Re: Relay Problem - Mystery Solved ??

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" <dhmccauley-at-spacecatlighting-dot-com>

Scott,

Disregard that schematic I posted.  I made a change to the schematic of just
switching my ENA and DIS leds on the pushbuttons, but forgot to move the
latch wire with those changes
as well.  So the schematic was in error (however it was wired in the
controller correctly)  Just a misprint. Sorry.

Dan


 > Dan -
 >
 > I'm really confused by your relay chattering problem, and the "solution".
 >
 > If your circuit is actually wired per your schematic, its not a latching
 > circuit, its a chattering circuit, and the relay MUST chatter as soon as
 > voltage is applied to the points labeled "control power". It can't work as
a
 > latching circuit if it is wired as shown.
 >
 > Per the schematic, one end of the relay's coil (leg L2) is tied to AC line
 > neutral (effectively, ground). The other leg (L1) is directly tied to
 > "control power" through normally-closed push-buttons PB4 and PB3B and
 > through the relay's normally-closed contacts. So as soon as "control
power"
 > is applied, the coil is energized (even if normally open pushbutton PB3 is
 > not touched). As soon as the coil is energized, the relay contacts open,
the
 > connection to "control power" is broken, and the relay drops out, which
 > again allows the coil to be energized, etc, etc resulting in the relay
 > continuously chattering as power is cycled to the relay coil.
 >
 > When normally-open pushbutton PB3 is actuated, the relay stops chattering
 > and stays energized because it is now directly connected to "control
power",
 > bypassing the relay contacts, but only as long as the pushbutton stays
 > depressed. As soon as PB3 is released, the chattering must resume. There
is
 > no self-latching function initiated by PB3 that I can see.
 >
 > If the schematic is correct, and there is a latching function initiated by
 > PB3, can you explain to a mechanical guy how it works?
 >
 > Thanks!
 > Scott Hanson
 >
 >
 >
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Thursday, January 16, 2003 5:47 PM
 > Subject: Re: Relay Problem - Mystery Solved
 >
 >
 >  > Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>"
 > <dhmccauley-at-spacecatlighting-dot-com>
 >  >
 >  > Well, after some major troubleshooting, I figured the problem out.
 >  >
 >  > Turns out the relay was being "current starved."
 >  >
 >  > I had used 16 AWG wire going through my latch circuit etc... and for
some
 >  > reason, it wasn't good enough.
 >  > Replaced the wire with 12 AWG and it works fine now.
 >  >
 >  > Dan
 >  >
 >  >
 >
 >
 >
 >
 >