Page 21 - 810 Trianing Book Extract

B More complex machine setups

Simple machines include one motor, one transmission (coupling, belt, gearbox), and one driven unit (pump, fan,
compressor, blower, spindle, other). This makes diagnosis of the entire machine train relatively straight forward.
Complex machine trains have more than one motor, transmission, or driven unit. In order for the automated

diagnostic program to cover multiple machine trains, the user should split the machine train into two simple
machines—each with one motor, one transmission, and one driven unit.

This will produce two diagnostic reports that overlap. Review each report together and then make repair
decisions.

Example 1: Dual hydraulic pumps

Motor connected to two driven shafts, on both ends of the motor.

Each pump shaft has multiple pump impellers therefore split machine train into two separate machines.

Hydraulic Pump 101 Left Hydraulic Pump 101 Right

Skip motor bearing 1, and measure on the bearings 2, 3, and 4. No need to measure both motor bearings twice.
Then do the same thing on the right side.

The tests will provide two reports. Review the reports for faults for the entire machine train:

• Motor from bearing 2 (overlap from report 1 and report 2)

• Pump 1 from bearing 3 (left pump from report 1, right pump on report 2)

• Pump 2 from bearing 4 (left pump from report 1, right pump on report 2)

The user will usually overhaul all pumps on both sides if one is bad enough to take the machine off line.
No need to be overly critical about where to measure. Just ind a nice lat spot on solid metal close to a bearing.

Chapter 6: Advanced topics 139