DIMM board battery questions answered.

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OldFoo

Post by OldFoo »

the most strange thing done by this french guy, is that the battery he put in his dimm has two connectors. one to use it and one to recharge it. but he only plug the "use connector" so i wonder how the battery will recharge.

I just asked him on the french forum and will tell you then.



edit:

he didn't try to make the battery work like the original.

to recharge he will unplug the use connector and plug the recharge connector to a battery charger...
OldFoo

Post by OldFoo »

So I finally ordered a battery, switched the pcb and... it won't charge. I'm not sure why.



Possible Issues:



The battery pack I ordered only had the blue wire (marked BC on the pcb) hooked up to the positive terminal of one battery, while the Sega pack had it connected to the positive of one battery and the negative of the other. So I went ahead and connected it to both.



The pack I ordered has a polystrip attached, while it doesn't seem that Sega version did. Maybe this is affecting it?



I suppose I could have accidentally shorted out the battery while working on it, but I'm not sure how to tell if it is actually working at all.



Also, the label on the battery says the following:
  • 'The battery pack must be charged with powerizer smart charger and select 8.4V on the charger. Max. discharging current must be less that 4A. Keep the battery from fire and impact.'
Any suggestions?
OldFoo

Post by OldFoo »

If you shorted the batteries, you would know because they would get hot. Maybe even leak. What you should do is re-create the same terminal hookup as the original and see if it charges. If it doesn't, then you know the batteries are no good anymore.



An alternative would be put your meter to the batteries and see if you get over 1 volt. If you get below, or zero, then they're dead.



Don't worry about their disclaimer. They just want you to buy their stuff to charge the batteries.
OldFoo

Post by OldFoo »

I did recreate the same connections as the original Sega battery, if that's what you mean. It's a brand new battery pack too. Of course, I just went to test it with my multimeter and the meter's dead. Stupid Radio Shack piece of shite! :smt011 :smt097 Hey Josh, you wanna make me up one of these bad boys? My patience is wearing thin.



By the way, I mentioned the warning message because of the 4A part--I know polyswitches are meant to limited the discharge rate, so if the DIMM board needs more than 4A maybe that's why it's not working?
OldFoo

Post by OldFoo »

They are saying that you shouldn't pass 4 amps at once. If you think about it, that's alot of energy to discharge and would only last a few seconds on a full charge. Nobody, in their right mind, would attempt this as using more batteries would be a better solution. The Naomi doesn't use nearly that much. I haven't gone as far as calculating how much it uses, but I'd imagine that it uses no more than 100mA. That's .01 amps.



About making you one, it's possible. But I would need to gut a dead battery and I don't have one. :smt009 If I come across one, I'll let you know.
OldFoo

Post by OldFoo »

I could send you the remains of mine if that would help--I'd just unsolder it from the battery pack and mail it to you. Let me know.
OldFoo

Post by OldFoo »

By the way, do you know what the red and green LEDs on the DIMM board represent? They are visible from the battery compartment when the cover is off and only light up if the battery is connected.
OldFoo

Post by OldFoo »

From what I can tell, they are status LEDs. I gather that they show when charging, discharging and any errors present like 'cannot charge' or something like that. Since there is no documentation, it's hard to tell which lights tell what and when.
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