Took Ridgid 4.0ah battery down to 18v. IT still read 3of 4 bars.
5 18650s in series at 18v, much closer to 50%, than 75% SOC.
Hooked cradle.to wattmeter, wattmeter to dc to dc 150 watt V booster, booster to 2nd wattmeter second wattmeter to 22ah agm. @ 12.99v.
Had set booster to 20.43v, then insert 18v battery into cradle.
Wattmeter went to over 200 watts then went to zero within a second.
Cradle shows green light.
Try wall wart as supply, same result.
Zero amp flow.
Green light happily shining solid.
Security torx bits to disassemble cradle.
DMM reads no continuity across circuit board fuse. I think it says 3.75 amps on endcaps
Make atc fuse holder from flag terminals, solder to circuit board fuse pads. Insert 5 amp fuse.
Test,, setting booster to just above battery voltage.
Whohoo.
Dial up booster voltage until it is accepting 60 to 70 watts. WaTtage falls ls as battery charges.
Spin dial back up, in stages, to keep 60ish watts flowing, not allowing over 20.43v.
So while i can eliminate inverter, and can charge at well over the 40 watts the wall wart can provide, i have to prevent huge voltage deltas to prevent too much amperage flow.
The ridgid cradle is obviously not designed to charge at 200 watts.
I dont know what it can safely handle, long term.
5 18650s in series at 18v, much closer to 50%, than 75% SOC.
Hooked cradle.to wattmeter, wattmeter to dc to dc 150 watt V booster, booster to 2nd wattmeter second wattmeter to 22ah agm. @ 12.99v.
Had set booster to 20.43v, then insert 18v battery into cradle.
Wattmeter went to over 200 watts then went to zero within a second.
Cradle shows green light.
Try wall wart as supply, same result.
Zero amp flow.
Green light happily shining solid.
Security torx bits to disassemble cradle.
DMM reads no continuity across circuit board fuse. I think it says 3.75 amps on endcaps
Make atc fuse holder from flag terminals, solder to circuit board fuse pads. Insert 5 amp fuse.
Test,, setting booster to just above battery voltage.
Whohoo.
Dial up booster voltage until it is accepting 60 to 70 watts. WaTtage falls ls as battery charges.
Spin dial back up, in stages, to keep 60ish watts flowing, not allowing over 20.43v.
So while i can eliminate inverter, and can charge at well over the 40 watts the wall wart can provide, i have to prevent huge voltage deltas to prevent too much amperage flow.
The ridgid cradle is obviously not designed to charge at 200 watts.
I dont know what it can safely handle, long term.
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