HUB 7N8827 - Caterpillar

The chart lists the serial number break between the earlier fault parameters and current fault parameters. All digital voltage regulator part numbers starting with 116 (116-XXXX) and some of the regulator part numbers starting with 130 (130-XXXX) use the earlier alarm/fault handling procedures. The current fault parameters/procedure is implemented on all versions of the digital voltage regulator built after March 1996. Another method to determine if a digital voltage regulator uses the current alarm/fault handling procedures is to check the PROM ID (parameter :91). A value of 1.03 or greater indicates use of the current alarm/fault parameters/procedures.
Table 1
Earlier Fault Parameter
Serial Number Break    
Regulator
Part Number     Earlier Fault Parameter
Serial Number    
130-3471     LBNBA0001-0123    
130-3472     LBNBB0001-0301    
130-3473     LBNBC0001-0176    
130-3474     LBNBD0001-0190    
130-3475     LBNBE0001-0392    
130-3476     LBNBF0001-0238    
116-XXXX     All    Fault Identification (For Earlier Digital Voltage Regulator)
Check the excitation.
Use a multimeter across the exciter field outputs F1 and F2. A multimeter should be set for VDC. Another way to verify that the regulator is providing excitation to the generator is by looking at parameter :55. Parameter :55 describes excitation current.Expected Result: The digital voltage regulator is providing the excitation to the generator.Results:
OK: Go to Step 2.
NOT OK: Go to Step 4.
Check the status of the alarm.
Check the display on the digital voltage regulator.
Check the status of the alarm output.Expected Result: The display on the regulator is flashing or the alarm output is off (open circuit). When alarm output is off, an alarm is active.Results:
OK: Go to Testing And Adjusting, "Fault Handling For Earlier Digital Voltage Regulator", section Alarm Clearing (For Earlier Digital Voltage Regulator).
NOT OK: Go to Step 3.
Check the alarm fault log.
Check the status of the alarm fault log. The alarm fault log is described by parameter :95.Expected Result: The alarm fault log shows "0000".Results:
OK: The alarm fault log shows "0000". No new alarm has occurred. STOP.
NOT OK: Go to Testing And Adjusting, "Fault Handling For Earlier Digital Voltage Regulator", section Alarm Clearing (For Earlier Digital Voltage Regulator).
Check the status of the fault.
Check the display on the digital voltage regulator.
Check the status of the fault output.Expected Result: The display on the regulator is flashing or the fault output is off (open circuit). When fault output is off, a fault is active.Results:
OK: A shutdown fault has occurred and is active. No new faults will be detected until active shutdown fault is reset. Go to Step 5.
NOT OK: Go to Testing And Adjusting, "Troubleshooting".
Check the shutdown fault log.
Check the number logged in the shutdown fault log. The shutdown fault log is described by parameter :92. Check the flashing number on the display.Expected Result: The number starts with a 7 (7xx).Results:
OK: The number starts with a 7 (7xx). A resettable fault has occurred. It can be reset without removing power by activating either shutdown fault reset, parameter :96 or the external fault reset switch. The fault can also be reset by cycling the power to 24 VDC power inputs ("B+"/"B-").