Frame sizes at this rating
IEC: 315, 355, 355M
The number is the shaft centre height in millimetres and the
letter is the frame length. It fixes how high the shaft sits and where the foot holes
are, so a 132M from one manufacturer mounts like a 132M from another.
Synchronous speed
750 rpm — 750 rpm
at 50 Hz, from 8 poles.
Full-load speed is lower than this by the motor's slip, and slip is
not recorded in the register. Read it from the nameplate of the motor you are replacing.
Efficiency spread
Full-load efficiency across these registrations runs from 94.30%
to 95.40%.
Over a motor's working life, running cost usually dwarfs purchase
price, so this spread is worth more attention than it normally gets.
Replacing a motor?
What each figure on the nameplate means, which of them decide whether a replacement fits,
and which you have to confirm off the drawing.
Read the guide →
Match against your specification
Add voltage, frame, mounting and enclosure to narrow these 4
registrations to the ones that meet your requirement.
Open the finder →
Known limitations
What the register omits, where family registrations blur model detail, and the checks you
always have to make yourself.
Understand the gaps →