Use an online ohm calculator you need
18 volts @ 500 milliamperes or
25 volts @ 500 milliamperes the resistor value will a little bit higher
Use at least 2 watt resistor for this device at a minimum
If you use this method above do not leave the battery on the charger continuously this will shorted the life of the batteries
However you would be better off if you used something like a LM317 voltage regulator in current mode this will give you better current control which can also be found on how to use it in current mode in the data sheet for this device
If you use a voltage regulator in current mode I would recommend that you use 50 milliamperes and 500 milliamperes if you want to leave the battery on the charger all the time use the 50 milliamperes mode and if you want a faster mode charging mode use 500 or 750 milliamperes just make sure that you switch it back to the lower current mode after charging if you leave it on charger
9 PC LCD Monitor
6 LCD Flat Screen TV
30 Desk Top Switching Power Supply
10 Battery Charger Switching Power Supply for Power Tool
6 18v Lithium Battery Power Boards for Tool Battery Packs
1 XBox 360 Switching Power Supply and M Board
25 Servo Drives 220/460 3 Phase
6 De-soldering Station Switching Power Supply 1 Power Supply
1 Dell Mother Board
15 Computer Power Supply
1 HP Printer Supply & Control Board * lighting finished it *
These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%
1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
2 Hem Saw Computer Stack Board
All of these had CAPs POOF
All of the mosfet that are taken out by bad caps
One note about these battery charger do not get the idea that you can put a led on the charging board remove all components from the device board and use jumper wires because if you do not do this the charger will not work correctly I have tried this before and the results were that the charger keeps charging the battery instead of lowering the current when fully charged or refuse to charge the batteries
If this person is building from ground up and designing this charger to charge nicad batteries the same thing will hold true do not add a led at the battery pack you would have the same exact results
9 PC LCD Monitor
6 LCD Flat Screen TV
30 Desk Top Switching Power Supply
10 Battery Charger Switching Power Supply for Power Tool
6 18v Lithium Battery Power Boards for Tool Battery Packs
1 XBox 360 Switching Power Supply and M Board
25 Servo Drives 220/460 3 Phase
6 De-soldering Station Switching Power Supply 1 Power Supply
1 Dell Mother Board
15 Computer Power Supply
1 HP Printer Supply & Control Board * lighting finished it *
These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%
1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
2 Hem Saw Computer Stack Board
All of these had CAPs POOF
All of the mosfet that are taken out by bad caps
9 PC LCD Monitor
6 LCD Flat Screen TV
30 Desk Top Switching Power Supply
10 Battery Charger Switching Power Supply for Power Tool
6 18v Lithium Battery Power Boards for Tool Battery Packs
1 XBox 360 Switching Power Supply and M Board
25 Servo Drives 220/460 3 Phase
6 De-soldering Station Switching Power Supply 1 Power Supply
1 Dell Mother Board
15 Computer Power Supply
1 HP Printer Supply & Control Board * lighting finished it *
These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%
1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
2 Hem Saw Computer Stack Board
All of these had CAPs POOF
All of the mosfet that are taken out by bad caps
My diagram is of a Jobmate Ni-Cd charger
Board # KW14-V0
R1's outside coating has burned away,leaving no color code bands
In circuit R1 measures 3.9 ohms
My diagram is of a Jobmate Ni-Cd charger
Board # KW14-V0
R1's outside coating has burned away,leaving no color code bands
In circuit R1 measures 3.9 ohms
Are these formulas correct
VR1=1.17 x Battery Voltage + 3.3v
R1 = 3.3 / (1/4 of Battery Voltage)
Thanks to everyone for your information.
Okay
Like what was mentioned earlier in this post if just replace the resistor the same exact thing will happen again because this is the cheapest way to charge a battery which has all kinds of issues
9 PC LCD Monitor
6 LCD Flat Screen TV
30 Desk Top Switching Power Supply
10 Battery Charger Switching Power Supply for Power Tool
6 18v Lithium Battery Power Boards for Tool Battery Packs
1 XBox 360 Switching Power Supply and M Board
25 Servo Drives 220/460 3 Phase
6 De-soldering Station Switching Power Supply 1 Power Supply
1 Dell Mother Board
15 Computer Power Supply
1 HP Printer Supply & Control Board * lighting finished it *
These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%
1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
2 Hem Saw Computer Stack Board
All of these had CAPs POOF
All of the mosfet that are taken out by bad caps
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