europa-list
[Top] [All Lists]

Re: Charge Indicating Lamp

Subject: Re: Charge Indicating Lamp
From: Robert L. Nuckolls III <nuckolls@aeroelectric.com>
Date: Fri, 5 Feb 1999 09:14:45

>If it's the fat, clear plastic high intensity device from  radio shack,
>that critter can easily take 60 milliamps  and the light output will fry
>your retenas . . . a very attention getting device.>
>
>It is! How did you know? I guess you're saying its OK to use - but I
>apparently have to fit a 680 ohm (thanks Tony) resistor (presumably in the
>+VE side). Fortunately I usually wear sunglasses when flying!

  The resistor can go in either lead . . . current is the same
  all the way around a series loop.

>Does the fact that its working for the 'starter engaged' warning mean that
>it has a built in limiter so perhaps I don't need the resistor after all?

  Opps! Starter engaged?  If your alternator indicator light allows
  you to ground one side of the lamp, then you can have both
  starter power -and- alternator failure drive the same lamp
  but you may want to include some diodes or perhaps it will take
  two resistors. Let's get together for lunch or something and
  scope this out.

>My Mitchell oil pressure sender arrived today but my instrument still reads
>100 psi (max) when I turn power on. Is the circuit expecting a single wire
>from sender to instrument 'cos I have a plug in the middle so that my
>modular panel will easily go in and out (for which I am getting plenty of
>practice).
>
>Thinking that somehow resistance is being used to transmit the oil pressure
>via the sender I wonder if the plug is influencing the reading?

  Does the indicator read full scale with the sender disconnected?
  It may be that you're missing crankcase ground for the return
  side of the sender. Is  your ground system fully installed?


       Bob . . .
                       ////
                      (o o)
       <  A mind abhors a vacuum . . . >
       <   When deprived of facts,     >
       <  our fantasies are generally  >
       <   much worse than reality.    >


<Prev in Thread] Current Thread [Next in Thread>