JLG 680S, Service And Maintenance Manual

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SECTION 3 - CHASSIS & TURNTABLE
3121234 3-161
Troubleshooting
Table 3-11. Troubleshooting
Trouble Remedy
No generator output at platform AC receptacles. Be sure generator control switch is turned on at platform.
Check and secure electrical connections at platform, generator, and control box.
Be sure all equipment is turned off when starting unit.
Reset circuit breaker CB1.
Check plug PLG3 connection and/or connections at receptacles RC3 and RC5.
Be sure + 12 volts DC input voltage is being supplied to control box.
Check slip rings, wiring to brushes, and brush position on slip rings. Install new brushes if necessary.
Disconnect leads 12 and 13 from brushes, and check continuity across slip rings (nominal reading is 26 ohms). Replace generator if rotor is open.
Disconnect stator weld leads 1, 2, and 3 from circuit breaker CB1 , and check continuity between leads. Replace generator if necessary.
Disconnect plug PLG4 and check continuity between exciter leads 5 and 6. Replace generator if necessary.
Check power board PC1 and connections, and replace if necessary.
Check control board PC2 and connections, and replace if necessary.
Low generator output at platform AC recepta-
cles. Verify generator is running at 3600 rpm (60 Hz) or 3000 rpm (50 Hz).
Check slip rings, wiring to brushes, and brush position on slip rings. Install new brushes if necessary.
Disconnect leads 12 and 13 from brushes, and check continuity across slip rings nominal reading is 26 ohms). Replace generator if rotor is open.
Disconnect stator weld leads 1, 2, and 3 from circuit breaker CB1, and check continuity between leads. Replace generator if necessary.
Disconnect plug PLG4 and check continuity between exciter leads 5 and 6. Replace generator if necessary.
Check power board PC1 and connections, and replace if necessary.
Check control board PC2 and connections, and replace if necessary.
High generator output at platform AC recepta-
cles. Verify generator is running at 3600 rpm (60 Hz) or 3000 rpm (50 Hz).
Check slip rings, wiring to brushes, and brush position on slip rings. Install new brushes if necessary.
Check power board PC1 and connections, and replace if necessary.
Check control board PC2 and connections, and replace if necessary.
Erratic generator output at platform AC recepta-
cles. Check and secure electrical connections at platform, generator, and control box.
Verify generator is running at 3600 rpm (60 Hz) or 3000 rpm (50 Hz).
Check slip rings, wiring to brushes, and brush position on slip rings. Install new brushes necessary.
Disconnect leads 12 and 13 from brushes, and check continuity across slip rings nominal reading is 26 ohms). Replace generator if rotor is open.
Check power board PC1 and connections, and replace if necessary.
Check control board PC2 and connections, and replace if necessary.