Bob,
In a message dated 11/3/2005 12:49:58 P.M. Central Standard Time,
rbelshe@comcast.net writes:
I would expect that the
pump would just get hot if you powered both leads. It might trip
the breaker if you held power on long enough.
Yes, but how long before it gets hot? If you had the thermal
protection wire connected, then heat would stop the pump. In other words,
the pump gets hot when it runs continously.
Did you really get the pump to run in the "wrong"
direction some of the time? You said "at least six sequential
connections to both wires were made separated by a second or so
(Dn-Up, Up-Dn) and all but one resulted in the pump running primarily in
the down direction with foaming visible in the up direction tube.." Do
you mean the pump keeps running when you connect 12v to the "other"
wire? Do you mean it starts in one direction and then reverses when you
connect the second wire?
It ran in a direction when power was sequentially connected to both leads.
Yes. Yes. Yes.
If the pump ever runs
in the wrong direction it would open the wrong pressure switch and never shut
down!
No. At any pressure below the switch rated pressure, the switch
contacts are closed. If it ran "confused", it is possible that no pressure
would ever build up enough to OPEN any switch and it would just continue to
run confused.
Does anyone know how
this motor is wound? I think it is probably a series motor with two
field windings. It should be impossible to do what you
reported.
Try it on yours. Remember, I said if both wires were connected to
power at the same time, the motor would not run. Seems to me some winding
is more influential than another once action begins.
Also, it has been noted that the motor
relays are Ford starter relays. In automotive service they would
be starting and interrupting over ten times the current they see in our
application. Fusing of the contacts should be a rare (if ever,
occurrence). In the instance where relay power is left on for a
long time they could stick in the closed position due to an internal melt
down of some sort.
Not quite. The shellac-like winding coating and some other
construction goop will melt when overheated. Two results are possible
- jammed closed or slip sliding open when the power is removed from the
coil and, after the stuff cools and re-hardens, the relay can be
frozen shut or open. Mine was frozen closed as I had to pry the solenoid
core out when I disassembled the relay.
Thanks again for your experiment, and all
the good info you provide this group. Please don't take this as
criticism.
No way - Skepticism is useful to shake out the truth. Besides that
I'm a crusty old guy and a pilot to boot.
Like you, I'm just trying to understand
why people have so many problems with the LNC2 gear system.
Fortunately, I have had none, except for a
blown seal and a leaky (in one direction only) dump
valve.
Scott
Krueger AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL
(KARR)