B before I pull the handle out.

 

[davewill]

Huh. When I press the button and do nothing else, my Fit EV waits a tic (I want to say it's a hundred msec or two) and then transitions to state B. I rather suspect that the brief delay is, as you said, an arc preventative delay. But in the end, I do see it go to state B before I pull the handle out.

I had wondered about that. I knew the LEAF would stay connected no matter how long you held the button, but I've been unsure whether that was the "correct" behavior. Possibly, both behaviors are OK. Suffice it to say, an EVSE should be ready to handle both.

One downside to the Fit's behavior: If someone plays with the button while you're connected to a public EVSE, you could end up not charging, needed to reauthorize to get started again (and possibly being charged extra for partial hours, etc...).

 

[chris1howell]

Huh. When I press the button and do nothing else, my Fit EV waits a tic (I want to say it's a hundred msec or two) and then transitions to state B. I rather suspect that the brief delay is, as you said, an arc preventative delay. But in the end, I do see it go to state B before I pull the handle out.

I had wondered about that. I knew the LEAF would stay connected no matter how long you held the button, but I've been unsure whether that was the "correct" behavior. Possibly, both behaviors are OK. Suffice it to say, an EVSE should be ready to handle both.

One downside to the Fit's behavior: If someone plays with the button while you're connected to a public EVSE, you could end up not charging, needed to reauthorize to get started again (and possibly being charged extra for partial hours, etc...).

As far as J1772 is concerned the LEAFs behavior is a more literal implementation of J1772, but the Fit is not doing anything wrong either. The Fit likely is still removing current within 100ms but it is going through an extra step to move to State B which would cause the relay to Open. Going from State C to state B for a proxitimy event is not required by J1772 but cutting current within 100ms is.

EVSEs can handle either method but my opinion is the LEAFs behavior is better for authorization, timer overrides and reducing cycles of the relay.