[GreenKeys] Need motor for 50Hz supply (or DC)

[Malcolm Macleod]

Greetings all.

 

I have a 115V/60Hz Model 28 KSR that I imported to Australia some years
back.  My aim is to get this working on our local mains supply (230V 50Hz).
I'm happy to use a 230V/115V stepdown transformer if needed.  The bigger
issue is the change in mains frequency, and possibly gear change if the new
motor speed is 3000RPM (rather than 3600RPM).

 

Wondering if anyone can help with a suggestion as to which motor(s) and/or
gear sets I should be looking for.

 

The main resource I've been looking at is Teletype Corp bulletin 295B
(particularly page 67) ->
https://www.navy-radio.com/manuals/tty/295B-7012.pdf

 

Option 1: Am I able to run the existing 60Hz synchronous motor at 50Hz and
just change the gear set to accommodate the reduced RPM?  If so, what gear
set do I need for 45.4Bd/60WPM at 3000RPM?  I remember trying this a decade
ago on an ASR33 and it wasn't successful due to excessive heating of the
motor.

 

Option 2: Might I be able to run a 115V/60Hz 3600RPM series governed motor
on 50Hz?  If so, it seems I should be looking for an LMU4, LMU6, LMU41,
LMU57 or LMU61.  If it's acceptable to use an ASR motor in the KSR, then the
additional options (for 115V/60Hz) seem to be LMU14, LMU39 or LMU61.

 

Option 3: If it's not OK to run a 60Hz series governed motor at 50Hz, then
the 115V/50Hz options seem to be LMU38 or LMU50, though these will run at
3000RPM.

 

Option 4: I would also be fine of course with an LMU55 (230V/50Hz), though I
don't think I will be lucky enough to find one of these, and a gear change
would be necessary as well.

 

Option 5: Another alternative seems to be an LMU29 (Series governed
48V/3600RPM).

 

If you have any of these motors that you might be willing to sell, or
otherwise can shed some light in how to solve this problem, please let me
know.  I'm in the U.S. for the next couple of weeks, so can easily take one
back with me if there's one available there.  Similarly interested in
anything that might be available in Australia or the U.K. for local
shipping.

 

-------------- next part --------------
A non-text attachment was scrubbed...
Name: winmail.dat
Type: application/ms-tnef
Size: 5102 bytes
Desc: not available
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20260904/5c3becf7/attachment.bin>