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Manual 35018V1
505XT Digital Control System for Steam Turbines
Woodward
213
Addr Description
Units Multiplier
3:0241
Trips with Load >25% Counter
1
3:0242
Trips with Load >75% Counter
1
3:0243
Total Run Time Hours Counter
hrs 1
3:0244
Run Time Hours with Load >25% Counter
hrs 1
3:0245
Run Time Hours with Load >75% Counter
hrs 1
3:0246
Peak Speed Reached
rpm 1
3:0247
Maximum Acceleration Reached
rpm 1
3:0248
Number of Overspeed Trips
1
3:0249
LP Valve Limiter x100
% 1
Table 6-10. Analog Write Addresses
Addr Description
Units Multiplier
4:0001
Modbus Entered Speed Setpoint rpm
none
4:0002
Modbus Entered Casc Setpoint
Casc units
Casc scale factor
4:0003
Modbus Entered Aux Setpoint
Aux units
Aux scale factor
4:0004
Modbus Entered Extraction
Setpoint
Ext/Adm units Ext/Adm scale factor
4:0005
Modbus Droop demand
%
x0.01
4:0006
Modbus Entered Inlet Setpoint
Inlet Units
Inlet scale factor
4:0007
Modbus Entered Exhaust Setpoint Exhaust Units Exhaust scale factor
4:0008 SPARE
Last Turbine Trip Cause
The cause of the last turbine trip (address 3:0086) is an integer that represents the Event ID found in
Table 5-2.
505XT Controlling Parameters
The controlling status parameter messages that appear on the display of the 505 are sent over the
Modbus links. Customers implementing new interfaces, or those with the ability to change their operator
interface should use the new addresses shown. These addresses will have messaging in a straight
forward order and will contain the complete list of all messages available.
Logic was designed into the 505XT to support ‘legacy’ messaging so that customers replacing old 505’s
would not be required to change the Master Modbus gathering this data. This will work, but those
interfaces will not receive messages related to new features in the 505XT, it is a subset of the information
available on the new addresses.
Table 6-11. Control Status Message Addresses
Message New
address
(full
info)
Legacy address
(limited)
Control Status
(3:0234)
Ratio Limiter Status
(3:0235)
Map Limiter Messages
(3:0236)
505 Control Parameter
(3:0001)
505E Control Parameter 1
(3:0070)
505E Control Parameter 2
(3:0071)
The controlling parameter status of the 505XT uses an Analog Read register (3:0001) to identify the
parameters that are in control. This variable follows what is displayed on the controlling parameter
screen, under the ‘CONT’ key. The variable gives the current status of the control and is defined in the
following table.