Yes, it does. If you charge at say 2.5A, 8A will be going down the leads from your 12v battery. You need pretty thick wire if you run any distance because there will be a voltage drop down the wire. Your charger won't work if the voltage goes too low.

 

You can calculate the drop using this calculator:

 

http://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=8.286&voltage=12&phase=dc&noofconductor=1&distance=20&distanceunit=feet&amperes=8&x=57&y=9

 

It shows that you'll lose 0.81v through 20 feet of 14g wire or 0.51v with 12g.

Yes, the manual does look a bit daunting at first - but to be honest you won't need to use much of it at all. The charger can do some pretty impressive things regarding balancing the individual cell voltages during various stages of charging, and that is what the multistranded lead is for. However you won't be using that as you are using a commercially built battery pack with its own BMS and you won't have access to the individual cell voltages unless you take it apart. You will just be using the positive and negative charger outputs.

 

It doesn't matter about lead length, as long as you don't go silly. You have two options:

1. Have the charger outside the van at the end of the long lead. You will be drawing just over 3 times the charging current from your van battery as d8veh says, so there will be some voltage drop. However the charger is happy at anything down to 10 volts so it's got to drop quite a long way before troubling the charger (although of course your van battery will be dropping as well). However the better method is the one I think you were meaning, which is
   
2. Have the charger in the van with long charging leads going outside to the bike. Voltage drop is much smaller as you're only pumping say 2.5 amps through the wires, and also as the charger reaches towards completion it starts throttling back the current anyway, so the voltage drop reduces. For a normal charge the charge will finally stop when it reaches down to 1/10 of the set current, i.e. 0.25A if you charge at 2.5A. For the 20 foot wire mentioned above there will only be a voltage drop of 0.025V at that final current - not worth worrying about.
   

If you have any questions about the manual don't hesitate to ask. The most important settings are how to turn off the infernal beep when you press any key, and to prevent the buzzer from going non-stop when it finishes the charge!

 

Michael

Yes, the manual does look a bit daunting at first - but to be honest you won't need to use much of it at all. The charger can do some pretty impressive things regarding balancing the individual cell voltages during various stages of charging, and that is what the multistranded lead is for. However you won't be using that as you are using a commercially built battery pack with its own BMS and you won't have access to the individual cell voltages unless you take it apart. You will just be using the positive and negative charger outputs.

 

It doesn't matter about lead length, as long as you don't go silly. You have two options:

1. Have the charger outside the van at the end of the long lead. You will be drawing just over 3 times the charging current from your van battery as d8veh says, so there will be some voltage drop. However the charger is happy at anything down to 10 volts so it's got to drop quite a long way before troubling the charger (although of course your van battery will be dropping as well). However the better method is the one I think you were meaning, which is
   
2. Have the charger in the van with long charging leads going outside to the bike. Voltage drop is much smaller as you're only pumping say 2.5 amps through the wires, and also as the charger reaches towards completion it starts throttling back the current anyway, so the voltage drop reduces. For a normal charge the charge will finally stop when it reaches down to 1/10 of the set current, i.e. 0.25A if you charge at 2.5A. For the 20 foot wire mentioned above there will only be a voltage drop of 0.025V at that final current - not worth worrying about.
   

If you have any questions about the manual don't hesitate to ask. The most important settings are how to turn off the infernal beep when you press any key, and to prevent the buzzer from going non-stop when it finishes the charge!

 

Michael

 

OK Michael,

 

Thats very reassuring all i need to get my head round is the actual charging programme and as you told me in a previous post use the LiPo programme and bobs your uncle, I will email the dealer and ask for a photo of the plug to the bike battery then I can obtain a couple here and have them ready to make into leads as soon as I arrive back in UK late April as I want to get over to Ireland before it gets too busy.

 

I cant see a Private Message facility on this forum how would I get hold of you if I have any further questions? Just post on this thread?

 

Thanks to your help I have decided to go down this route but without it I think I would have given up, your help was like me trying to explain mobile phones and how to use them to my 87 year old mother (I gave up)

 

Peter

Peter, not a problem at all. I've sent you a message (go up to the envelope symbol top right to see conversations or to start a new one) so you can contact me if you need.

 

Yes, just use the LiPo programme. You won't be balance charging as I say, you'll just be normal charging so you just need to follow the steps at the top of page 15 of the manual - "Charging a Lithium battery in normal CHARGE mode".

 

Hope the preparations for your trip go well!

 

Michael

I'd be interested to know if anyone has worked out a way to use these chargers on the Bosch batteries. The standard charger has 3 pins and gives 5 volts to the centre pin, and nothing to the main positive pin whilst not plugged into the battery.

I believe the battery uses a communications bus to talk to the rest of the bike electronics - the ubiquitous CAN BUS. The 5V is probably to initiate comms with the electronics in the battery. Does the battery have any voltage on its main positive pin when not plugged in to anything?

I believe the battery uses a communications bus to talk to the rest of the bike electronics - the ubiquitous CAN BUS. The 5V is probably to initiate comms with the electronics in the battery. Does the battery have any voltage on its main positive pin when not plugged in to anything?

 

nothing, the battery has 5 connections, the bike has 4 pins, only the charger uses the central battery connection.

If you want to use anything other than the Bosch charger, you need to wire it directly to the BMS or cell-pack. You could probably also charge through the discharge cables, but the battery would have to be switched on first.

Thanks I knew it wouldn't be simple.

what would be the solution for 13S? To recharge on of these - http://eclipsebikes.com/116ah-lithium-frame-battery-samsung-cells-p-1105.html

 

I have the batteries and panel already just need a 12V charger but can't seem to find anything above 10S on hobbyking....

To be honest I don't know of any 12v chargers that will do above 10S. You might have to go the inverter route to charge a 48V battery unless you strike lucky elsewhere.

 

Michael

Following on from this old thread, I want to charge a Bosch 400 battery from the batteries in the camper van when away. I know I can pay £150 (ish) for a Bosch 12v charger that will do only one thing - and slowly. I would rather put the money into an inverter to run the standard charger which could also be used for other things. I know I will only get 80% efficiency but I do have 2 batteries and 200w of solar on the roof - plus I would tend to charge whilst travelling around so alternator going as well.

 

My question is, do I need to use a Pure Sine Wave inverter and how big an inverter do I need?

 

Many thanks in advance.

 

Kendalian

Following on from this old thread, I want to charge a Bosch 400 battery from the batteries in the camper van when away. I know I can pay £150 (ish) for a Bosch 12v charger that will do only one thing - and slowly. I would rather put the money into an inverter to run the standard charger which could also be used for other things. I know I will only get 80% efficiency but I do have 2 batteries and 200w of solar on the roof - plus I would tend to charge whilst travelling around so alternator going as well.

 

My question is, do I need to use a Pure Sine Wave inverter and how big an inverter do I need?

 

Many thanks in advance.

 

Kendalian

... I just answered this on another thread. The Bosch expects to see 220v and will draw a max of 1.5amp , it is expecting to see a sine wave, but I am speculating here and expect it does not matter whether it is driven by a square or sine wave . It will be going into a switch mode supply anyway.

It expects to output a voltage of 36 to 41 volts at a maximum current of 4 amps

Peak power drawn is 330w and peak output power is 165w . Again I am speculating, but I suspect that the peak input power of 1.5amp would refer to inrush current and that probably power input is around 200w. Certainly my charger does not feel as it is outputting 200w of heat.

I am confident that a 350w inverter would do the business.

Thanks Danidl, I did see your reply in the other thread after I posted here. I'm still unsure about whether a pure sine wave inverter is needed - I wouldn't want to damage a brand new Bosch battery. I did e-mail Bosch but they only 'helpfully' replied to get one of their 12v chargers!

 

Cheers

 

Kendalian

Thanks Danidl, I did see your reply in the other thread after I posted here. I'm still unsure about whether a pure sine wave inverter is needed - I wouldn't want to damage a brand new Bosch battery. I did e-mail Bosch but they only 'helpfully' replied to get one of their 12v chargers!

 

Cheers

 

Kendalian

.... Well as a famous person once said, they would say that wouldn't they ,.. but seriously, i cannot see why a square wave would be in any way detremental to the Bosch charger. All of these switch mode devices comprise a diode bridge and a high voltage capacitor before the switch and transformer, and the diodes and capacitor components will not affected by square voltage waveforms.

Was interested by this thread so did a bit of reading.

 

This link involves a laptop charger and is worth a scan considering the cost of Bosch battery chargers.

 

http://electronics.stackexchange.com/questions/128365/could-a-modified-sine-wave-inverter-destroy-damage-the-ac-adapter-for-a-laptop

Was interested by this thread so did a bit of reading.

 

This link involves a laptop charger and is worth a scan considering the cost of Bosch battery chargers.

 

http://electronics.stackexchange.com/questions/128365/could-a-modified-sine-wave-inverter-destroy-damage-the-ac-adapter-for-a-laptop

 

That is an interesting link. The waveform shown is not what I would have understood as a modified sine wave . That is the ordinary square wave , there needs to be a dwell state at the end of each transition when all the driver transistors are in the off state in order to prevent a short of power to ground in case one of the transistors is tardy.

The reference to voltage overshoot may be a switching transient, but is just as likely to be an artifact due to unforeseen compensated probe.

A true modified sine wave generator will be use pulse width modulation using a very high speed switch in order to mimic the power output of a sine wave .. full voltage narrow pulses for the lower voltage and wider pulses of full voltage towards the peak.

Anything with "DrFriedParts" in is a must read in this household.

Anything with "DrFriedParts" in is a must read in this household.

... I have been doing some more reading and remembering.

In the remember category, i once drove accross Ireland using a laptop computer in the car powered by one of those low cost inverters, and the laptops battery charger. The laptop was an adli purchased medion brand. I was using it as a GPS system . The only casualty was overheating in the cigarette lighter socket, both charger and inverter are still ok. This was a 6 to 7 hour charging event

 

What seems to be passing as" modified sine wave " Is a marketing term for square wave .

 

Reading again the article referred to , i suspect that the invertor was incapable of supply of sufficient power to the battery charger, it was therefore trying to engage the start up sequence with low voltage and driving excessive current into the switching transistor. The transistors was not getting into the high efficiency saturated state and consumes much more energy. Power engineers would call this a " brown out "

I'm a pretty careful guy at the best of times so I think a pure sine wave inverter is the way to go for safety. I'm thinking one of these 600w models which will enable me to charge 2 batteries at once.

 

http://www.armcoshop.co.uk/products/soft-start-pure-sine-wave-inverters-652-102uk.html?gclid=CNe4s5r72tICFQU8GwodYVUD4g

 

Cheers

 

Kendalian

I'm a pretty careful guy at the best of times so I think a pure sine wave inverter is the way to go for safety. I'm thinking one of these 600w models which will enable me to charge 2 batteries at once.

 

http://www.armcoshop.co.uk/products/soft-start-pure-sine-wave-inverters-652-102uk.html?gclid=CNe4s5r72tICFQU8GwodYVUD4g

 

Cheers

 

Kendalian

... Good call, 600w one will allow you to use a power tool eg a drill or jigsaw as well as charging the battery. Note you would need to have either the van running or your solar panels assy charged , as the device will be drawing nearly 700w or nearly 70 amps at 12v ... very Thick cables at the low voltage input as well. Best of luck!

... 70 amps at 12v

 

!

 

now thats a charger

... Good call, 600w one will allow you to use a power tool eg a drill or jigsaw as well as charging the battery. Note you would need to have either the van running or your solar panels assy charged , as the device will be drawing nearly 700w or nearly 70 amps at 12v ... very Thick cables at the low voltage input as well. Best of luck!

.. I am not big into car parts, but I suspect that 600w of additional load on an alternator may be excessive. My reading suggests that normal ones are rated at 55 to 75amp, and only special vehicles ( jeeps, mountain rescue, military) have larger rated ones for winches etc. So charging a single battery would be more prudent. A power tool could be used as by its nature it is intermittent and the car battery can take up the slack.

Yes - I think you're right, though the Renault Master which the campervan is based on does have a 150 amp alternator. Again my carefullness suggests one battery at a time! I will probably get the 600w inverter and see what power it pulls when charging one battery (via the van's NASA BM1 battery monitor), then maybe consider charging 2 at a time.

 

Kendalian