The following is instructions and equipment/materials to make the Probe
Equipment:
Bass Rod
Red Lead
Green Lead
Black Wire
Red Wire
2,1000 ohms resistors
Red/Black Alligator Clips
100mm Plastic tube
Heat Shrink of 3 different sizes
Red & Black Rubber to convert the wires
Instructions
First we took the wire and stripped both ends
Then we soldered the resistor to the wire
We soldered the Red Lead to the wire
We then soldered the Green Lead to the wire
After that I granted the both end of brass and the middle
I soldered the Green & Red Lead together on brass
Use the black rubber to cover the brass and wire together and then I used the heat gun to to shrink the rubber so we can wrap it all together.
Reflection:
This lesson was good for me, it showed me the importance of Prob Lead testing for off short circuit in Electrical systems and also gave me new ideas on how it can be used.
BATTERY TESTING
This area talks about how to test & check a battery and if it is need for a service or if it needs replacement.
First is Visual Check
Checking if any unsafe or any terminal needs to be cleaned or replaced
Checking if any signs of swelling can cause over charging
Checking level of Acid or H2S04 if it is on the correct level
Testing specific gravity & the reading before you top up the Cells
You use hydrometer tester
Cell 1 = reading > 1125 = Red
Cell 2 = reading > 1275 = Green
Cell 3 = reading > NO READING
Cell 4 = reading > 1300 = Green
Cell 5 = reading > NO READING
Cell 6 = reading > 1300 > Clear
The battery Gravity failed, this means the battery needs to be replaced.
Testing a Open Circuit Tester
Removing Surface Charge
When the battery is fully charged, you will need to remove the surface charged and turn on the headlight or anything that draws power away from the alternator.
Use the volts meter to measure the results with 12.65v
100% > 12.7v
95% > 12.6v
75% > 12.5v
50% > 12.4v
25% > 12.2v
The measure of state of charged was 75% > 12.5v
The battery is always charged slowly or short fast bursts
To clean any surface on top the battery like acid or HzSo4
Use hot water and the baking soda to clean
Use vaseline to crease the terminals
To check if the battery needs to be recharged or replaced
The reading of recharged is = 50% > 12.4v
The reading of replacing the battery is = 25% > 12.2v
ALTERNATOR ON THE ENGINE TESTING AT SCHOOL
First Visual checking of the belt
See if the belt tension is Good
Check if Belt is cracked or needs replacement
Mounting of Alternator if not loose
Belt was worn out and needed replacement and was found to have no oil on the belt.
Using a voltmeter I measured the available voltage and these are my findings:
The Positive 12v Supply (B+) = 12 Volt
Terminal before the switch = 12 volt
Terminal after the switch = 12 volt
Terminal before the light bulb = 12.5 Volt
Terminal after the light bulb = 0 Volt
The negative on the 12v supply (N-) = 0 volt
While the voltage progressess through different components of the circuit you can clearly see that the voltage gets less as it gets used up pushing through the resistance.
VOLTAGE DROP Again I used the volmeter to measure the voltae drop across the different components of the circuit and my findings are below:
From the B+ of the 12v supply to the input of the switch = 0.07v
From the input of the switch to the output of the switch = 0.03v
From the output of the switch to the input of the bulb = 0.03v
From the input of the bulb to thye output of the bulb = 12.78v
From the output of the bulb to the N- of the 12v supply 0.1v
A voltage drop in an electrical circuit normally occurs when current is passed through the wire. The greater the resistance of the circuit, the higher the voltage drop. The largest voltage drop in my finding are from the input of the bulb to the output of the bulb, the reason for this is because when there is more voltage there is more resistance.
MEASURING AMPS IN A CIRCUIT Using a amp meter I measure the amps at different parts of the circuit, my findings are below:
Wire before the switch = 0.33 amp
Wire before light bult 1 = 0.33 amp
Wire between light bulb 1 & 2 = 0.33 amp
Wire between light bulb 2 & 3 = 0.33amp
Wire after light bulb 3 = 0.33 amp
The measurement on the circuit is showing the same reading because the same amount of amp is going through the circuit.