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[Burton]

From watching EMW on youtube it doesn't seem they are catering to the 6k/7k crowd as it seems their main focus is cars.

That stated IDK if you could get 6kW out of a 240v 30A circuit since it needs to step down to 120v and there is bound to be loss.

Sadly the only thing that comes close is two EMW12kW when you consider cost >_<

Something like this but 6.6kw would be interesting as it is still air cooled but enclosed. http://www.currentways.com/ev-battery-chargers/air-cooled-chargers/3kw-bc-series-air-cooled-ev-battery-charger-96vdc-nominal/

[Burton]

Got some emails back from Valery, it seems they are working on a 7-8kW charger but I didn't ask when to expect it.

He said you can put two J1772 in parallel if they have the same phase to power the SuperCharger-12000

[benswing]

A portable 7kW charger would be great and would allow us to utilize the full capacity of Level 2 chargers. 

From what I read on another forum, it sounds like Level 2 chargers are often not in phase.  Wonder how hard it would be to make a portable rectifier that could adjust for that or leave the phase alone if it is already the same.

[Burton]

It has been a while and figured I would revisit this topic since I am having a slow week on my zero build.



The idea is pretty simple. Second J1772 from top should be labeled #2 not #1

Both 48 groups are in series with each other.
When the switch labeled Neg is set to A and the switch labeled Pos is set to A you have 2 RSP-2000-48v in series with one 12v. 5-6khw
When the switches are both changed to B then you have both RSP-2000-48 which are in series with their nearest neighbor on the diagram in parrallel with each other then in series with the 12v charger. 10-12kwh ?

This all assumes you are trimming the voltage up on the chargers. The range for the 48's is 42-56 and for the 12 is 10.5 ~ 14V
I forget what doc said about being able to trim both the current and the voltage up given you can go 125% higher in current on these chargers which would give you 52.5A for the 48's and 125A for the 12's (not that you would need it given the 2s2p 48's would max out at 105)

[Doctorbass]

The total power a RSP2000 can deliver when used on 240Vac is about 2500W when in current limiting state ( 125%) If you crank the voltage  up to 56V the max current will decrease a bit to follow the constant max power it can deliver. This is specified in a graph of their spec sheet.

Also you will need to add some Shottky diode in parallel to each output of RSP unit. This will protect against reverse current. It's IMPORTANT ! These diode must have higher current rating than the RSP unit it is connected to. finally I added one of these diode in serie  of the main output too to avoid reverse current even if the meanwell are set to inferior voltage as the battery is. The battery MUST NEVER push current to the charger!

This is a simple basic rule for many charger too and I just wanted to ensure everything is ok.

Also all paralleled meanwell must be connected with the current share function as stated in the spec sheet. This will ensure that they share 50% of the current each and there is none that is overcurrent compare to the next. it,s a simple pin that link together all parallel charger.

As well reading carefully the spec sheet is a must !

Good luck

Doc

[Burton]

I completely forgot about the diodes >_<
I will update the drawing later and make it look more technical with visio so it will be easier to read.

Do I need to worry about "charging curves" or real time limiting of these chargers? And if so do I just need to hook them up to the bike's BMS output (wherever that is)

I assume these would have to charge through the contractor on the bike given the auxiliary charging port is capped at 30 amps.

I really need to finish my total wire diagram for the bike.  I think I have 10 connections to go and since it is a slow week for the zero streamline project it would be good to finish it now.

Thanks for your help doc.

Oh and you said a 50% current share shouldn't it be a 33.33% current share given there would be at minimal 3 chargers running at one time to get the 117V required to charge the bike?  I also need to connect the stock chargers though I imagine I only need two in series to get the Sevcon to turn on and trip the contactor.

[protomech]

I completely forgot about the diodes >_<
I will update the drawing later and make it look more technical with visio so it will be easier to read.

Do I need to worry about "charging curves" or real time limiting of these chargers? And if so do I just need to hook them up to the bike's BMS output (wherever that is)

I am curious about that as well. Is it really as simple as a constant-current / constant-voltage switchover, and how well do these RSP power supplies follow that curve? I assume Zero charges the Farasis batteries at > 1C in order to make a 95% charge in 1 hour, but I'm curious if or when they slow the rate of charge. Farasis rates their cells at 0.5C maximum recommended charge rate .. but they may be able tolerate a significantly higher charge rate without issue.

Oh and you said a 50% current share shouldn't it be a 33.33% current share given there would be at minimal 3 chargers running at one time to get the 117V required to charge the bike?  I also need to connect the stock chargers though I imagine I only need two in series to get the Sevcon to turn on and trip the contactor.

No. Two RSP-48V are in series to make a stack, two stacks are in parallel.

[Burton]

No. Two RSP-48V are in series to make a stack, two stacks are in parallel.

I thought you needed 117 volts to get a full charge? two 56's would be 112 volts which is why I included the extra 12 volt power supply in series. This for a 2013 S of course.

[protomech]

Right, sorry.

All current passes through the RSP-2000 12V, up to 125A.

The RSP 12V is in series with the two RSP-48V stacks, which are in parallel.

The total current passing through the RSP-12V is split between the two RSP-2000 48V stacks, which should be configured to equally split the current (RSP-2000 48V maxes at around 42A + 25% = 52.5A, so two stacks in parallel could supply up to 105A total).

Therefore the entire assembly can supply up to 105A, or just over 1C charge rate for the ZF11.4 pack.