McGrath medical battery replacement?

D McG

Joined Apr 12, 2020
4
Hello,
I am also a biomedical technician. I followed the procedure without problem. The lighting works well, but the Mc Grath screen does not turn on.
Does anyone have the same problem ?
I'm using a 3.6V rechargeable lithium battery.
Thank you
This sounds like what happens when the original batteries finally are exhausted. I pretty consistently can get an additional 200 minutes of use out of the original battery before the screen stops working (yet the laryngoscope light continues to work). The battery still shows >3.6 volts. I hypothesize that it is unable to maintain voltage under the load of the device in it's on state. Perhaps something similar is happening with your battery.
 

D McG

Joined Apr 12, 2020
4
Battery inside is ER14505M - cylindrical, non-rechargeable 2 Ah LiSOCI2 cell. Fortunately it's relatively cheap (6-8 USD). Type size and something like LOT number is imprinted on the plastic battery case.

May be block 0x00 is just a LOT number (doesn't changes over time) and it's enough to overwrite 0x01 block with 0x00000000 to reset timer? May be there some magic combination which disables timer for a given battery at all?
Thank you, JohnyD. Good to know that I am barking up the wrong tree in terms of recharging being futile.

For consideration, finding a "magic code" to disable the timer may not be ideal in terms of unpredictable failure. I am trying to gather enough data to reliably reprogram the timer for simple reuse of the original battery with a realistic operational life expectancy (so far 199 - 214 minutes with an N of 3 batteries).
 
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