Command module wiring

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by jay70cuda, May 14, 2018.

  1. jay70cuda

    jay70cuda Member

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    has anyone wired a rpm window switch to a command module? Like when the engine goes over a certain rpm the trans brake button stops working so you can’t accidentally hit it going down the track ?it all works off grounds but can you really run the trans brake ground thru the box and not short it out?
     
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  2. HootersFunnyCar

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    If it's an issue move the button or change the driver.;)
     
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  3. jay70cuda

    jay70cuda Member

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    Old clutch car and driver. Never used an auto before. Ish happens and don’t wanna find out the hard way. I don’t think I’ll do it but ignore I can wire in a fail safe why not.
     
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  4. rb0804

    rb0804 Member

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    Are you concerned with the command module restarting it’s timer functions or are you concerned about the re-application of the transbrake while in motion? I thought it was a standard operating procedure to have some sort of transbrake interrupt feature?
     
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  5. Mike Canter

    Mike Canter Top Dragster

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    You can use one of the fuel timers and set it to activate a relay after a set time such as .5 seconds. Then have the transbrake hooked to a normal closed contacts on the relay so at .5 seconds the relay activates and opens the normal closed contacts and shuts off power to the transbrake
     
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  6. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    I have also seen people wire the tbrake through a NC air over electric switch, hooked to the low gear air line. So when you shifted, it broke the circuit.

    The circuit Mike described would work. Your transbrake circuit would go into the relay on the 30 leg, come out the NC 87a. The 86/85 circuit could be triggered by a timer. In the case of a Command Module, the timer outputs are 12v, so you would hook that to the 86, and the 85 would ground.

    It's been a while since I have ran a Command Module car, but I'm assuming they still reset after 7.99 like a EM timer box does. At that point it should drop voltage to the trigger wire (86) and release the relay circuit.

    Here's what you need to keep in mind - 1. make sure the relay is isolated from vibrations. It's going to be hard to find a good 5 pole solid state relay. 2. I would probably run the 86 circuit from the timer wire through a switch. If not, you're going to have to wait 8 seconds every time to reengage the tbrake. This can be problematic if you use a planetary transmission behind a converter drive.
     
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  7. jody stroud

    jody stroud ZOMBIE Top Dragster

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    Put a delay box on it. Most have a t brake safety feature that disables it after you release it. My dedenbear is adjustable for that amount of delay .
     
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