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OK, so there i was at this ladies house today and after some tests i informed her that the pcb was the problem “no it’s not” she said, so i ask her why? and that’s when that dreadful answer rang in my ears “my husband said” it was the motor. So i informed her that i would replaced the motor but when it still didn’t turn i would still have to charge her for the motor due to the fact that i couldn’t send back a non faulty item, so a new pcb is on it way.
Anyway my reason for posting is this, can brush motors be tested out of the machine via the mains, i realize there are electrical test to determine the state of a motor but having a visual test that customer can see would help (especially today). How i was thinking was the live would go to the field windings and neutral to the brushes, i realize the motor would kick start at full speed so a heavy foot would be needed.
David
Re: Running a wm motor out of the machine
Have done it a few times with Hpt, Hvr, Bsh, Zn, Ind. etc. Never any problem. Live in through one brush, (via t.o.c.). Link wire from other brush to one field terminal. Neutral out from other field terminal. Earth to tag or casing. Plug in via RCD type socket for preference. Foot on motor (leave boot on 😆 ), switch on and immediately off again for quick burst test. If OK, try longer burst and check for clean running.
Mike.Re: Running a wm motor out of the machine
if you make yourself up a test lead, you can use a standard dimmer switch to control the speed. had one in the workshop for years. 😉
Re: Running a wm motor out of the machine
dpr1974 wrote:Anyway my reason for posting is this, can brush motors be tested out of the machine via the mains, i realize there are electrical test to determine the state of a motor but having a visual test that customer can see would help (especially today). How i was thinking was the live would go to the field windings and neutral to the brushes, i realize the motor would kick start at full speed so a heavy foot would be needed.
David
Why are you wanting to test the motor “live” in 30 years I have never needed to do this always used a meter. 😕 If you are doing this because the customer does’t believe you then a word of advice, walk away. Whatever you do you will not please them, if they cannot respect your professional judgement.
MalRe: Running a wm motor out of the machine
In 45 years I’ve never tested a motor like this either nor had reason to. What would be really scary is trying the figure how to connect up temporary link wires? So many makes of 6 and 8 terminal motors all configured differently leading to a nightmare finding the field winding/brushes terminal circuits from the motor plug terminals in order to safely plug it into the 240volt.
Holding the motor with your boot and plugging it in on the customers kitchen floor would fill me with dread. I suspect watching someone do that even scarier.
Having said that, years ago when the Hoover A3236H (Matchbox series) was around. They had DC controlled motors and I used to carry a module test rig on the van. That involved plugging a test lead into the motor block and plugging the module in this test rig, covering the module in a perspex shield then firing it up! The purpose being more to test the module than the motor in this case. But because the motor test lead was short it was a better option to take the motor out and put your foot on it prior to firing up the test rig. If you catch my drift?
Taking the motor out as well as the module took up too much of my precious time so I extended my test lead and left the motor in the machine. Didn’t fancy standing on the motor and plugging it in….no way!
Besides, these days this type of procedure would send any ‘Elf ‘n Safety official into a coronary arrest I would imagine. Long before he could throw the book at you no doubt. 🙂
Re: Running a wm motor out of the machine
we used to have a electrical jig ithe workshop that would run Hoover and Hotpoint motors until some idiot threw it out one day. Anyway like has been said testing motors with a meter, eye, and or megger has served me well and if a customer does not believe what I say then they need to find someone else to do their job, trust is the order of the day and if I get it wrong then thats my lookout not theirs, wonder is she has the same trouble at her dentists !
Re: Running a wm motor out of the machine
I agree with everyone on there comments, i just wish customers would believe what’s been said to them. I felt like saying to her that if her husband knew what the problem was, then you could have saved your self money by not calling me out.
I’ve always tested a motor the “normal” way and always will, i just got bloody annoyed at basically being called a lair, first time in 12 years so not too bad.Thanks all
David
Re: Running a wm motor out of the machine
I have a power supply in the workshop that delivers 30, 60, and 110 volts, and a vice on the bench, so I can hold a motor in the vice and run it up slowly to start with. This has been very useful over the years for testing them and bedding brushes in. I made up test leads to plug in Hoover and Hotpoint motors over the years using the plugs taken off the wiring looms of scrap machines but have also connected them just using leads with spade terminals.
A few years ago I bought a variable transformer [ like a Variac but an unknown make] at an auction for £7 which enabled a motor to be run up from zero to 240v; even more useful, but this packed up some time ago.
The dimmer switch idea sounds good; I think I’ll try that.
I don’t see anything wrong with bench testing motors in this way so long as the necessary precautions are taken to avoid accidents.
Re: Running a wm motor out of the machine
i would’nt live test a motor in the customers house. but as we have a shop and workshop, customers bring in motors for us to repair or test. after repairing, a live test in a controlled environment with the dimmer switch set up for a slow start is safe and gives you visual and sound proof that the motor is running correctly. this way when the customer gets it back home and theres still a fault you have no dought the fault is’nt in the motor. obviously the tacho coil gets meter checked and visual inspection on the magnet.
Re: Running a wm motor out of the machine
Just to clarify. I only do this at home. But I would do it on the customer’s premises if the need arose (in the back yard, taking necessary precautions ) after consulting with them and explaining my reasons, .
It’s especially useful when you’ve got a Bosch motor which has suffered commutator damage due to the long brush tails and you want to check your clean up job has been successful before re-installing the motor.
Mike.Re: Running a wm motor out of the machine
never thought of trying this before, but, dug out a motor tonight, dimmer sw & wired it, great idea, works well, cant see a prob doing it in house as with the dimmer you can start from a low input voltage, can also check voltage output from tacho
Re: Running a wm motor out of the machine
Putting dimmer switch on shopping list. Thanks guys. 😀
Mike.Re: Running a wm motor out of the machine
used to do this years ago most motors will turn slowly using 12 batt charger can use this to bed in bad brushes and leave it safely for hours in ness
if you want to use mains make a lead with lampholder in series used to use 100w but they are a bit scarce now then worst that can happen is lamp will light also lamp will slow down starting torque
Dave
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