Wacker Neuson G 2.1A Repair Manual

Wacker Neuson G 2.1A Repair Manual Manual pdf 35 page image

5A-950 HZ PORTABLE GENERATORS G3.3A/G4.6A/GS4.6A/GS5.7A 5ARestoring Residual Magnetism to the Brush Type GeneratorsDisconnect leads F1 and F2 from the brush holder (a). Run the generator at its normal speed and apply 12 volts froma battery to the brush holder for approximately 3 seconds. Ensure the positive lead is applied to the brush holder nearestthe bearing housing. The output voltage of the generator, with the 12 volt supply connected, should be approximatelynormal voltage. See Figure 5-12.Stop the generator and reconnect leads F1 – F2.CAUTION: Ensure the battery leads are connected to the brush holder with the correct polarity, and leads F1 – F2are isolated from each other and earth. Loss of residual magnetism will result if leads touch ground, each other, or wrongpolarity.5.12 Testing the Bridge RectifierAccessing the Bridge Rectifier1. Remove the generator cover.2. Remove leads Z2 and Z3 from the bridge rectifier (b),and leads F1 and F2 that go to the brush assembly.Checking Bridge RectifierTo check the rectifier, follow these steps:1. Set multi-meter on R x 1000 range.2. Remove all wires connected to the rectifier.3. Place the meter probes on two adjacent rectifierterminals and check resistance value. See Figure5-13.4. Reverse the probes and recheck.5. The meter should indicate low resistance in onedirection and a high resistance in the other direction.6. Repeat this procedure for each adjacent set of termi-nals on the rectifier until all four diodes have beenchecked.Figure 5-12. Diode BridgeZ2F2Z3F1F2F1Z3 Z21023SD52Figure 5-13. Checking Diode Bridge1023SD985.13 Testing the ChokeTo test the choke remove wires Z1 and Z3 from thechoke (c) and the choke assembly. The resistancevalue of the choke should be 7.5 ohms.