# help with brusa nlg513 as a booster in a nissan ev



## piotrsko (Dec 9, 2007)

Both chargers connect to the pack at start up?


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## glyndwr1998 (Apr 27, 2013)

hi all,

@piotrsko, yes both charger get the ac power at the same time.

an update,

the brusa charger i have here is a manufacture 2010 year make, the older black casing model. 

I have been playing with it all morning, and now got the chargewr running, but not the ideal solution.

My ideal solution was to run in booster mode. For some reason, the brusa did not like this.
So, i set the brusa to run in auto mode and programmed a very basic profile in auto mode, sent the new profile to the charger via rs232 and chargestar, and the charger started working ok immediately.

I tried again to get it to run on booster mode, it would not.

So, I have reset the charger to run in auto mode with a basic lithium charge profile, i have tested it, the charger runs until it gets to around 396vDC then swithes off, this equates to around 93% charge.
I tested this on 5 occaisions, and each time the charger switched off at the same point, so I,m ok at the moment with this setting.

If anyone has any idea why this brusa doesnt like boosted mode please advise.

Many thanks,

Anthony.


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## avi (May 27, 2017)

Hi All
I have a similar setup to the user above.
I am trying to charge a Nissan e-nv200 electric van (basically the same tech as the Nissan leaf).
Does anyone know what parameters is should program the Brusa nlg513 charger to? 
Thanks so much 
Avi


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## glyndwr1998 (Apr 27, 2013)

Hi Avi,

How far have you got with the project.
If you have already fitted the charger, and it is connected electrically, and ready to program,
You will need the chargestar software, a laptop running windows XP and a serial port.
When you ready, i`ll reconnect my laptop to the brusa and see what parameters i am using. It is a very basic profile, charging at 16A max current to a voltage of 396VDC which is about 93% state of charge of the env200 battery, at this point the brusa shuts down. 

Anthony.


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## Coulomb (Apr 22, 2009)

glyndwr1998 said:


> If anyone has any idea why this brusa doesnt like boosted mode please advise.


Sorry for the late reply. My guess would be the battery connections. If you have significant shared cable between where the chargers parallel and the battery, then the new charger will see a higher voltage than the battery actually is. It has to assume that the battery is nearly fully charged, hence the low current.

Ideally, the battery cables from the two chargers should connect right at the battery, with little to no shared cables. Of course, this may not be practical. A similar thing can happen if you have battery cables too thin, or if a fuse, connection, etc. has too much resistance.


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## glyndwr1998 (Apr 27, 2013)

Hi Coulomb,

Thank you for your contribution o the post.
I have been using the brusa in auto mode now since febuary charging twice a day without any issues at all.

I have not tried it on booster mode since, as I could not get it to operate in this setting.
If you could please explain further if you can on why you think the brusa will run ok in auto mode and deliver the full 16 amps, but not in booster mode when the battery connections and ac supply connectoins do not change at all.
As a mechanical engineer (not electrical) i could only think that there was something not right with the current sensor inside h brusa, although when connected to the laptop was showing the correct readings.

I was at a loss so I left it on auto mode with a very basic program loaded, and it is happy working in this setting, so i`m not too gutted about it, I would still like it to operate in booster but its not the end of the world if in this particular application in this vehicle it doesnt like it too much.

Anthony. 






Coulomb said:


> Sorry for the late reply. My guess would be the battery connections. If you have significant shared cable between where the chargers parallel and the battery, then the new charger will see a higher voltage than the battery actually is. It has to assume that the battery is nearly fully charged, hence the low current.
> 
> Ideally, the battery cables from the two chargers should connect right at the battery, with little to no shared cables. Of course, this may not be practical. A similar thing can happen if you have battery cables too thin, or if a fuse, connection, etc. has too much resistance.


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## Coulomb (Apr 22, 2009)

glyndwr1998 said:


> If you could please explain further if you can on why you think the brusa will run ok in auto mode and deliver the full 16 amps, but not in booster mode when the battery connections and ac supply connectoins do not change at all.


The attached shows two ways that you might be connecting the boost charger. In the upper case, supposing ridiculous voltage drops across the cables (10 V across any reasonable cable will fry it, but there could be a bad connection, or some weird galvanic action happening). With the original charger in place, the cables to the original charger are already 20 V higher (at maximum charging, as will happen at the start of a charge) than the battery voltage. If the boost charger attempts to charge at similar currents, and has similar voltage drops, it will see double the voltage boost at its terminals. Let's say the charger basically tapers off at 400 V; this would be the 200 W that you see. The original charger is used to the 380 V at its terminals, and charges at full current.

The one in twenty times when the boost charger is working, might be when it "gets in first", and the main charger runs at lower current.

When you press the switch on the J1772 connector, the main charger goes off, taking away the extra 20 V of voltage boost, so the boost charger (which still has a little energy in its capacitors) runs full current for a second or less. It all fits, except for the large voltage drops required for this story to make sense. This is all much more plausible when charging lower voltage batteries, like 12 V or even 48 V.

If you wire the boost charger directly to the battery, as in the lower part of the drawing, then the 20 V boost across the original charger leads don't affect the boost charger. It will be as if it's charging the battery all on its own, except that the battery magically seems to charger faster than expected (due to the presence of the original charger, of course).

They way I've drawn it, the second way will require more cable, but it depends on the position of the battery terminals and the two chargers. It might even take less cable this way.

Maybe the original charger is putting spikes on the battery voltage, which it filters for its own measurements, or it "knows when to look" to avoid the spikes. The boost charger is unable to do this, and measures a battery voltage that is much higher than reality, and hence it tapers the power down to 200 W. The fix is the same: wire directly to the battery. Cables have inductance as well as resistance. Although the bulk of the charge current (from either charger) is DC, the spikes are effectively quite high frequency (say 30 kHz, maybe 100 kHz or more). So if rearranging the wiring doesn't help, perhaps thicker cabling will. Obviously, you don't need to change the original charger's cabling, as it seems to work just fine.

If you are already cabling as per the lower part of the drawing, and are already using decently thick cable (say 12 AWG or thicker, lower AWGs like 10 AWG are thicker), then I don't know what else to suggest. Perhaps shielding.


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## glyndwr1998 (Apr 27, 2013)

Hi Coulonb,

When I instaled the brusa nlg513 as an addon, i read the manual taken from metricmind website, and on this was below. 

Booster Mode
The mains current of a Master NLG5 or any existing 
charger is wired through the Booster-NLG5. The 
Booster measures this current an adjusts its own 
current accordingly. 
As a result, the charging profile is still controlled by the 
original battery charger, but power is added by the 
Booster charger NLG5.

So, i took the ac supply cable to the original charger, split it, and routed the original AC supply through the addon brusa charger, so the brusa could monitor and read the AC current the original charger was taking, then give out the exact same current from the addon brusa in parallel. At least thats how it should work.
For some reason my brusa doesnt like operating in this mode.

I have used AWG10 cable. I will have to cheack the brusa charger DC cables where they are connected to the battery to ensure they are in good order and try again.
Thank you very much for your input to the thread.

Anthony.


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