Fire suppression system question

[Randy Folsom]

I put a G sensor in the power supply to my fuel pumps. In an accident over 10G the pumps automatically cut power. It has a simple reset push button. Fixed it to the chassis behind the dash on the door hinge area. Only ever gone off once when I spun off in a competitive event and bounced over very rough terrain!

I plan to put one in as well. They are simple but effective.

 

[Randy Folsom]

My cut off is going to based on a continuous flow solenoid spliced into the main battery cable right after the 40A breaker. The solenoid works much like a relay. The trigger is the ignition switch but before the ignition switch there will be a gauntlet that includes internal and externally mounted kill switches, an inertial switch, and something that breaks the circuit if the fire suppression system is activated. The kill circuit will also shut down the alternator. The piece I am missing is ensuring the automatic deployment of the fire suppression system breaks the connection to the solenoid. It could be a flap switch in front of the nozzle.

The solenoid is a Cole Hersee 24213 12V 200 Amp.

 

[Randy Folsom]

I have given up on the idea of the Fire Suppression activation cutting off the fuel pumps. Instead I am thinking to use a thermal switch inline with ignition switch, inertia switch, kill switches, etc. A typical hot water heater thermal switch triggers between 150 and 180 F (65-82 C). That aligns nicely with the red thermal bulbs used by Lifeline fire suppression system. Just mount them in the same general location on the firewall/bulkhead.

Bulb Temp Options
Orange - 135°F / 57° NOT SFI CERTIFIED
Red - 154ºF / 68ºC >> Default Choice
Yellow - 174ºF / 79ºC
Green - 199ºF / 93ºC
Blue - 286ºF / 141°C
Purple - 360°F / 360°C NOT SFI CERTIFIED

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10lbs Auto + Mechanical

www.lifeline-fire.com

 

[Randy V]

I have given up on the idea of the Fire Suppression activation cutting off the fuel pumps. Instead I am thinking to use a thermal switch inline with ignition switch, inertia switch, kill switches, etc. A typical hot water heater thermal switch triggers between 150 and 180 F (65-82 C). That aligns nicely with the red thermal bulbs used by Lifeline fire suppression system. Just mount them in the same general location on the firewall/bulkhead.

Bulb Temp Options
Orange - 135°F / 57° NOT SFI CERTIFIED
Red - 154ºF / 68ºC >> Default Choice
Yellow - 174ºF / 79ºC
Green - 199ºF / 93ºC
Blue - 286ºF / 141°C
Purple - 360°F / 360°C NOT SFI CERTIFIED

Amazon.com: Bradford White 2394367602 THERMAL SWITCH, RESETTABLE : Automotive

Buy Bradford White 2394367602 THERMAL SWITCH, RESETTABLE: Thermal Limiter - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

a.co

10lbs Auto + Mechanical

www.lifeline-fire.com

I’m not so sure that’s a great idea - but certainly subject to your plan on implementing.. For instance, a coolant temperature sensor does a great job of sensing and reporting the temperature of the coolant that surrounds the probe, however, it will do a poor job if sensing air temperature in the event that you run low on coolant and the probe is no longer submerged..

 

[Randy Folsom]

I’m not so sure that’s a great idea - but certainly subject to your plan on implementing.. For instance, a coolant temperature sensor does a great job of sensing and reporting the temperature of the coolant that surrounds the probe, however, it will do a poor job if sensing air temperature in the event that you run low on coolant and the probe is no longer submerged..

Thx much. I am hoping that the water heater sensor will trigger in the event of a fuel fire. It might not. I will use a heat gun and an infrared thermometer to test. It actually needs to trigger before the fire suppression system or it won’t trigger unless the fire returns after the suppression system has been exhausted.