Service Bulletin No. 2930

Transcription

1 Service Bulletin No MODEL TYPE SECTION/GROUP DATE E / J Series Coaches Service Information 8--Engine Mar. 30, 2006 SUBJECT AMEREX FIRE SUPPRESSION SYSTEM CONDITIONS Service Information Only Description: Effective with unit number 63495, MCI began installing the provision for the Amerex fire suppression system on E and J model coaches. The AMEREX fire suppression system is a completely automatic system which continuously monitors the engine compartment for any fire hazards. The system utilizes strategically located thermostats which are connected to an electronic control panel module. The control module features an engine shutdown circuit to minimize the fire hazard. This suppression system utilizes an electronic triggering device for release of the dry chemical compound ( ABC ) extinguishing agent. Attached to this bulletin are Supplement pages for the AMEREX fire suppression system, that can be inserted into the MCI E4500 / J4500. Printed in Canada

2 Date December 2005 Page 8D-1 E4500 & J4500 Series SECTION 8D AMEREX FIRE SUPPRESSION SYSTEM CONTENTS OF THIS SECTION SUBJECT PAGE General Description... 8D-2 Components... 8D-2 Operation... 8D-2 Maintenance... 8D-4 Specifications... 8D-5 Resettable Fire Alarm Sensors... 8D-6 General Description... 8D-6 Maintenance... 8D-6 Specifications... 8D-7

3 E4500 & J4500 Series Date December 2005 Page 8D-2 GENERAL DESCRIPTION The AMEREX fire suppression system is a completely automatic system which continuously monitors the engine compartment for any fire hazards. The system utilizes strategically located thermostats which are connected to an electronic control panel module. The control module features an engine shutdown circuit to minimize the fire hazard. This suppression system utilizes an electronic triggering device for release of the dry chemical compound (ABC) extinguishing agent. COMPONENTS The suppression system installation is made up of several major components, which are mounted at various locations throughout the coach. Control Module The control module is responsible for auto function and fault detection of the system. The control module is mounted on the driver s side A-post, and incorporates both audible and visual alarms to warn of any hazard. System status is displayed with red and green LEDs in conjunction with the audible alarm. This unit is wired directly to the batteries for continuous duty and interconnects with the thermostats and manual actuator. Thermostats Three normally-open thermostats are mounted inside the engine compartment to monitor temperature heat levels. The high temperature trigger thermostat (350_F) is located directly over the engine turbocharger assembly. There are two low temperature thermostats [280_F (138_C)]. One is located on the rear cross seat in front of engine over the AC compressor and alternator. The other is located on the crossmember to the right of the engine over the exhaust manifold. The sensors are connected directly to the control panel module. The 350_F (177_C) sensor is required in the high temperature area above the turbo to prevent an inadvertent discharge. Manual Actuator The manual actuator switch is mounted to the left of the driver on the console. with easy access to the ring pin and FIRE button. To activate the switch, the operator must pull the safety ring pin, breaking the plastic lockwire seal, and press the red FIRE button. This action signals the electronic control module, which sounds the audible alarm, discharges the agent cylinder and shuts down the engine (15 seconds). Chemical Cylinder A 25 pound pressurized chemical cylinder is mounted in a special bracket and located in the #3 LH baggage compartment. This tank is fitted with a discharge valve and electronic control head assembly. The release valve is connected by hose to a central distribution block. OPERATION When the thermostats mounted in the engine compartment sense a fire, a signal is sent to the control head on the agent cylinder. The system can also be manually activated by pressing the manual actuation button in the driver s area. The electric actuator opens the discharge valve on the agent cylinder, allowing the pressurized dry chemical to flow through the distribution holes and through the four spray nozzles located in the engine compartment, extinguishing the fire. CONTROL PANEL MODULE Normal Operation During normal operations, a green System OK LED is illuminated on the front of the control panel to indicate that all circuits are intact and functioning properly. Fire Condition When either of the normally-open thermostats heat up to their preset temperature, their contacts close and actuate a ground to energize the panel alarm mode circuit. During hazard conditions, the control panel s green SYSTEM OK LED goes out and a red FIRE LED illuminates. Simultaneously, the control panel s engine shutdown timer begins its countdown, and energizes the control head on the agent cylinder valve. The audible buzzer continually sounds during hazard events (see Figure 1). This alarm will continue to operate until the PUSH TO SILENCE button on the control panel is actuated. When the silence button has been pushed, a SILENCE ENGAGED LED is illuminated. The alarm must sound before the silence button becomes operational. The alarm cannot be set to silence prior to a fire or a fault condition.

4 Date December 2005 Page 8D-3 E4500 & J4500 Series NOTE: As a safety provision, the engine shutdown RELAY RESET button may be activated at any time before the countdown time reaches zero. This resets the time to its original pre--set time. This may be done as many times as necessary to safely bring the coach to a controlled stop. When the timer reaches zero, the RELAY RESET switch shuts the engine down, and the RELAY ENGAGED LED remains on. Figure 1. Control Panel When the fire is extinguished and the thermostat cools, its contacts reopen. The red LEDs remain illuminated until the system is serviced and the control panel is reset. Fault Condition If a fault condition occurs in the electrical actuator circuit, both red FIRE LEDs illuminate, the audible alarm sounds, and the shutdown time will start. The red FIRE LED will remain on until the fault condition is repaired. ACTUATOR Automatic Operation When a thermostat closes, current passes through the actuator and electrically fires it. The detonation of the cartridge produces enough force to drive the actuator stem through the nitrogen cylinder s rupture disc. When the stem punctures the nitrogen cylinder s seal, it releases pressure into the trigger line. Manual Operation The manual function is used when a fault exists that could inhibit auto/electrical detonation of the electric actuator via the circuit monitor or if fire is noticed before the the preset temperature sensor is reached. During a fire emergency, the driver would manually pull the disarming pin press the red FIRE button.

5 E4500 & J4500 Series Date December 2005 Page 8D-4 The automatic fire protection system has specific maintenance requirements regarding the scheduled replacement of components and the testing of the automatic alarm mode circuits. TESTING Semi-annual testing of the fire suppression system s automatic firing and triggering components should be performed to assure that they work correctly. The AMEREX squib simulator module is used to properly test the alarm mode circuit. NOTE: The Test button (below the Amerex Diamond) may be depressed to quickly check proper operation of all circuit monitor/control panel features. Holding the button down until the timer reaches zero will cause engine shut down. Alarm Mode Circuit Do not perform the following test with the electric actuator installed and electrically connected. A system discharge will result. 1. Clean all thermo sensors and the circuit monitor to remove dirt, grease and other foreign materials. Check sensors for dents, punctures or other damage and replace, if necessary. Check all power connection and wiring harnesses for cuts, abrasions or heat damage and repair or replace as needed. 2. Remove the electric actuator lead from the electric control head and attach it to the simulator module. 3. Depress the reset button on the simulator. The circuit monitor should indicate a normal condition with the green System OK LED illuminated. Exercise extreme care when performing this procedure. Assure that no hazards exist that could be ignited by the heat source. 4. Apply a suitable heat source near the thermo sensor until the contacts close. Test the function of each sensor individually. 5. When the sensor contacts close, the circuit monitor should enter alarm mode. The green System OK MAINTENANCE LED goes out and a red FIRE LED illuminates as described earlier. 6. Remove the heat source and allow the sensor to cool. The red FIRE LED should remain lit and the audible alarm will continue to operate. NOTE: During the test, the alarm can be silenced, however, the LED will remain illuminated until the system is reset. 7. Depress the reset button on the Test Module and the monitor will return to normal mode. Repeat this test for each of the thermo sensors. 8. Verify that all thermo sensors have cooled as indicated by the green System OK LED on front of circuit monitor. 9. Reconnect the electric actuator lead. REPLACEMENT Dry Chemical Cylinder & Discharge Valve 1. Remove the fired electric actuator from the control head. Replace the electric actuator. Reset electric control head following instructions included with the electric actuator. 2. Disconnect the discharge hose, fitting and retaining flange from the valve body. Install the anti-recoil plate. 3. Remove the two padded straps that secure the agent cylinder by removing the four 1/2 inch bolts, washers, and locknuts. 4. Replace the spent dry chemical cylinder and discharge valve assembly with a fully charged cylinder. 5. Resecure the cylinder into its mounting straps and reinstall the retaining flange, discharge hose fitting and connect hose. 6. Reattach the electric control head onto the discharge valve. Electric Actuator NOTE: Electric actuators have a maximum field service life of 6 years and a shelf storage life of 12 years. 1. Disconnect the electric actuator connector lead. 2. Connect the actuator simulator module to the connector lead. Push the reset button. The status of the fire suppression system should indicate normal. 3. Disconnect the simulator module. 4. Unfasten and remove the electric actuator from the control head.

6 Date December 2005 Page 8D-5 E4500 & J4500 Series 5. Install a new actuator into the control head. 6. Verify that the green SYSTEM OK LED is illuminated and the red FIRE LED is OFF on circuit monitor. Control Panel Module 1. Place battery disconnect switch OFF. 2. Disconnect the electric actuator. 3. Remove four mounting screws from the control panel. 4. Disconnect the wiring harness from control panel and remove. 5. Replace with new control panel and reconnect harness. 6. Perform an alarm mode circuit test as described earlier in this section. 7. Reinstall the control panel in the same location. 8. Reconnect the electric actuator. 9. Place battery disconnect switch ON. 10. Verify that the green SYSTEM OK LED is illuminated and the red FIRE LED is OFF on circuit monitor. SPECIFICATIONS Thermostats 1. Place battery disconnect switch OFF. 2. Disconnect the electric actuator and connect the squib simulator. 3. Disconnect the thermostat wire harness. 4. Unfasten and remove the thermostat from its mounting position. NOTE: Install the correct temperature thermostat in the proper location. 5. Reconnect the thermostat wire harness. 6. Check to see if the System OK LED is on. 7. Reconnect the electric actuator. 8. Disconnect the squib simulator. 9. Perform an alarm mode circuit test as described earlier in this section. 10. Place battery disconnect switch ON. 11. Verify that the green SYSTEM OK LED is illuminated and the red FIRE LED is OFF on circuit monitor. DRY CHEMICAL CYLINDER & DISCHARGE VALVE S/A Part Number... 3L THERMO SENSOR Part Number [280_F (138_C)]... 3L Part Number [350_F (177_C)]... 3L CIRCUIT MONITOR/CONTROL PANEL Part Number... 7L AMEREX SQUIB SIMULATOR Part Number

7 E4500 & J4500 Series Date December 2005 Page 8D-6 RESETTABLE FIRE ALARM SENSORS GENERAL DESCRIPTION The resettable fire alarm protection system provides audible and visual warning if a fire occurs in the engine compartment area. COMPONENTS The system consists of two automatically self-resetting alarm sensors, warning light and bell. The sensors mount to the rear cross seat panel, directly above the engine. The warning bell is located in the parcel rack junction box. This system is energized through the parcel rack junction box and connects by wire harness to the sensors (see Figure 2). ALARM SENSOR OPERATION If a fire occurs, the normally-open alarm sensors reach activating temperature and close and complete ground for the circuit. The circuit remains energized during the fire, and resets to the open position after the bimetal sensor cools. NOTE: The alarm sensor s activating temperature is preset at 360F (182 C). HARNESS Figure 2. Fire Detection Sensors C0651 MAINTENANCE LAMP REPLACEMENT 1. Turn disconnect switch to OFF position. 2. Unfasten and remove telltale cluster containing warning lamp from instrument panel. 3. Disconnect lamp from housing and replace.

8 Date December 2005 Page 8D-7 E4500 & J4500 Series SENSOR REPLACEMENT 3. Unfasten and remove sensor from panel and 1. Turn disconnect switch to OFF position. 2. Disconnect sensor harness from rear junction box harness. discard. 4. Attach new sensor and reconnect harnesses. SPECIFICATIONS SENSOR Manufacturer... Fenwal Part Number

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