UENR0623-02 89 Electrical System e. The current is below 0.015 amperes. The alternator is operating correctly. There is an electrical load on the machine. Go to step 8. Never disconnect any charging unit circuit or bat- tery circuit cable from the battery when the charg- ing unit is operated. A spark can cause an explosion from the flammable vapor mixture of hydrogen and oxygen that is released from the electrolyte through the battery outlets. Injury to personnel can be the result. f. The current is above 0.015 amperes. There is an internal fault with the alternator. Replace the alternator. Refer to Disassembly and Assembly, “Alternator - Remove and Install” for the correct procedure. 8.
Turn off all electrical accessories. Turn the keyswitch to the OFF position. The battery circuit is an electrical load on the charging unit. The load is variable because of the condition of the charge in the battery. a. Connect a current probe or an ammeter to a digital multimeter. Ensure that the probe is zeroed. Clamp the current probe or an ammeter to the main ground cable. Clamp the tool with the positive side away from the battery. NOTICE The charging unit will be damaged if the connections between the battery and the charging unit are broken while the battery is being charged. Damage occurs because the load from the battery is lost and because there is an increase in charging voltage.
High voltage will damage the charging unit, the regulator, and oth- er electrical components. b. Monitor the current and remove the fuses and circuit breakers one at a time. Check the current after each fuses or each of the circuit breakers are removed. After removing a fuse and checking the current, replace the fuse. Start with the main fuses and proceed to the smaller circuits. The correct procedures to test the battery can be found in the manual that is supplied by the OEM. c. If removing a fuse causes a current drop, then the problem is within that circuit. i06260318 Charging System - Test d. Check if any components on the circuit are on. e.
If all components are switched off, disconnect electrical components on that circuit one at a time and monitor the current. The condition of charge in the battery at each regular inspection will show if the charging system is operating correctly. An adjustment is necessary when the battery is constantly in a low condition of charge or a large amount of water is needed. A large amount of water would be more than 28 mL (1 oz) per cell per week or per every 100 service hours. There are no adjustments on maintenance free batteries. f. After all components on the circuit have been disconnected, check the current. If the problem still exists, check the wiring for corrosion.
Check if there is a short to ground. Note: The standard current is 0.05 amperes. A current value above this figure usually indicates a problem. However, some large machines with multiple control modules have a higher acceptable limit. When it is possible, make a test of the charging unit and voltage regulator on the engine, and use wiring and components that are a permanent part of the system. Off-engine testing or bench testing will give a test of the charging unit and voltage regulator operation. This testing will give an indication of needed repair. After repairs are made, perform a test in order to prove that the units have been repaired to the original condition of operation.
i01899136 Battery - Test Alternator The charging rate of the alternator should be checked when an alternator is charging the battery too much or not charging the battery enough. Most of the tests of the electrical system can be done on the engine. The wiring insulation must be in good condition. The wire and cable connections must be clean, and both components must be tight.