Winding data for AEI BK-2410-C B56 motor? - Page 1
Forum section: electronics / general

author: CambridgeMart
author_rank: Regular Contributor
timestamp: February 02, 2021, 12:28:40 pm
content: My lathe suddenly started tripping the breaker and I discovered that there was a low resistance to earth from the windings. I've tried to price a replacement motor, but it's difficult to find a direct replacement due to the mounting arrangements. I had a couple of quotes for rewinding the motor and it was more than I paid for the lathe!I decided I'm going to rewind the motor myself, but working out how all the windings are interconnected is a nightmare; I know I could probably get the data from the EASA database, but membership of EASA is hugely expensive. Hoping someone may be able to help.The motor is an AEI BK-2410-C B56, it's 4 pole 3 phase 415/230V 1hp / 0.75kW, the stator has 36 slots.

author: GlennSprigg
author_rank: Super Contributor
timestamp: February 02, 2021, 01:37:29 pm
content: Wow... it really can be hard for the non-experienced, although it is really mostly amechanicalgrasping!I used to rewind tons of motors, as I had no choice when working in the bush many years ago!! ...If it is 4 pole, and has a total of 36 slots, then that's 9 slots per pole. So you 'should' find that each 'pole' wouldhave so many turns looping around say slots 1 to 9, which then connect with the same wire to so many turnslooping around slots 2 to 8, and so forth for slots 3 to 7, 4 to 6, for example. These groups of coils are madetypically on a layered wooden rectangular plywood 'former'...You then knock out the wooden/plastic bits covering each slots coils, and keep them for re-use.Chop the windings off at one end, and count the turns, and knock the windings out of the slot tunnels.When the new windings are loose & unvarnished, you can 'jiggle' them into the slots/cavities, before using aninsulating material like 'ElephantHide' to slide on top, before knocking in the top 'wooden' saved pieces.Later, varnishing will hold all the coils together properly, so there is no magnetic vibration. Connect the coilends as per the observations during dis-assembly. I don't know what more to say!!It's do-able, but not for the feint hearted... Good luck !

author: amyk
author_rank: Super Contributor
timestamp: February 04, 2021, 04:47:31 am
content: Go to archive.org and read some old books on motor winding. They should be very educational for you.

author: G7PSK
author_rank: Super Contributor
timestamp: February 04, 2021, 05:52:20 pm
content: I used to take motors and alternators to a local rewinder, if they did not have the details in a reference chart they just cut the ends of the windings and counted the end of the wires to get the number of turns.

author: alpher
author_rank: Frequent Contributor
timestamp: February 04, 2021, 09:45:11 pm
content: Rewinding 1Hp motor, it will cost certainly more than a new one.Such a small motor is a major pain to rewind and will probably cost more than bigger ones.What so spacial about it? isn't it a standard 56 frame ?

author: andy3055
author_rank: Super Contributor
timestamp: February 04, 2021, 11:29:29 pm
content: You may want to check the cost of winding wire, sleeving, insulation paper (letheroid and milinex) and varnish etc., before making the decision to go ahead. Baking can always be done with some high wattage bulbs. Never put it in an oven as the varnish can catch fire!Can you post pictures of the name plate and the interior of the motor?

author: CambridgeMart
author_rank: Regular Contributor
timestamp: February 06, 2021, 12:31:11 am
content: I've priced the rewinding cost and the price of materials is 1/4 the price of a rewind.The motor is an partially open style motor with a cover that attaches to the rear of the motor on 3 of the 4 studs; this rules out TEFC motors. It's also foot mounted which makes it even rarer.

author: alpher
author_rank: Frequent Contributor
timestamp: February 06, 2021, 03:58:39 am
content: Picture saves a 1k words.

author: WattsThat
author_rank: Frequent Contributor
timestamp: February 06, 2021, 04:53:11 am
content: Have you Googled “36 slot 4 pole 3 phase winding diagram” ?Rewind cost is virtually all labor. The only time rewind makes sense is when you have a non-standard frame or some wacky high pole count, oddball shafts or strange mounting arrangements. There is a reason for a shop to quote a high rewind price: they’d really rather not do it. Here in the US, it has gotten to the point where 20HP and higher is the current cost decision point for rewind or replace. I doubt it’s much different in the UK.Don’t overlook the fact that motors like yours are so cost engineered that the wire may not be a standard gauge. You get close and then find you cannot get the required number of turns into the slots or you break turns trying. Yes, it does look easier than it actually is, especially the first five or ten times.Given you’ve never rewound a motor before and without the winding forms, tools and proper materials, don’t expect it to work long term. Sure, it can be done but IMO, it’s a fools errand when it’s a bog standard piece of kit.New, open drip proof, foot mount 4 pole should about £50 new, maybe £100 worst case for a name brand.Unless the materials fall out of the sky for free and you don’t value your time whatsoever, I cannot imagine a case where it makes sense to learn how to rewind a motor, especially starting on a 56 frame. Just cleaning out the slots will be a real chore.

author: BrokenYugo
author_rank: Super Contributor
timestamp: February 06, 2021, 05:40:52 am
content: Can we gets pics of the motor and mounting arrangement? Making a modern standard motor fit is likely the path of least resistance here by an order of magnitude, V belt (I'm assuming) drives aren't picky about alignment.