running the OI off a battery

We need to run the robot on radio while away from the plug. I went out and bought an M-type connecter (the kind that the DC-In port on the OI uses) and soldered it to a 9 volt battery (cause the power adapter SAYS it outputs 9v)

but the problem is, that, when tested with a multimeter, it shows that the power adapter ACTUALLY outputs 12 volts.

will the OI run on 9 volts?

Well, from the writing, the power adapter says it outputs 9VDC, 1500 mA. I would assume 9V would work, but I’m very puzzled as to why the multimeter gave you a 12V reading… Try it again; maybe you had something messed up.

well, it makes sense, considering the OI gets 12v through the tether and the competition port.

though don’t know why it says 9 on the adapter.

*Originally posted by Aonic *
**We need to run the robot on radio while away from the plug. I went out and bought an M-type connecter (the kind that the DC-In port on the OI uses) and soldered it to a 9 volt battery (cause the power adapter SAYS it outputs 9v)

but the problem is, that, when tested with a multimeter, it shows that the power adapter ACTUALLY outputs 12 volts.

will the OI run on 9 volts? **

The OI should run on 9 volts, however I’d be surprised if a 9v battery lasts more than about 10 minutes! You’d be much better off hooking it up to a spare robot battery (it’d be a good idea to put a fuse in the line if you do this though).

The reason the OI power supply seems to put out 12v (I actually measured ours at 14) is that it’s an unregulated supply and will output a higher voltage when there’s no load connected to it (credit this answer to Al S. as I just asked him the same question last week!).

haha. the 9 volt didn’t last very long (about 5 min) and the OI started doing constant resets after a while (PO5…5…3…2…1…1072…PO5…etc)

after discovering that, we made a quick run to radio shack, found a aligator-clip to car-12v-socket adapter, and a car-socket-adaptor to 9volt Mplug adapter (for about 20 bucks total) hooked em up to a 12volt battery, and used that :smiley:

anyway, thanks for all your help! =)

Why not just power it through a competition port dongle?

All you need then is a 25 pin connector (or a 25 pin cable chopped in half) and a battery.

shrug seems cheaper, and you can put in switches for disable and auto mode while you’re at it. It’s something I’ve been meaning to do for a while now. I would like to find a better power source, something in between a 9 volt dry cell and a bot battery. I was thinking an old laptop battery, although it is rated at 14.4 volts. I know nothing about the power system of the RC, so I won’t try it, yet.

But it would be so cool.

Maybe if I get bored in the pit…

-Andy A.

Last year we had a switch on our control board that would switch the power from a surface mouned plug for the wall wart adapter that the OI normaly uses to a bunch of AA batteries we had under the top of the board…very useful when doing demonstrations, or just to drive your robot around to move it from point A to Point B

*Originally posted by Andy A. *
**Why not just power it through a competition port dongle?

All you need then is a 25 pin connector (or a 25 pin cable chopped in half) and a battery.

shrug seems cheaper, and you can put in switches for disable and auto mode while you’re at it. It’s something I’ve been meaning to do for a while now. I would like to find a better power source, something in between a 9 volt dry cell and a bot battery. I was thinking an old laptop battery, although it is rated at 14.4 volts. I know nothing about the power system of the RC, so I won’t try it, yet.

But it would be so cool.

Maybe if I get bored in the pit…

-Andy A. **

Comp Pport has a 15 pin connector !

Crescent (#610) has used a battery pack for several years; a battery holder with AAA cells and a connector that goes in to the power connector used by the 1500 mA Wall Wart IFI supply. I don’t know if they use 6 or 8 cells in series.

It seems reasonable that IFI would use a regulator on the power input, so it might not matter. but the power input is a diode away from the tether power supply line.

Practically every Wall Wart gives the rated voltage only if loaded down to the rated current, depending on the resistance of the transformer secondary for this “regulation”. I’d design the “9 V” input to handle 12 V at least, and the 7800 Regulator line can handle 18 V max rated.

We have used a power pack to run at many outdoor events with our machine…we use four 9 volt batteries hooked in parallel which gives us a good amount of run time on the interface.

*Originally posted by Andy A. *
**Why not just power it through a competition port dongle?

All you need then is a 25 pin connector (or a 25 pin cable chopped in half) and a battery.

shrug seems cheaper, and you can put in switches for disable and auto mode while you’re at it. It’s something I’ve been meaning to do for a while now. I would like to find a better power source, something in between a 9 volt dry cell and a bot battery. I was thinking an old laptop battery, although it is rated at 14.4 volts. I know nothing about the power system of the RC, so I won’t try it, yet.

But it would be so cool.

Maybe if I get bored in the pit…

-Andy A. **

Be careful when you do that. Innovation FIRST will void your warantee if you try to power it through the Competition port on your own, and it screws up. From what I can tell you, the OI gets its power from Pin 1. I believe when you power the OI from the Competition port you un-lock more channels than you get with a regular dongle. To check the voltage of the OI you can measure it from Pin 1 to a ground (Pin 8).

The wall power supply for the OI (like most brick style plug in power supplies) will not regulate properly with no load. So if you took the voltage reading with a multimeter while you wern’t drawing any current off of it, it will read abnormally high. If you were to test it under load, I would bet the voltage would drop to ~9V.

Correction to CAMTUNKPA…

We use 3 9 volt batteries hooked in parallel. Yes and when the batts die the controller cuts out.

I have used 12 volt power packs plugged into the operater interface and it does not seem to harm them…

i dont have one of the powers supplys on hand, and so i have a question, Which part of the plug is positive and which is negative? i need the info to build one.
thanks

We’ve been using an old (can’t hold a charge, etc etc) robot battery to power an equally old OI. It’s been working since December, and we only charged it once. :smiley:

*Originally posted by ZACH P. *
**i dont have one of the powers supplys on hand, and so i have a question, Which part of the plug is positive and which is negative? i need the info to build one.
thanks **

The center contact is negative, and the outside is positive.

Thank you gwross.

*Originally posted by gwross *
**The center contact is negative, and the outside is positive. **

Are you sure? Generally on power supplies like that, the outside is negative. This post says the same thing (although it is old): http://www.chiefdelphi.com/forums/showthread.php?s=&threadid=11422&highlight=power+adapter

Last year we planned on running our robot in a local parade. I e-mailed IFI and this was their response:

‘12V is the max. I know that radio Shack carries a 9.6V battery pack that we use here and at competitions. You will have to modify the connector to fit the OI. This battery pack is like a 4-pack of AA’s. Radio Shack also carries a charger for this pack. The connector is a 2.1mm X 5.5mm.’

I do not remember +/- but we ran the robot over a mile without the OI shutting down using this battery pack.

*Originally posted by Joe Ross *
**Are you sure? Generally on power supplies like that, the outside is negative. This post says the same thing (although it is old): http://www.chiefdelphi.com/forums/showthread.php?s=&threadid=11422&highlight=power+adapter **

Joe, I have a 12V, 0.5A power supply on the shelf beside me - it gives 19 V OC, and the still attached factory plug on it, which fits the OI power input, is pin-negative. As Apple’s monsieur* Gasse’ said, “The nice thing about standards is, there are so many of them.” I label my supplies with a labeller, now.

BTW, the supply works well as is with a Radio Shack powered speaker. (All by way of saying, don’t expect much adherence to “standards” when dealing with commodities from offshore.)

*Jean-Philllipe, maybe, I forget.