AA VIGILANCE CONTROL TROUBLESHOOTING
Contents
1. a Brakes released and indicator hand in green band PROBABLE CAUSE whistle faulty Defective piping to audible warning Audible Warning Valve D 70 No 8 defective Choke C blocked or DC 25 Audible warning valve No 9 defective Audible warning valves D 70 No 8 or DC 25 No 9 not seating correctly Allow indicator to enter red band and note blow of air at whistle Allow indicator to enter red band loosen connection on top of vigilance unit casting and note blow of air tighten connection and test audible warning piping Allow indicator to enter red band to high range loosen connection on top of vigilance unit casting and if no blow is present D 70 valve No 8 defective Allow indicator to enter red band in low range loosen connection on top of vigilance unit casting and if no blow present remove DC 25 No 9 audible warning valve and examine choke if clear DC 25 is defective Change DC 25 audible warning valve No 9 if none available in store change with the brake pipe reset valve No 15 If trouble still exists D 70 valve No 8 is defective If trouble is rectified the D 25 valve now on the brake pipe reset will have a blow of air at the exhaust port and it should be changed Change whistle Repair pipework Change D 70 valve Clear choke or change DC 25 valve Change defective valve Part 10 Section 1 35 SYMP2. pipe pressure and note there is an exhaust from the brake pipe reset valve No 15 if so the snap action penalty valve is defectiv If no blow from exhaust of brake pipe reset valve with brake pip this valve is defectiv reduced below 25 psi Fully apply independent brake and test with soap locking volume piping from C 13 check valves No 11 and 12 to snap acting penalty valve No 13 and brake pipe reset valve No 15 not forgetting the exhaust port of this valve brake pressure normal Also check exhaust port at fitting between check valve No 11 and unit casting Test as above and at leakage exhaust port of snap action penalty valve Check valve C 13 No 12 not seating correctly Reduc pressure of DC 17 penalty application valve timing volume pressure to operating then rises is defectiv No 10 if timing volume pressur and falls about 2 psi check valv REMEDY Clean valve and examine 1 16 by pass port in Emergency Application Valve Change snap action penalty valve Change DC 25 brake pipe reset valve Repair piping or clean check valve Change snap action penalty valve Clean rubber valve or renew if badly marked Part 10 Section 1 35 6 SYMPTOM Audible Warning Unobtainable Gauge Registered Correctly a High and low timing pressure Audible Warning Continually Blowing
3. AA VIGILANCE CONTROL TROUBLESHOOTING The following is a list of some of the faults that could occur in the Vigilance Control System SYMP TOM 1 Penalty Application With Audible Warning a Indicator hand in green band at time of application b High timing volume pressure Cc Low timing volume pressure Audible warning on trailing d Trailing Unit unit Note Trouble experienced whilst a trailing unit Drawing Reference PL 11 PROBABLE CAUSE Faulty Indicator Magnet valve No 3 permanently energised or not exhausting Magnet valve No 3 energising not Suppression valve DC 25 No 2 seating not or Double check valve type BC No 6 sticking or piping defective Part 10 Section 1 35 Operate Vigilance throughout its range noting operating pressures of the various valves and that the gaug Check gauge against brake cylinder gauge pressures stable should register 3 4 psi approx less than brake cylinder pressure Brake cylinder gauge should be tested against Standard test gauge movement is free Check for blow of air from magnet valve exhaust port if no blow turn off isolating switch to acknowledgment button if blow is then present the trouble is electrical REMEDY If defective change gauge allowable gauge error 2psi Hand of gauge may be set if less than 5 psi in error
4. Electrician to locate and rectify defect Electrician to Make sure all switches in magnet valve circuit are correctly positioned Depress magnet valve by hand note if pressure rises and that equipment functions correctly whilst magnet valve is manually operated Make a full independent brake application and magnet valve No 3 If timing volume increases continuously suppression No 2 is not seating nergis pressur valve DC 25 Release brakes close isolating cocks to both driver s brake valve pedestals disconnect pipe No 6 check valve may be sticking or there is a piping defect Test piping from drivers brake valve isolating cocks to the double check valve No 6 from centre of double check valve if no blow is present locate and rectify defect Change DC 25 suppression valve No 2 Clean double check valve No 6 or repair piping Part 10 Section 1 35 SYMPTOM 2 Penalty Application Without Audible Warning a High timing volume pressure Indepen dent brake applied b Indicator hand in green band PROBABLE CAUSE Independent brake application pressure too high Penalty valve DC 17 No 10 not seating correctly Observe brake cylinder pressure feeds this pressur Reduc into timing vol in the vigilance if it becomes ume operating the valves xcessiv Pressure re
5. TOM 6 Audible Warning Continually Blowing b with independent brake applied PROBABLE CAUSE Independent Brake pressure too low isolating cock closed or piping 7 Brake Cylinder Pressure Bogie brake Not Suppressing Equip ment defective 8 Timing volume pressure a Falls rapidly when brakes released magnet valve de energised b Slow in charging or will not charge C 13 check valve No 5 defectiv A full 45 psi 25 psi No 2 cylinder pressur independent brake application should be in the brake cylinders if this is below it will not seat the suppression valve allowing the whistle to sound If brake is below 17 psi a penalty occur application will Observe brake cylinder gauge for the bogie under the No 1 cab registered bogie isolation cock is closed defective if no pressur or piping Make a full independent brake application and release noting that timing volume pressure AA System Check valve in check valve choke No 24 defectiv drops with brake cylinder pressure Energise magnet valve and note exhaust from same exhaust will be excessive if check valve defectiv Piping defective pipe leakage test Charge timing volume to 65 psi or as high as possible then apply independent brake and with magnet valv nergised note leakag Rectify defect in brake equipment Open isolation co
6. ck or repair piping Clean rubber valve renew if badly marked Clean rubber valve renew if valve badly marked Repair pipework or clean rubber valve
7. ducing val defective with A7 equipment lve may be set too high or or the self lapping portion of the B7 independent brake set too high or defective Check for blow of air from 1 16 port at connection of C 13 check valve to vigilance valve unit casting full stop if DC 17 No 10 Penalty applications whilst equipment is suppressed either by 25 psi brake cylinder pressure or by both driver s brake valve closed independent brake application blow dia relief No 11 If blow make a will valve is leaking through should not take place over isolating cocks being If they do test for Symptom 1 d pressur change M3 pressure reducing valve or change B7 independent brake valve Change DC 17 valve Part 10 Section 1 35 SYMP TOM Penalty Application Cannot Be Released Penalty Application Resets Without the Brake Pipe reduced below 25 psi PROBABLE CAUSE Emergency Application Valve No 16 off its seat OR Snap Action Penalty Valve No 13 defective OR Brake pipe reset valve defective Locking volume leakage Snap Action Penalty Valve No 13 defective TEST Blow of air at Emergency Application Valve C No 16 exhaust will be evident lean emergency application valve if trouble still persists check for blow at the exhaust of Snap Action Penalty Valve No 13 If a blow reduce brake
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