[GreenKeys] 35-KSR - 50Hz gears

[Jerry Murphy]

-----Original Message-----
>From: Jim Haynes <jhhaynes at earthlink.net>
>Sent: Dec 8, 2014 8:02 PM
>To: gfmurphy at earthlink.net
>Cc: Green Keys <greenkeys at mailman.qth.net>
>Subject: Re: [GreenKeys] 35-KSR - 50Hz gears
>
>So I guess you are saying they just let the motor run hotter on 50 Hz.
>
>jhhaynes at earthlink dot net
--------------------------------------------------------------

Hi Jim:

The Model 28 motor parts book (BSP Section 570-220-800TC) shows the
151795 motor as being suitable for use on both 50 and 60 Hz.  The
151795 motor consists of the rotor, stator and end bells.  It does
not include the base, relay, capacitor or thermostatic switch.  The 
151795 motor is used on both the LMU3 (60HZ) and the LMU38 (50HZ).

BSP Section 570-220-100TC shows the LMU3 having a running current of
1.85 Amps at 115 Volts and 60HZ.  The LMU38 has a running current of
2.4 Amps at 115 Volts and 50HZ.  Heat dissipation of the LMU3 is 50
watts while the LMU38 dissipates 70 watts.  The engineers seem to be
satisfied that the 1/20th HP motor can handle the additional heat.

The engineers went with a different design when they came up with the
1/12th HP motor used on 50HZ current.  The 1/12th HP 50HZ motor 
(LMU50) draws 2.68 Amps at 115 Volts while the 1/12th HP 60HZ motor 
(LMU12) draws 2.8 Amps at 115 Volts.  The LMU50 dissipates 62 watts 
while the LMU12 dissipates 70.6 watts.

Jerry Murphy