RunRyder - Whats it all about, 1C, etc etc need some tech info ??

rrTV-PHOTO

New HD TV

HOME rrTV-PHOTO GALLERIES MY GALLERY HELP-FAQ

myHOME PM pmRR MEMBERS 631 ONLINE 20 EVENTS SEARCH REGISTER START HERE

1 page

491 views

POST REPLY

Futaba-RC	.	A Main Hobbies	.	Boca Bearings
	.		.

e-Electric Batteries & Chargers > Whats it all about, 1C, etc etc need some tech info ??

heliraptor
Key Veteran
Location: Colchester, Essex, UK

Hi

Newbie on the Electric side here, I've been reading as much as I can, have a Joker and the Orbit Pro with 1 set of 32 x2400 Nicads and 2 x 30 x3300 Nimh's.

I submitted another post about charging with the Orbit but after sitting down and reading the instructions and trying to get my head round it have some questions.

As the batteries had been cycled a few times already (not by me and only a few if that) I went by the instructions and used the Reflex soft charge to avoid the memory issue (I diont think these suffered that).

I checked the guide in the back, as I was charging say 36 volts itn said I could run up to 8A.

I used 7A and it all went pretty easy, at the end of the cycle the display was flashing, only took about 15 mins and put just over 1000mah in.

I did the same on all 3, and they all roughly took the same.

Now, where do I go from here???????????

Firdt thing when I get to the field do I 'peak' the batteries using the Fast Peak charge??????

I am flying tommorrow, I aim to use all three packs and run them down at the end of a flight in the hover. Is this recommended??

After the first one has finished, can I charge at the field ??

Do I have to let it cool ???

More importantly, what setting do I use to charge it at the field, there is a fast peak charge option???

Assuming I can.

When I get home, what is the best course of action for the batteries, do I leave them flat all week (Won't be flying again till next weekend, do I charge them on the fast peak charge, or do I use the Easy charge or Reflex Charge option????

Pleas excuse my lack of knowledge but I don't want to get off on the wrong foot and knacker a load of packs

I also want to get the best life out of them I can (For obviosu reasons)

I'd appreciate an answer to most of the questions so I can go out first thing.

One final question, well two actually, is it best to charge on the maximum setting (Say 8A) or use a lower setting.?

What does 1C relate to I have heard it used, I think its something to do with Mah of cells and charging rates but not sure.

Thanks very much in advance. Lot of questions here and I appreciate any help.

Lee

01-23-2004 Over year old.

HOMEPAGE

rscamp
Veteran
Location: Ontario, Canada

Wow! So many questions...

Don't sweat the "memory" thing. That's more for TX batteries and the like. If the cells have been sitting around for a long time, better to slow charge them (format) to balance them (balancing once a month or so is a good idea).

Your cells will reach 1.5V or so each when charging so you won't have 8A available.

If you only put 1000mAh in, hopefully the batteries were partially charged! It is best to charge the batteries just before use and store them discharged - especially the NiCds. The NiMH don't like deep discharge quite as much. I would now discharge them and see what the capacities are.

I don't recommend repeaking. Lots of people do it, but it is better to do a full charge when you need them.

Yes, you can run the packs down in a hover. This is a good thing to do, especially for the NiCds.

If you have a big field battery in good shape, you can charge at the field. Don't use the battery in your car!

Let the batteries cool a bit before recharging - maybe 20 mins or so. If you have a cooling tube you can reduce this time.

Use the auto (fast) peak charge setting at the field (again, you need a strong field battery for this).

When you get home, you don't need to do anything to the batteries for a week if you have discharged them in your heli. Just charge them up before your next flights!

You can hit the NiCds hard (use the NiCd setting and fast charge) with no problem. Depending on the vintage of your 3300 NiMHs, you may be able to do the same with those.

"C" is capacity. A current of 1C is 1 X the battery capacity in amps. For example, 2C charge current on a 1200mAh battery is 2400mA (2.4A).

Rob

01-23-2004 Over year old.

HOMEPAGE

iskoos
Key Veteran
Location: Orlando, FL

good job

Hey Rob,

Heliraptor got only one reply to his post but I think he just doesn't need another one.
The job is well done

01-24-2004 Over year old.

heliraptor
Key Veteran
Location: Colchester, Essex, UK

Hi

Thnaks for the reply Rob, picked up your other one too. It makes me feel a lot happier just knowing these details and gives me a better understanding of charging, just what I was after.

You mentioned charging NIMH's at 2C in the other post, correct me if I'm wrong here,

2C 3300 mah = 6600 mah which gives me a charge available at a max of 6.6A ????

You also mentiona charge rate between 1C and 4C, going basck to the 2400 mah Nicads, 4C is going to be somewhere like 9.6A, well knowing that I can charge at 8, is it okay to do that, I think common sense tells me its better to charge at a lower C rating, even 3C is going to bring it down to 7.2A.

I was confused looking at the table in the back of the manual, it shows max charge ratings and refers to voltage and makes no mention of mah's. Is it best to stick to the mah reasoning as described above??

Hope I'm right.

Thanks again for your help.

Lee

01-24-2004 Over year old.

HOMEPAGE

rscamp
Veteran
Location: Ontario, Canada

Thanks for the compliment iskoos.

Lee. Yup. 2C = 2 X 3300 = 6600 mA charge current. If these are new 3300s you may be able to go even higher. However, you can only do what your charger can do.

The charge rates are guidelines only. It doesn't make life any easier, but the reality is even batteries of the same chemistry can vary a LOT in their characteristics. It depends on their internal construction.

I have some AA NiMH camera batteries that won't take anywhere near 2C - they only like about C/2! The new ultra-low impedance sub C NiMHs are quite happy at 3C. But don't worry if you are under the 2C or 3C or whatever. As you say, lower charge current is safe.

The downside of low charge current is the pack will give you slightly lower voltage during discharge. Don't set the current too low. If the charge current gets too low, the peak detect charge termination won't work...

If you are referring to the bar chart entitled "MICROLADER pro CHARGING CURRENT", it is really showing maximum charge current capability of the charger at various voltages. The high end is power-limited - i.e. your charger can only put out 275W and since power is Current X Voltage (IV), the current must drop once the voltage exceeds a certain value.

mAh is a unit of Capacity. Capacity is Current X Time, hence the units of Amperes and hours...

Rob

01-24-2004 Over year old.

HOMEPAGE

heliraptor
Key Veteran
Location: Colchester, Essex, UK

Thnaks Rob

So charging a smaller 1700 mah Rx pack, is it best to charge that at 1C, or will it take higher??

Or........does the Orbit limit the charge rate to an acceptable level even if you select say 3.4 amps (2C)

Lee

01-26-2004 Over year old.

HOMEPAGE

rscamp
Veteran
Location: Ontario, Canada

Lee.

Oops. NiCd or NiMH? I'll assume AA NiMHs. I only use about 1/2C Reflex with the lowest (NiMH) peak setting on high-capacity cells like this that aren't designed for fast charging. .

Also as previously mentioned the Auto (fast) charge setting should not be used on these smaller cells.

Rob

01-26-2004 Over year old.

HOMEPAGE

nedyah
Senior Heliman
Location: South Australia

Hi,

My Orbit is not the pro version, but I think their the same except for the higher charge rate of the pro.

Could someone please explain what the 4 differant settings in the Auto fast Charging & delta peak mode. I know 2 are for NiMh & the other 2 are for NiCd. But what does "NiMh: ca. 3,5 mV/cell" & "NiMh+: ca. 5,0 mV/cell", etc mean.

Thanks, Hayden.

01-26-2004 Over year old.

rscamp
Veteran
Location: Ontario, Canada

Hayden.

I think your query is answered in this thread:
http://runryder.com/helicopter/p617...iraptor#p617403

Rob

01-26-2004 Over year old.

HOMEPAGE

heliraptor
Key Veteran
Location: Colchester, Essex, UK

Hi Rob

Yes the small ones are NIMH :-)

Thanks for the info, I read somewhere that NMH batteries should not be charged using the reflex charge, is this correct.

Also at 6 amps on the fast charge setting my 32 x 3000's NIMH are charging in around 45 mins, is this about right. I have the facility to set it at 8 amps on the pro but I'm worried about frying them, same for my 2400 nicads.

I was hoping to be able to shorten that time when at the field, only have 3 packs and it would be great to speed it up n the odd occasion.

Any thoughts

Lee

01-27-2004 Over year old.

HOMEPAGE

rscamp
Veteran
Location: Ontario, Canada

I haven't read that NiMH cells can't be charged on Reflex. But Reflex is really aimed more at NiCds.

Are you really limiting the charge current to 6A on the fast (auto) setting? With 30-32 cells, you probably can't go much above 6A (power-limit).

I charge a 24 cell RC2400 pack in about 26 minutes. You won't be able to do 32 cells quite as fast because you can't deliver 8A into that high a voltage. I would imagine my HR2600 cells take closer to 30 minutes. I don't have 3000 NiMHs, but if they are the new breed of NiMH cells you might be closer to 40 minutes or so due to the power limit with 32 cells..

Rob

P. S. Don't forget the power limit! :-)

01-27-2004 Over year old.

HOMEPAGE

heliraptor
Key Veteran
Location: Colchester, Essex, UK

Hi Rob

I'm afraid you've lost me again

Charge current v Charge limit.

So whats the best way to charge these cells, shall I use fast charge and the highest peak setting??

Or in reflex mode, leave it at auto or set a max ??

Sorry

Thnaks again though

Lee

01-28-2004 Over year old.

HOMEPAGE

rscamp
Veteran
Location: Ontario, Canada

Lee.

I didn't say charge limit. I said power limit. In other words, the limit to the amount of power your Orbit can deliver limits the current it can deliver at high voltages.

As I mentioned before, for fast-charge sub C cells, I would try fast (auto) and the "NiCd" peak setting. That's what I use. Make sure your NiMH cells are the new fast-charge ones. If they heat up a lot during fast charge (hot at the end is okay) they may not be, so be careful and reduce the peak setting if this is the case.

There is no "auto" in Reflex mode. The current you set is the current it will charge with. Use appropriate current settings for the size and type of cells you are charging. Remember the guidelines!

Rob

01-28-2004 Over year old.

HOMEPAGE

1 page

491 views

POST REPLY

Modefo's RC Helicopters	.	XHELI.COM	.	Autography FlightPower
	.		.

e-Electric Batteries & Chargers > Whats it all about, 1C, etc etc need some tech info ??

PRINT TOPIC

Advertisers

Subscribe to This Topic