Navitron Renewable Energy and Sustainability Forum

CHP (combined heat and power) => Internal Combustion (eg diesel/gas/petrol engine based systems) => Topic started by: pmoc_2001 on July 27, 2010, 06:55:20 PM



Title: Would anyone like to help a new and inexperienced Lister owner?
Post by: pmoc_2001 on July 27, 2010, 06:55:20 PM
Hello,

I have recently finished restoring the prime mover (SL1) SOM generating
set. I have now moved onto the generator itself. The SOM functions work correctly (Auto start)
however, the plant shuts of after 30secs or so as it is not getting up to
voltage and the thermal switch engages.

I am stumped with regards to the voltage output. It is only producing about 30v at
load end with a 60w light bulb attached. I have adjusted the rheostat to both
minimum and maximum setting and in between and there has been no difference in voltage output.
Any advice from this experienced group would be greatly appreciated.

Best regards


Casper


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: camillitech on July 28, 2010, 06:04:47 PM
Hi Casper,

I've had and maintained a few SOMs in my time but I'm an electrical numpty so probably not much use. Obvious things are to check the DC brushes and the AC sliprings/brushes and clean all the contacts in the box. Despite not actually knowing anything about electrickary I've always managed to fix mine (well almost  ;D)

Perhaps ecogen can help, he seems to be a wizard with these things.

Good Luck, Paul


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: pmoc_2001 on July 29, 2010, 10:52:34 AM
Hi Paul,

Thank you for your reply. The AC Slip rings look clean. However as you point out, the DC grooved commutator requires a clean. I've checked the brushes and they appear good and I can see signs of fresh wear after I had it running for an hour. Is their any way to remove the Brush/Contact frame from the Generator housing. I ask because I want to clean the Commutator with fine glass paper and it is quite tight in there.

Also, and sorry for all the questions, how can I test if the gen is exciting correctly?


Regards


Casper


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: camillitech on July 29, 2010, 11:42:30 AM
Hi Casper,

what I've always done in the past and bear in mind this could be construed by the 'elf an safety' types as suicidal so would never recommend anyone else try this. Get a long wooden stick that's flat at the end and will just fit through the brush holder and rest on the commutator, wrap your fine wet or dry on the end then start up the generator and clean whilst running  ;D Once that's done I just wash it off with meths.

Of course I'm not suggesting that you should do something so foolish as there is an obvious risk of loosing fingers or electrocution but it beats the cr*p out of taking the back off the alternator to remove the brush housing and my opinion does a better job.

The other obvious thing to check is that the brushes are free of course.

Hopefully someone who actually knows what they're talking about will be along shortly  ;D

Cheers, Paul   


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: Fintray on July 29, 2010, 01:00:23 PM
Paul

As an elf "n" safety type please don't go on about elf "n" safety types stopping anyone from doing risky activities at home. You can if you so wish stick your fingers or any other bodily part into rotating machinery accepting that bits may get removed. However if you were at work and your employer asked you to do such a task I expect you would say F*** That!
Anyway back to the topic and you can buy a commutator cleaning stick specifically for this task:
http://shop.ukwhitegoods.co.uk/Tools+%252526+Glues/Washing+Machine+Motor+Commutator+Cleaner.html
 (http://shop.ukwhitegoods.co.uk/Tools+%252526+Glues/Washing+Machine+Motor+Commutator+Cleaner.html)

regards

Ian


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: djh on July 29, 2010, 01:49:40 PM
As an elf "n" safety type please don't go on about elf "n" safety types stopping anyone from doing risky activities at home.

So I don't need to put a TMV on my bath taps then, as long as it's at home?


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: camillitech on July 29, 2010, 02:21:42 PM
Paul

As an elf "n" safety type please don't go on about elf "n" safety types stopping anyone from doing risky activities at home. You can if you so wish stick your fingers or any other bodily part into rotating machinery accepting that bits may get removed. However if you were at work and your employer asked you to do such a task I expect you would say F*** That!
Anyway back to the topic and you can buy a commutator cleaning stick specifically for this task:
http://shop.ukwhitegoods.co.uk/Tools+%252526+Glues/Washing+Machine+Motor+Commutator+Cleaner.html
 (http://shop.ukwhitegoods.co.uk/Tools+%252526+Glues/Washing+Machine+Motor+Commutator+Cleaner.html)

regards

Ian

Hi Ian,

you are of course completely right, sadly I am one of those who have spent most of their lives self employed so even though I now work for someone else, if his commutator needed cleaning I'd do the same thing without being asked. Of course at 54 I am now paying the price for thirty years of diving, mostly outside of HSE guidelines, my back is sore, my hearing terrible and all my joints ache. Yet every year when I go for a medical my doctor remarks on how fit I am. Your profession/position/stance or whatever fulfills a very important function but when some overweight clown comes along and tells me that I must use lifting equipment to move a 30kg diving cylinder I feel like throttling them  ;D

Like I said it is dangerous and I wouldn't recommend it and I didn't mean to cause any offense, it's just that you would not believe some of the cr4p that our safety people come out with and lets be totally honest, it's not through any concern for their employees but for fear of litigation from the multitude of sharks out their working on a no win no fee basis.

Anyway, back on topic, if the piece of wood is long enough then it is actually no riskier than crossing the road, the beauty of doing it whilst the engine is running is that it works like a lathe and gives a very even finish.

Cheers, Paul


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: Iain on July 29, 2010, 02:35:13 PM
Hi
If you can lift the brushes prior to cleaning it would be a lot better(some brushes can lift up a bit and the spring arm rests on the side of the brush and holds it off the slip ring or commutator). We used to call them a "zob stick" for some reason many years a go. We were told to use glass or crocus paper but never emery cloth.
Iain


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: ecogen on July 29, 2010, 05:24:42 PM
Quote
Perhaps ecogen can help, he seems to be a wizard with these things.
Paul, I'm sorry, but you have been seriously misled.
Picture.... Yellow wellies (Hunters of course), Pink Marigolds and Orange head torch. Oh and a black bin bag if it's raining. Apparently during unfortunate encounters with angry electrons a good impression of Crusty the clown is given.

Quote
Get a long wooden stick that's flat at the end and will just fit through the brush holder and rest on the commutator, wrap your fine wet or dry on the end then start up the generator and clean whilst running.
This is the correct way it is done, perfectly safe when done properly and normal practice. For larger machines the piece of wood should have the end cut to the radius of the commutator of slip rings. For periodic cleaning while in service a canvas "mop" should be fashioned onto the end of the wooden stick. Two strips of canvas from an old army rucksack or belt are ideal.
On reassembly after a rotor's comm / rings have been turned, a carborundum stone or fine silicon carbide paper is used to remove the high spots off the turning.
Sand paper or silicon carbide / carborundum paper is used to bed new brushes by wrapping around the comm / rings and turning the set over slowly. Emery cloth should not be used because of possible conductivity. It contains Magnetite, which when wrapped around the end of your ring polisher and pressed firmly into place whilst running live, can heat up and potentially exhibit metal like conductivity.

Casper. I second Paul's advice on first cleaning the comm ect. Can you identify the alternator make / model. I will risk a guess at a Brush SCA 117. as fitted to the SR1.


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: Baz on July 29, 2010, 06:20:10 PM
You said initially it didn't get to voltage and the thermal switch cut out. That seems more like a short circuited coil.
However as it is I think designed to start when a load is detected does that mean it needs a load on it to keep it going?


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: Baz on July 29, 2010, 06:36:13 PM
ooops you said you had a bulb on it.


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: Fintray on July 29, 2010, 08:12:07 PM
Paul

No offense taken  :) Having been in a production environment for the first 30 years of my working life (not in elf n safety) my views on the subject are biased with the practicality of getting the job done but in a way that minimise the risk to the employee. It's true some elf n safety people require a slap now and then!  :fight


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: pmoc_2001 on July 29, 2010, 08:25:06 PM
ecogen,

I really can't say what make or type the generator is. It has a Lister name plate, perhaps it is a re-badged Brush. I like the idea of a stick with fine wet and dry paper on the end. I will post some pictures of the name plates as soon as I can. For now, here are some pictures I took on the day I got it. Started first time after 20+ years sitting idle.
http://renew.mine.nu/index.php?option=com_content&view=article&id=46&Itemid=54 (http://renew.mine.nu/index.php?option=com_content&view=article&id=46&Itemid=54)


regards


Casper


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: Alan on July 29, 2010, 10:26:10 PM
Hello Casper

From the drawing.

To start, switch S1 is pushed. This energises relay SC1 and coil FCS

Contact SC1 starts the engine rotation by energising the commutator.

Engine starts if your lucky.

A.C. Voltage is produced and rectified into D.C. To energise relay LC

Relay contact LC1 rectifies A.C. Voltage to energise relay D1

Relay contact LC3 opens and start relay SC is deenergised.

This stops the generator being a starter motor.

Contact of relay D1 keeps the system running when your finger is removed from the start button.

The other three contacts of LC keep the system operating and the battery charged.

Excitation is maintained by voltage produced by coil FCS

Simplified description of operation.

My understanding. No prior knowledge of Lister bits.

What battery are you using. ?

Where are you located.

Regards

Alan


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: ecogen on July 29, 2010, 11:10:49 PM
Your alternator was made by BKB. I don't know the model or possess any technical data for it. You have the machine schematic which is all you need to assist in fault finding. It is good practice to check winding insulation resistance first, to ascertain if the machine requires drying. Dampness is a common cause of winding failure.

Quote
Excitation is maintained by voltage produced by coil FCS
FCS is the fuel control solenoid, note the two coil windings and switch FCS1 to cut out the pull in coil.
Excitation is provided by the DC armature and field winding EFW.


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: pmoc_2001 on July 30, 2010, 10:40:12 PM
Thanks for the advice. I'm on leave for a week now and will revisit the problem then.  I am. Located in rutland at raf Cottesmore doing this on mobile not easy. Typing that is.


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: pmoc_2001 on August 02, 2010, 09:07:26 PM
Got it working at 230v. I used the long stick and wet and dry approach. Thanks for all the good advice.

My next challenge is to hook it up to my inverter/charger as a solar top up facility on cloudy days. Then for the air 2 air heat exchanger.

I have noticed that the control box must be fixed upright or the relays trigger indiscriminately.

Awesome forum guys.


Title: Re: Would anyone like to help a new and inexperienced Lister owner?
Post by: camillitech on August 02, 2010, 09:42:17 PM
Got it working at 230v. I used the long stick and wet and dry approach. Thanks for all the good advice.

My next challenge is to hook it up to my inverter/charger as a solar top up facility on cloudy days. Then for the air 2 air heat exchanger.

I have noticed that the control box must be fixed upright or the relays trigger indiscriminately.

Awesome forum guys.

Glad you got sorted pmoc,

just a tip on the autostart via inverter, a friend of mine who has been wiring up 'Startomatic's' since Adam was a lad wires the detection circuit through two bulbs in parallel, that way they will never blow and let you down.

Good luck, Paul