New Century motor, new drum switch, old and stupid mechanic .......

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OK - I'm needing to wire a new Century 3/4 hp motor, set up for 220V (where I'd like to keep it) , to a new 6 terminal drum switch.
The switch contacts look to be set up to connect "hockey stick" style, but I'm totally confused by the motor wiring - I tried 2 different arrangements, and both times it was a no go - Motor makes horrible growling sounds, capacitor gets hot - I'm on the verge of cooking it, so I'm stopping here.
I've direct wired the motor, and swapped the red / black reversing terminals, and it starts and runs fine that way - But I don't understand the switch wiring.

Here's a couple photos, of the motor schematic, and the drum switch layout. I just need help to wire this switch -
My brain is far too old to absorb much motor theory, so if someone has a cookbook recipe to get this wired, I'd be mighty grateful.
I hope someone can help.

 

[markba633csi]

You don't have the best style of drum switch for that, but I think we can make it work
One has to sometimes "hot wire" newer motors to work with these old fashioned drum switches
Here we can do the swinging start leg trick:
OK, try this-- Configure the motor for high volt, and unplug the black wire from motor Line lug 6 and extend to reach drum switch 4
Connect the two remaining motor line lugs to the drum switch as shown
To invert motor rotation to match switch handle swap wires at drum switch terminals 2 and 6 (if required)

PS be sure to ground the motor and drum switch cases also- especially important for 240 volt operation

 

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It just figures that I would wind up with a mismatch - The story of my life :~)
OK, I'll try this today, and report back.
And YES - Grounding, I do understand - Motor and switch are connected with BX type flex conduit, ground wire fed though, and secured at both ends!

Thank You !

 

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Mark - You are beautiful !!
This worked perfectly, first time around, and I didn't even need to swap 2 & 6 !

I recall, when I was looking for a solution yesterday, that I saw one of your old posts, trying to help someone sort out a drum switch, where you told another poster that you thought about writing a book, just on drum switch wiring.
Well, if you ever decide to do that, please reserve the first copy for me - Whatever the cost!
You obviously have a deep understanding of this stuff - It would have been impossible for me to figure it out on my own.
Many, many thanks !

 

[markba633csi]

Good news! Yes I have already enough sketches to make a book, but I'm not sure if that's the best approach-
I'm thinking about a generic analysis tek that would enable anyone to have success with any switch and motor combo
Tough problem! Not an easy thing to accomplish without getting into too much theory

 

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There's theory, and then there's applied theory - If you take the latter approach, and illustrate the theory with actual examples of it, as it's applied to a wiring situation, I think it would go down a lot easier for many people. I know it would for me.
I hope you do pursue this at some point - It would be a benefit to us all.
Thanks again

 

[markba633csi]

That's it- I'd rather try to teach fishing instead of giving out sardines to all the cool cats on this forum

 

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I totally get it, but sometimes, a sardine really hits the spot ;~)