DoN. Nichols wrote:
According to George :
After being in storage for about 10 years I have relocated an old
Herbert 4 Senior Lathe to a new workshop. I was working previously via
a 3 phase converter but it did work OK. It was sprayed with oil prior
to storage and it all looks in quite good knick.
When I powered it all up I could not get the pre-optive motor to
operate for a while. I found 3 small 5 amp fuses, some of which had
blown, - not violently, just not connected and a few other problems.
[ ... ]
Aha! I thought, now it will be OK. But no, even with the pre-op. motor
running and the speed selector apparently free, the main motor would
not come on. Previously there was a big click of the power relay(s)
when you pushed the forward, reverse or inch buttons. Then the pre-op.
trip tripped again (as it always used to if left running for a while
due to the converter not giving true 3 phase), when I reset it the
jamming was there again.
Hmm ... you are operating it from a "static phase converter"
such as those made by Phase-o-Matic? If the pre-op motor is a single
phase motor, it (and the various control relays) will be sensitive to
which two of the three phases they receive power from. They must be
powered from the two wires which go through to the 220V single phase
line, as those are the only two which are sure to have power.
I'm presuming that you had the converter stored separately, and
had to re-connect the lathe to the converter. What I would suggest is
that you disconnect the three phases from the converter (or from the
plug, if you have set it to plug into the converter, but that would
probably not have changed the wiring), connect each wire to the terminal
to which the next one was connected, and try again. If that doesn't
fix it, try the same change again once more.
Yes -- there is a more analytic way to do this, but since you
say that you don't have the manual for the machine, this should be
easier.
Hmm ... another consideration -- the start capacitor in the
phase converter may have died while it was in storage.
If you're using a rotary converter, or a VFD, then things should
be simpler.
Does anyone know enough about this old Lathe to suggest what may be
wrong and does anyone have either a circuit diagram or handbook (or
both) that I could beg borrow or buy.
I must admit to never having even *heard* of this brand of
lathe, and I'm not quite sure what a "pre-optive" motor does. My guess
is that it may adjust the variable speed pulleys.
I am sure there is not much
wrong with it and I really don't like to attempt the dismantling of it
to get into the pre-optive gearbox assembly.
I'm willing to bet that there is nothing wrong with the lathe
(other than a few blown fuses), and that the problem is either with your
phase converter, or with its connection to the lathe.
Any comments or suggestions would be welcome. It is a fine machine and
I am sure I can put it to good use again.
You have my suggestions above.
Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---
In spite of not knowing my lathe you may have hit it on the head. I
did change the wiring from the 3 phase converter. I used it for a
pillar drill and the phase rotation was wrong so after checking that it
was correct rotation for the lathe I did not check which one was the
"dead phase, It only come up to voltage when the motor load comes on
and although the pre-optive motor is 3 phase it is very small and not
enough load on the converter, I feel.
The preoptive motor allows on-the-move speed changes to be selected
prior to requiring the change - at which time you just press a button
and it changes , rather like using an epicyclic gearbox on a car.
Herbert is very well known in UK and there are a lot still about. Mine
is far too big and complicated for what I do with it, but it is better
to have a lot of facilities and not use them than not having enough and
always getting stuck.
Thanks very much. I shall try your advice tomorrow, or Friday as I
shall be busy tommorrow morning. Regards George.