question on charger upgrade

[RC Accessory]

Originally Posted by equalizer

Evan, maybe you could answer my two questions on the Bantam -

1) any plans on one that goes up to 20 amps output?
2) does the charger sense its input wattage (for DC) or if its running off its AC (and what its wattage is) and only allow charge rates as appropriate, or is it up to the user to look up the appropriate maximum output in the instruction manual?

I do agree the Bantam has a really nice display, and it's good to know all can be set from one screen! (and again I really love those graphs, any gearhead appreciates features like that!)

1). That I do not know.
2). You set the charger to what you want to charge at. You are only limited by the output wattage. If you are referring to the charger limiting the output based on the power supply, then no. I think only Hyperion has the that feature. If you are referring to the power output based on the input voltage, Bantams don't work that way. Bantam's rated power outut is the same if you use 11V power supply or 15V power supply. Hyperions and iChargers use a much less expensive chipset that requires higher input voltage to achieve the wattage. This is not that bad if you have the power supply. If you run off DC, then the chargers output is reduced.

[equalizer]

I remember the manual said that, with the built-in transformer, the output was diminished a bit; so I guess the charger knows its running off the transformer, and limits the output options?

I see what you're saying on DC - it doesn't need higher voltage to service the output range. And there's no way it can know what you have it plugged into - so if you try to pull too much amperage for what's driving the input, that's user error at that point, right, regardless of the charger being used?

What would happen if you overloaded the input, anyway (like doing a 12 amp charge off an 8 amp power supply)? I am assuming the power supply would get hot and hopefully shut itself off? What if it's a 12 volt battery - it would just get all its juice sucked out?

[TJinGuy]

Thanks for the reply Evan, they do sound very feature filled so I take that one statement back.

I think what equal is getting at is do you have to tell the charger whether it is running off AC or DC due to the wattage difference? I saw in the manual that it did have a 3 icon screen where it let you choose, so I would say yes but not positive.

Maybe also what he is asking is if the charger is smart or just allow any old charge rate to be selected even if there is no way it can output it. Like the not go powerful TP610c says it will output 10A and will let the user select 10A as a charge rate but with an 80W max output it can't even finish a 2s pack at 10A. So does the Bantam unit do the math and limit your options?

On the voltage input thing, I firmly believe it is not a quality of electronics thing but rather a design decision. Given that these chargers are more efficient at higher input voltages, then why not allow the user to take advantage of that? I know that the 208B will output about 280W at 12V, so they could have teken the Bantam route and just rated the charger at 280W. That would cover it no matter what the input voltage was. But they didn't they have effectively given the user the option for 350W IF the correct power supply is used. Bantam could have done the same thing. Like I said, it is a choice the manufacture makes. Being a tinker I prefer the option of more wattage but some want to know it will always have the same no matter where yo uplug it into.

[equalizer]

Chris is right, those are exactly the things I was trying to figure out. Again all the info is much appreciated!

[RC Accessory]

Originally Posted by equalizer

I remember the manual said that, with the built-in transformer, the output was diminished a bit; so I guess the charger knows its running off the transformer, and limits the output options?

I see what you're saying on DC - it doesn't need higher voltage to service the output range. And there's no way it can know what you have it plugged into - so if you try to pull too much amperage for what's driving the input, that's user error at that point, right, regardless of the charger being used?

What would happen if you overloaded the input, anyway (like doing a 12 amp charge off an 8 amp power supply)? I am assuming the power supply would get hot and hopefully shut itself off? What if it's a 12 volt battery - it would just get all its juice sucked out?

Yes and no. When on AC or DC, the charger does know and shows on the opening screen if it running on AC or DC. The charger does have a 10 amp limit and yes you can set it for 10 and set it for 8 cells, but you are limited to wattage of the charger, AC or DC powered.

If you over drew the amps on an external power supply, the power supply's voltage would drop. Once the input voltage drops below 11V, the Bantam charger will reset. As far as AC power goes, the charger knows its on AC power and will not allow the internal power supply to be over drawn.

[TJinGuy]

It sure would be nice if chargers did the math for you and let you know the actual max charge rates when you go to charge. It would stop a lot of confusion from TP610c owners for sure. I wonder why they don't do it?

[RC Accessory]

Originally Posted by TJinGuy

It sure would be nice if chargers did the math for you and let you know the actual max charge rates when you go to charge. It would stop a lot of confusion from TP610c owners for sure. I wonder why they don't do it?

Actually it is a great idea. Part of the problem is Marketing. Some chargers market it and the way they promote is a 6 cell charger @ 10 amps. I see it all the time on the various boards.

In the back of the Bantam manual, they list per cell and by chemistry the max charge rate is. That also has presented problem withs users as I once had a customer think that was the recommened charge rate! No matter what is done, you'll have the same amount of questions, just different ones.

Today I spend the day at the IRCC Heli fly in. There was some incredible flying going on. My favorite manuver that I saw the same pilot do twice was the backwards inverted auto. But this pilot came down fast and then leveled off parallel to the runway @ 3', then rolled it upright and touched down like a feather. Off to take my wide out to a nice dinner as she hung with me all day at the field.

[equalizer]

Chris, I just saw that the Hyperion 1210i is on sale at All e RC:

http://www.allerc.com/product_info.p...oducts_id=2785

I think this is an older model, but is there anything this is lacking? It can go up to 180 watts out! Plus it has the feature to set the maximum charge percentage, to facilitate storage as well as 90% charging (rather than 100%).

Any reason I'd choose the 106B over this?

Convenient too, because All e RC is where I am planning on getting several new Hyperion batteries from!

[equalizer]

Ah wait, I think I get it - this charger is so old it does not have the balancer built in? The balancer has to be bought separately and plugged in, I see. Man, and I was getting excited!

[TJinGuy]

Yeah that is an older model Hyperion. I have no doubt it is a nice unit but you are correct, it requires 1 or 2 balancers (depending on what you are charging). Many new charger have adjustable final voltages including the iChargers. They, like the Bantam, also have a specific store charge mode.

[equalizer]

Hmm, after more research, I see that one can get it WITH two external balancers for $120 (or one balancer for $100):

http://www.aircraft-world.com/shopexd.asp?id=4901

I assume there's nothing the internal balancers on newer models do that's more efficient, just cleaner in terms of the wires and such. So this might still be a nice option (especially considering that with two balancers, one can charge two 3S packs at once).

[TJinGuy]

I am not sure about that. I think the second balancer is just for cells 7-12 but I am not for sure. The question I have is why would you save $20 to get a charger with an external balancer and only 180W when you could have a 106B+?

[equalizer]

I can't find it now, but there was another thread on here demonstrating how it could charge two packs at a time using two external balancers.

Cost-wise, I factor in the cost of a power supply also when comparing to the iCharger. I mean, I guess I could keep my current, 8.5 amp supply, but that's not enough to get the full output from the iCharger. I know a 30 amp PS is just $30 on Progressive, but if I get another external PS, I'd rather get as big as possible for the future, like the $70 P350:

http://www.progressiverc.com/index.p...emart&Itemid=1

I guess I was thinking too that this Hyperion would be a nice all around charger for smaller packs in general, since at the field, I might not even want to be balance charging (yet I'd still have a compact AC input option at the field, if AC is available). Then later on I could get a 208B if I really need more output (or still consider a Bantam based on what updates they have at that time).

[TJinGuy]

The 1210i is not an AC capable charger though? So you would still have to have a 12V (or more) source for it. Also nobody says you have to use the full output of any charger, so any of them will work on your current PS, you will just need to keep your charge rates down. Then later you can buy a larger PS if you find you need it.

Really aside form the fact that it will charge 12s packs and that it is cheaper cause it doesn't have a internal balancer, I don't see the draw of the 1210i. I only balance charge my packs cause that is just how I am, so there is no way I am going to buy a charger without a built-in balancer. But that is me and maybe you have different needs.

[equalizer]

According to this listing it is AC/DC:

http://www.hobbypeople.net/gallery/963155.asp

Do you think that's inaccurate? Of course if it's DC-only, then that's not an option at all.

Also, if you're only going to charge to 90%, and if you want a faster charge, isn't non-balanced the way to go? Otherwise, I'm just like you - I like to balance every time, currently (but my charger doesn't have a way to cutoff automatically at 90% - if it did, I'd probably go with an unbalanced charge to 90% for speed, since it's unlikely the cells will ever be so unbalanced that one will get above 4.2 volts if they're only being charged to an average of 3.8 volts per cell).

[TJinGuy]

I just don't know man, I know that some of the Hyperion chargers come in a DP (dual power) model but I did not think the 1210i did. I have done lots of searching and I have seen several people have the same info you have linked to but no other info supporting it. Also I search lots of photos trying to find a pic of the AC input and failed there too. I also tried to find the manual but can only find the 1210i DC manual. One other thing is the title says DC charger but then they say AC/DC in the description. I am just going to assume it is a misprint and it really is a DC charger just like 90% of the chargers out there.

Oh and on your 90% charge thing, the final voltage will be more like 4.15-4.18V, not 3.8V. 3.8V is about 50% charged.

[equalizer]

You are right - I stopped by the LHS and it indeed is DC only! Well that myth is busted, thanks again for alerting me to that!

Also, yeah, my fault on the voltage. I knew that seemed too low, I took 10% of the total voltage instead of the delta from a depleted pack to a full!

[TJinGuy]

Even the then the voltage is far from linear. Glad to hear you figured out the charger thing.