Confusing motor connections – 240v motor

[ell81Participant @ell81]

So here is the motor:

It’s definitely 240V

It was running on 240 before I took the lead off it.

So, it looks like a 3 phase, but it was running on single. Which one is the live, and which is the neutral? Thanks.

[John HaineParticipant @johnhaine32865]

The terminal block is dual purpose but the motor must be single phase if it ran on single phase.  Does it have a capacitor for start or run (or both)?   What is its power rating?

 

[noel shelleyParticipant @noelshelley55608]

Are there not diagrams above the terminal block ? There are tags on the leads what do they say ? Is there a capacitor on the motor ? The data plate should give some clues.

2 wires for run, 2 wires for start, 2 wires for the cap, and then the centrifugal switch, there may also be a thermal trip/overload.  Need more info. Noel.

[ell81Participant @ell81]

Here are more pics:

Everything was in the terminal box, no seperate capacitor box

[BazyleParticipant @bazyle]

Rather than a capacitor it may have a start winding and a centrifugal switch. The two diagrams are showing you how to swap the connecting links for clock and anticlockwise rotation.

[BazyleParticipant @bazyle]

This looks similar

https://electronics.stackexchange.com/questions/459566/connecting-single-phase-motor-to-uk-mains-ac

[SillyOldDufferModerator @sillyoldduffer]

More information please! Can’t tell much from the terminals alone. Motor plate, who made it, what the motor powered, circuit information etc.  How big is it?   Helps if photos are the right way up so the writing can be read.

Also, what else is visible: this photo is tantalising!   I can see a capacitor, but it may be a suppressor.

There are at least 7 different types of single-phase motor and 3 don’t need capacitors.  But confusion abounds because the capacitor may not be part of the motor, or is hidden inside.   Also possible to run a 3-phase motor on single-phase (yuk), or for the motor to be DC with a rectifier hidden inside.

I don’t recognise the mix of terminal markings:  X2U2,   R1, X1, U, U1,  R2.  Let’s hope an expert will know.  Just a guess but R1 and R2 might be ‘reactor’ connections.  This is a motor type where the phase shift between the start and run windings is provided by an inductor rather than a capacitor.   If so I’ve never seen one outside a book!

Dave

 

[ell81Participant @ell81]

Thanks for your replies, but R1 turned out to be neutral and U was the live. Cheers.

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