Woodward 505 Manual
Governor Woodward 505 calibration. 1. BLA POWER PVT.
LTD WOODWARD 505 GOVERNOR VALVE / ACTUATOR CALIBRATION &TEST LALIT SINGH Sr. Engineer C&I Dept. WHY CALIBRATION/STROKE CHECKING REQUIRED Before initial operation or after a turbine overhaul where any actuator or valve travel may have been affected, the below Valve Calibration procedure should be followed to insure that the 505 is correctly calibrated to the turbine control valve(s). When calibration is complete, 0 to 100% actuator position as displayed by the 505 must equal 0 to 100% actual valve travel.
BEFORE START PROCEDURE Before calibrating or testing, the unit must be tripped and the steam supply removed. This is to ensure that opening the control valve (s) will not allow steam into the turbine. Overspeed sensing and its relay are disabled during this process. Overspeeding the turbine may cause damage to turbine and can cause severe injury or death to personnel. STEAM TO THE TURBINE MUST BE SHUT OFF BY OTHER MEANS DURING THIS PROCESS. 505 KEY PAD AND DISPLAY. IN WOODWARD STEP-1 The 505’s Emergency shutdown contact input must be closed or jumpered throughout this procedure (All Turbine Trip Interlock From DCS Side will by pass after that setting jumper as mention below TB’s after that DCS will not be able to turbine trip).
JUMPERE DETAIL IN TSP PANEL Jumper J1:- In TSP Panel DIT-1 & DIT-2. Jumper J2:- In TSP Panel DIT-5 & DIT-6 Jumper J3:- In TSP Panel DIT-7 & DIT-8 Jumper J4:- In TSP Panel DIT-11 & DIT-12 Jumper J5:- In TSP Panel DIT-13 & DIT-14 Jumper J6:- In TSP Panel DIT-17 & DIT-18. IN WOODWARD STEP-2 Execute a system RESET command (Press the 505 “Reset” key) Press the 505’s front panel “Emergency Shutdown” button. Press the ‘ACT’ key then the SCROLL DOWN key until the “Stroke Actuators - Dsbled, Steam Must be Off” message appears. (Verify that the turbine’s steam supply has been shutoff before by an external Trip and Throttle valve.). IN WOODWARD STEP-3 Press the “YES” key (This will cause the screen to display a “Stroke to Min - Enabled, Min Curr Adjust.XX.XX” message).
Press the “YES” key to enable this mode or the “Scroll Down Arrow” to step to the mode desired. IN WOODWARD STEP-4 Stroke to Min - Enabld, Min Curr Adjust. XXX.XX — Press YES to force the actuator output to the minimum stop. The message will display ‘At Min’ and the actuator output current will move to its minimum setting.
The minimum current value can be adjusted only when the ‘at sign’ (@) is on the bottom line of the display. Press the SELECT key to move the @ symbol between the top and bottom lines. Press the ADJ UP or DOWN keys to change the 0% actuator current level.
Press the SCROLL DOWN ARROW to step the next desired mode, or the “CLEAR” key twice to save changes, and exit Calibration mode. IN WOODWARD STEP-5 Stroke to Max - Enabld, Max Curr Adjust. XXX.XX— Press YES to force the actuator output to the maximum stop.
Woodward 505 Manual 85017v1
The message will display ‘At Max’ and the actuator output current will move to its maximum setting. The maximum current value can be adjusted only when the ‘at sign’ (@) is on the bottom line of the display.
Press the SELECT key to move the @ symbol between the top and bottom lines. Press the ADJ UP or DOWN keys to change the 100% actuator current DOWN ARROW to step the next desired mode, or the “CLEAR” key twice to save changes and exit Calibration mode. IN WOODWARD STEP-6 Manually Adjust - Enabld, Stroke Valve XXX.XX — Press the ADJ UP, ADJ DOWN keys from this screen to move the valve’s output current between 0-100% at a 5%/second rate. This allows both the actuator and valve to be tested for binding, play, resolution, linearity, and repeatability. Press the “YES” key at any time to allow a setting to be directly ‘Entered’. The message will display ‘Manual’ when the ENTER mode is allowed.
When in the ‘Manual’ mode, press the “ENTER” key, enter the setting desired, then press the “ENTER” key again. This will step the actuator output to a specific position instantly. Press the “ADJ UP/DOWN” or “No” keys at any time to switch back to the “Enabld” mode. When calibration is complete, 0 to 100% valve position as displayed by the 505 must equal 0 to 100% actual valve travel. Press the SCROLL DOWN ARROW to step the next desired mode, or the “CLEAR” key twice to save changes and exit Calibration mode.
INFORMATION Press the CLEAR key twice to permanently save any minimum or maximum actuator settings into the 505. If variables are tuned or changed but not stored in EEPROM by pressing the CLEAR key twice, then those changes will be lost if power is removed from the control or if the control receives a CPU reset. FLOW CHART.
SCREEN DETAIL Screen 3 show only when the unit is shut down. Screen 4,5 and 6 show only when stroke actuator is set to yes. The asterisk (.) denotes a tunable parameter. To adjust this parameter, the “@” symbol must be on the display line containing the asterisk. The @ symbol is moved with the selection key. Note:- If change are made to min or max current values they can be recoded on the program mode worksheet under the “Driver Configuration” header. STROKE ACTUATOR MESSAGES MESSAGE MEANING Dsbld Stroke actuators function is disabled Enabld Stroke actuators function is enabled At Min Actuator output is set to the minimum value ( 0% ) At Max Actuator output is set to the maximum value ( 100% ) Manual Actuator output is in manual mode.
VOITH I/H CONVERTER OR CPC Voith electro hydraulic I/H converters adjust hydraulic positioning cylinders by means of a pilot valve. The positioning cylinders operate a valve that controls the mass flow needed to drive machinery. Voith I/H converters ensure very precise and highly dynamic control of the mass flow. I/H converters change a constant input pressure into a variable output pressure. A standard 0/4 – 20 mA with respect to 2- 4 Kg/Cm2 O/P Hydraulic Pressure. The major components of the I/H converter are a hydraulic unit and a force-controlled electromagnet.
WORKING PRINCIPAL A set signal w = 4.20 mA generates a magnetic force FMag in the VRM, the limits of which can be adjusted by means of the X0 and X1 potentiometers and which is then transmitted onto the control piston via tappet. The hydraulic force FHyd being proportional to the output signal pressure PA acts against this force. In the case of the two forces being equal, the control piston is positioned in the “hydraulic center” as shown in fig.
And the output signal pressure PA corresponds to the set signal. In the “hydraulic center“ position the control piston performs minimum oscillating movements in the area of the guiding edges P→PA and PA→T, in order to keep the output pressure PA on the value set by FMag. When increasing the set signal and thus FMag from this condition, the control piston position changes and thus connects the output pressure PA to the feed pressure P and blocks PA towards the tank return line T1and T2.
Now pressure PA will increase until the same has returned the control piston to the “hydraulic center“ and PA corresponds to the new set signal. The spring force FFed of the control spring generates a force-offset in order to guarantee the I/H converter function for output pressures of approx. FUNCTION Solenoid-force control generates a magnetic force of FMag in a 24V d.c. This magnetic force is proportional to the 0/4 – 20 mA input signal, the limits are configured using the X0 and X1 parameters.
The electronic control, magnetic flux measurement, engineering design of the magnet and the hydraulic pilot control together form a dynamic functional unit that is practically free of hysteresis. The control magnet applies the force FMag to the control piston. This in turn counteracts hydraulic force FHydr as generated by the pressure at output A over the cross-sectional area of the control piston. As a result of this regulation, the output line of the actuator always receives the exact required pressure and the oil quantity for positioning the steam or fuel valves. CALIBRATION Due to unintentional maladjustment of the parameters or changed operating conditions, new setting of one or both parameters may become necessary. We recommend to document adjustment of the parameters as well as the set values.
The parameters are adjusted by means of potentiometers X0 and X1. X0 - With help of potentiometer X0 the minimum output pressure PA min is adjusted at a set point of 4 mA. Pressure increase by turning the potentiometer clockwise. X1 - With help of potentiometer X1 the maximum output pressure PA max is adjusted at a set point of 20 mA. Pressure increase by turning the potentiometer clockwise. Note:-X1 should be adjusted before X0.
The X1- adjustment influences the adjustment of X0. I/P CURRENT V/S O/P PRESSURE S.No. (0-100% wrt 4- 20mA) O/P Press. 1 0 2 2 2 10 2.18 2.19 3 20 2.36 2.37 4 30 2.55 2.57 5 40 2.74 2.76 6 50 2.94 2.96 7 60 3.14 2.16 8 70 3.34 3.36 9 80 3.57 3.57 10 90 3.76 3.77 11 100 3.99 3.99.