Woodward 9907-173 LSM Load Sharing Module

The MicroNet Plus Expansion Chassis may use either single or redundant power supplies.

Each power supply module produces three regulated outputs: 

24 V @ 12 A (max), 5 V @ 32 A (max, derated above

55 degree C external ambient temperature), and 5 V Precharge @ 3 A (max).

A motherboard located on the back of the chassis provides the 

interconnection of the three outputs from each power supply module

into three corresponding power busses: 24 V bus, 5 V bus, and 5 V precharge bus.

The 24 V and 5 V busses are load shared between the two power supply modules.

The 5 V precharge bus is not load shared.

The part number 9907-232 LSM provides a 0.5-4.5 Vdc speed reference output to a speed control. 

Most Woodward speed controls use +/-3 Vdc for that reference,

which means it's likely used on another manufacturers speed control or ECU.

The output reference changes the speed reference in the speed control by providing 

a plus/minus offset from the speed controls normal reference.

Thus an output of 2.5 Vdc from the LSM would be a ZERO offset.

The speed pot on the LSM would provide a fixed offset from the normal 2.5 Vdc.

When the LSM is active with breaker closure [connection of terminal 13 to 14],

then the LSM seeks to equalize its generator percent of load with the average presented on the load share line.

The AGLC provides a ramping of the individual generator relative to the average on the load share line.

The LSM creates an offset up or down to match its percent loading to that of the generator average. 

When this is achieved, the LSM output should again be at it normal 2.5 Vdc.