Input voltage/amps for the Emag board...

[Evil Bob]

I'm looking for the input voltage/amperage for the Emag board and solenoid, need to do a little math with the Emag battery (16.8/650ma).

I have everything I need to wire up both my warp and halo (both running at 12v regulated) and running all everything off of the emag battery to save weight, just holding off until I know that I won't be overdrawing the battery, last thing I need is thermal meltdown while playing.

-Evil Bob

[Muzikman]

The Emag batt can not power the Halo, don't even try. You can how ever power the gun, Warp, and Revvy off the Emag batt.

[Evil Bob]

Originally posted by Muzikman
The Emag batt can not power the Halo, don't even try. You can how ever power the gun, Warp, and Revvy off the Emag batt.

Really? I fail to see why it won't work, considering you can power the halo off of a single 9v battery which puts out a measily 150ma, it's not recommended but it does work.

Also I'll have 12v at 650ma as the input which is more then sufficient to power the halo.

-Evil Bob

[Muzikman]

What are you going to use to regulate the Emag batt down to 9v for the Halo to run off of?

Remember, the Halo runs at only 9v but very high mAh.

[SlartyBartFast]

Knowing the specs of the Halo, it should be possible to have a voltage regulator to drop the voltage and capacitors to provide the required high current.

[314159]

capacitors can supply current in short bursts, but then they suck a lot of current to charge up. capacators would not be good for things that continously require a large amount of current, (like a halo continously running durring rappid fire).

a capacitor would be good for things like a solenoid to trip the sear, because it is active for only a fraction of the firing cycle, and can charge whenever the solenoid is not active.

[cledford]

RobAGD runs his revi and warp off of the emag battery. Do a search for a link to his website, there is a FAQ with pics there...

-Calvin

[SlartyBartFast]

Originally posted by 314159
capacitors can supply current in short bursts, but then they suck a lot of current to charge up. capacators would not be good for things that continously require a large amount of current, (like a halo continously running durring rappid fire).

I realise that. However, the largest draw the HALO will require is at start-up. Without hard data, it's hard to say if the current draw under continuous fire is a problem or not. Of course, depending on the capacitors used strings of shots may be possible.

I do believe that some current draw data was posted in another thread. Does anyone have it?

[athomas]

If the Halo will run off a regular 9v battery, it will most certainly run off an emag battery regulated down to 9v, even with the existing current draw of the emag.

[Kevmag]

I have a E-mag battery harness to power my warp and revy off the E-Mag battery. The warp side has a voltage regulator and the revy side doesn't (revy board is reg down to 12V), which, I assume would cause problems with the Halo.

You're more than welcome to take a look at it.

Kevin

[Muzikman]

The Warp/Revvy conncetion is easy, it's the warp/halo. I still do not know anyone who has tried, and in talking to RobAGD at Madness last year, he said he did not think it was possible. As for running the Halo off a single 9v, doesn't it say on their website and even in the documentation NOT to do this?

[SlartyBartFast]

Originally posted by Muzikman
As for running the Halo off a single 9v, doesn't it say on their website and even in the documentation NOT to do this?

Well, it would nice if anyone could give us real numbers because we're all just wildly speculating.

We need to know if the high current draw at motor startup is the main requirement for AA bateries and not a single 9-volt or if it is the steady state current draw.

In other words, does low/insufficient amperage potential adversely affect the HALO motor startup/acceleration or does it hamper the top speed?

[Muzikman]

Well, maybe Chris will stop by and answer. Once I get home I will email him and find out. But either way, does it really matter? I mean you are going to want to shoot long srings of balls, so if that's it, then there ya go. If it's the motor starting up, well it's always going to be starting and stopping during a game so that's out too.

If someone wants to try it, go ahead and give it a shot, but rememeber, you still need to cut the Voltage from ~18V down to 9V and still keep the high amps. Find a voltage reg that can do that.

[Evil Bob]

I know the halo A needed alot of amperage for the gears it used, upgrading to the B with the belt drive improved battery life, so it's safe to say that it takes a bit less amperage to power the B then the A. I'll email the guys over at Oddessey and see if I can get some solid facts on it.

I've already wired up my Warp with a 12v reg and on/off switch, I'm hoping I can feed 12v directly into the HALO without causing any damage to the board, I'll post any info I get back from Oddessey.

-Evil Bob

[hitech]

Originally posted by Evil Bob
I've already wired up my Warp with a 12v reg and on/off switch, I'm hoping I can feed 12v directly into the HALO without causing any damage to the board...

Did you know that you will need a capacitor across the output of the 12 volt reg? You get to much noise without it. It may work for a while, but will give you trouble later.

I wouldn't run 12 volts into the Halo unless the guys at Oddessey say it is okay.

[Evil Bob]

Originally posted by hitech


Did you know that you will need a capacitor across the output of the 12 volt reg? You get to much noise without it. It may work for a while, but will give you trouble later.

I wouldn't run 12 volts into the Halo unless the guys at Oddessey say it is okay.

Yep, I have 100mf caps on both sides of the 12v regulator, the warp spins smooth as silk.

Waiting on info back from Oddessey on whether I can safely put 12v into the halo or not.

-Evil Bob

[Evil Bob]

Okay, got an answer back from Chris at Odyssey, he basicly said that anything over 9v into the HALO board was a bad idea, for amperage 500-1000 would be a good starting place.

I did some digging around on the net and found a 9v 1.5a voltage regulator ($0.52 each) that will do the job nicely and some 25v 100mf capacitors ($0.06 each). Now I'm looking for a transformer I can use to up the current into the halo to go from 650ma (emag battery) to a little over 1a (6AA's x 1700 = 1.02A). Should have some part numbers and a schematic put together by this evening on how to setup a full circuit for running the halo off of an emag battery.

-Evil Bob

[athomas]

If you are planning on using the emag battery for driving the gun, warp and halo, then you have to know the maximum current draw when all devices are running at the same time and the capability of the cells to provide the current requirement. The capacity of the cells are 650mA but the ability of the cells to produce instantaneous current is much higher. The emag battery pack has a high current capability but I'm not sure the exact Amp value.

[Evil Bob]

That's the purpose of this thread, to find out the draw of the Emag board (which I have yet to determine). I have the answer already for the Warp (250ma) and the Halo B(500ma-1a).

I have successfully powered all three devices for a very short term using the proper voltage regulation. Supplying current to all three devices in the long term will most likely result in damaging the emag battery from over drawing it, being that the required amperage is too high for the power source. Fortunately the Emag and the HALO both pulse, which reduces the constant current draw.

I'm am currently shopping around for a capatible battery with a larger current capacity to safely power all three devices without adding any additional weight.

I am also working on a possible solution to safely use the existing battery.

-Evil Bob

[hitech]

I believe the eMag battery is a 650 mah (milli amp hour) battery. That number refers to the batteries overall capacity. It is NOT a reflection of how much current you can safely draw. Research AAA nimh battery specs. That is what the battery pack is made from.

Added:
Okay, I found some information for you. Based on the eMag battery being 650mah you should be able to safely draw 1300ma.

Taken from http://www.hynergy.com/Tech_NiMH.htm

2.3 High-current discharging
As high-current discharging can lead to heat generation and decreased discharging efficiency, consult Hynergy before attempting continuous discharging or pulse discharging at currents larger than 2 CmA.

Note : "CmA"
During charging and discharging, CmA is a value indicating current and expressed as a multiple of nominal capacity. Substitute "C" with the battery's nominal capacity when calculating. For example, for a l500mAh battery of 0.033CmA, this value is equal to 1/30 ¡Á 1500, or roughly 50mA.

[Evil Bob]

Thanks for the info Hitech, appreciate it.

Grabbing some paint on the way home, I need to check the amperage values under operating load, give the motors on the warp and halo something to work against for some actual real world values.

Also found a rechargible LI battery that outputs 16.8v 1Ah that is used for pace makers that I'm taking a serious look at as a potential replacement if I encounter any heat/over drawing problems with the current emag battery pack.

-Evil Bob

[athomas]

LI batteries typically don't have as high an instantaneous current capability (C rating) as Nickle based batteries.

[Evil Bob]

Not too worried about the instantaneous output, I'm more worried about the overall constant draw and whether I damage the battery or not. If the LI battery has a bit lower top end, that's fine as long as it can keep up on the long term with the draw requirements.

I'll have more firm numbers tonight when I test the devices under load and get numbers for actual draw on all three.

-Evil Bob

[hitech]

Originally posted by Evil Bob
Also found a rechargible LI battery that outputs 16.8v 1Ah...

You CANNOT use a LI battery to drive the eMag. I asked Tom why he didn't use them in the first place. They will NOT deliver enough current for the solenoid. Remember, the rating is the capacity of the battery over time. The amount of current you can draw is different for nimh and LI. LI is MUCH less. It just lasts a lot longer.

If the battery doesn't heat up too much (they can get warm, just not hot) then you are probably okay. A spare wouldn't hurt. :D

[Nobody077]

Quick thought on the 9v 1.5amp regulator that rateing is most likely with propper heatsink/cooling. The "bare" regulator rateing is probaly closer to 750ma. To get the full 1500ma you will need a heatsink probaly the size of a 9v battery reciveing good airflow, this kinda kills all weight saveings.

[314159]

Originally posted by Evil Bob
. Now I'm looking for a transformer I can use to up the current into the halo to go from 650ma (emag battery) to a little over 1a (6AA's x 1700 = 1.02A). Should have some part numbers and a schematic put together by this evening on how to setup a full circuit for running the halo off of an emag battery.

-Evil Bob

transformers do not work for dc, you need ac to make a transformer work. you can modulate dc voltage and run it into a transformer.... but you cannot get out near what you put in (think of the area under the graph of the curve representing voltage, compared to the area under the curve of a straight dc signal).

i think that the easy solution would just to make a pack out of nimh aa cells, and slip it under the tank cover, and ditch the emag batt pack. (but if you are trying to do this to save weight.....

[Evil Bob]

I'm currently researching methods to increase current such as is used in stun guns and radio transmitters and voice coils running on a DC source. If that doesn't pan out with something reasonable, I'm considering ditching the emag battery and going to AA's, which will still keep me happy in that I won't need to carry three different types of batteries.

Litium based batteries are showing quite a bit of promise, considering I'm looking at a battery pack (AA cell based) that has very long life, is light weight, and puts out a nice high current pulse (powers a pace maker) that will do what I'm looking for, especially considering that the emag solenoid and the halo both pulse. The warp doesn't chew enough current to be any real concern. The only real concern here is the cost of the LI batteries which are substantially more then what the emag battery goes for.

-Evil Bob

[Muzikman]

Or you can just run the Halo off 6 - AA NiMH batteries;)

[314159]

stunguns have a oscilator that drives a transistor/mosfet that switches the load going into a transformer to step up the voltage, then the voltage is increased with a capacitor/diode multiplier.... stun guns are also high voltage/low current...

i suppose that you could look into dc to dc converters.... you can buy them for about 15 bucks from digikey, with 90%ish effency.