 | | Overcharged battery?
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| I've got a pre-assembled Gleason Research HB with expansion board, and have a couple questions. We've left it plugged in (on normal charge mode) for a week or so. I started to look at the specs to hook up a Futaba servo (6V), and found that with no (...) (25 years ago, 15-Mar-00, to lugnet.robotics.handyboard)
| | | | | Re: Overcharged battery?
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| actually this is to be expected. with no load, the diodes produce no drop. if you're worried, try hooking a DC motor (or other real load -- light bulb, 10 ohm resistor, etc). across the servo motor supply and then measure the voltage. you should see (...) (25 years ago, 15-Mar-00, to lugnet.robotics.handyboard)
| | | | | Re: Overcharged battery?
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| (...) Ouch. You don't want to do that too much or you will torch (may have torched) your NiCds. NiCds do NOT like to be overcharged, it causes a problem called Voltage depression that many mistakenly call "memory effect". [snip] (...) Servos will (...) (25 years ago, 15-Mar-00, to lugnet.robotics.handyboard)
| | | | | Re: Overcharged battery?
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| no i disagree with this answer. the HB is designed to be left on normal charge indefinitely. the batts can get a little warm. if they are hot then something is wrong, but a little warm is nothing to worry about. when fully charged and with no load (...) (25 years ago, 15-Mar-00, to lugnet.robotics.handyboard)
| | | | | Re: Vector 2X driver
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| I just bought a Vector 2X electronic compass for a project. In looking at it the manual, I see that if the 2X is run in slave mode I can clock out data from it at my leisure using any digital pins available on the Handy Board. This could almost be (...) (25 years ago, 15-Mar-00, to lugnet.robotics.handyboard)
| | | | | Re: Overcharged battery?
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| (...) I was guessing here - most chargers don't check for peak charge, since I didn't know if the Handiboard charger did or didn't... If the charger has a trickle charge of more than C/50 or C/100 then NiCds will be damaged eventually on a long-term (...) (25 years ago, 15-Mar-00, to lugnet.robotics.handyboard)
| | | | | Re: Overcharged battery?
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| hi dennis, well, it's just a plain C/10 charge circuit. but i was under the impression that nicad's aren't damaged by that. it's possible i'm wrong :-). any other battery experts out there? fred In your message you said: (...) ly (...) ut (...) (25 years ago, 15-Mar-00, to lugnet.robotics.handyboard)
| | | | | Re: Overcharged battery?
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| (...) Hi Fred, I don't claim to be an expert on these, but what I have read leads me to believe that this may damage the cells if left on too long. For common NiCds (800mah AA' for instance) C/10 should really be considered a fast charge and not a (...) (25 years ago, 15-Mar-00, to lugnet.robotics.handyboard)
| | | | | Re: Overcharged battery?
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| (...) OK, this is good to know. (...) Yes, *if* more drop is necessary, more rectifier diodes would be called for (i.e. relatively fixed voltage drop), not a series resistor (v=iR). (...) I didn't have any 5watt resistors handy, so I put a pretty (...) (25 years ago, 15-Mar-00, to lugnet.robotics.handyboard)
| | | | | Re: Vector 2X driver
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| Yes, I run my Vector 2X is slave mode using only IC. I don't worry about missing the last bit since the precision of the heading is only +- 2 deg. It's very simple to code up. -Scott (...) (25 years ago, 16-Mar-00, to lugnet.robotics.handyboard)
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