A plug is called a device for checking the state of charge of individual battery cells. This plug consists of a powerful pull-up resistor, a DC voltmeter and two test leads.
Instructions
Step 1
Find out what the voltage should be on a fully charged single battery bank from its instruction manual. Also make sure the battery is designed to allow access to the individual banks.
Step 2
Take a micrometer. In series with it, include a resistor of such a resistance that at a voltage slightly exceeding the limit for one can. Replace the scale of the instrument with a new one. Calibrate it by applying a varying DC voltage in the correct polarity to the resulting voltmeter. Monitor the voltage supplied during the calibration with a reference voltmeter.
Step 3
Find out from the instructions for the battery the value of the rated (not maximum!) Load current. Convert all values to the SI system, and the result will be in it. Calculate the resistance of the load resistor using the formula R = U / I, where R is the resistance, Ohm, U is the voltage, V, I is the current, A. Be careful: substitute the voltage of one cell in the formula, not the entire battery.
Calculate the power allocated to the resistor by the formula: P = UI, where P is the power, W, U is the voltage, V, I is the current, A. Select the nominal power of the load resistor more than that allocated from the standard series. It must be wired.
Step 4
Get a test lead that can handle the current flowing through the pull-up resistor. Connect them to the resistor with wires also capable of withstanding this current. Solder the joints well.
Step 5
Connect a voltmeter, consisting of a microammeter and a small resistor in series with it, in parallel with the load. On the probes, indicate the polarity corresponding to the polarity of the voltmeter. Then insulate the joints.
Step 6
Attach all parts to a rigid dielectric and fireproof frame fitted with a handle. Position the probes so that the distance between them is equal to the distance between the jar terminals.
Step 7
Be sure to make sure that the battery is not currently being charged, and that no other batteries are being charged near it. If charging of the tested battery or neighboring batteries has recently ended, ventilate the area so that there is no hydrogen in the air before using the load plug.
Step 8
Connect the load plug to the banks one by one, observing the polarity. Keep it connected to the bank for a few seconds, make sure that the readings do not change during this time. Do not keep the plug connected any longer. Read the readings immediately before disconnecting the device from the can.
