On 2008-02-05, Fred warydragon--at--gmail.com wrote:
Richard Edwards wrote:

[ ... ]

After running about an hour this morning and turning off normally with
the SA switch (apron lever) the K2 (forward) button is staying in 3 to 6
seconds, then clicking out. Comparatively, the reverse relay clicks out
almost instantaneously with the SA switch.

Hmm ... this looks to me as though it is a problem with contacts
in the "SA" selector switch not opening quickly -- or perhaps drawing an
arc which sustains for a few seconds before releasing. Is the SA switch
the block of black plastic with six terminals below the KM1 relay? Is
there a rod going from that through the side of the box and becoming the
switch rod connected to the apron lever? It doesn't look right, because
I don't see anything connected to terminal "4" on it (and I *think*
nothing connected to "3" either, so I suspect that SA is somewhere in
the pedestal at the end of the rod.

Anyway -- locate where the SA switch *really* is (and it should
be mechanically connected to the rod from the apron), and then run the
lathe until you have it hang up as described above. Then unplug the
lathe, and reach down to feel the switch. I suspect that you'll find
one pair of terminal screws are hot compared to the other two pair.

As for the relay itself -- try this -- with power to the system,
so be careful what you touch -- ideally, press the buttons in the
relays with insulating rods (plastic, dry wood, or whatever):

1) With the SA switch in the "STOP" position

2) Hold in the black button for KM1.

3) While holding it in, press in the black button for KM2.

The motor should start, and release immediately when you release
the button on KM2 or KM1. Either should pop out quickly instead of
after a delay.

If the relay moves slowly, then it is the relay. If it moves
quickly, it is more likely to be arcing in the SA switch -- or perhaps
just gummed up contacts which don't want to move easily once warm.

And I agree -- the diagram is a pretty bad one. More detail
about the SA switch would be nice.

Good Luck,
DoN.

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