Failure of electronic parts in old machines

Jayesh Shirpurkar · Aug 31, 2009

Recently we have purchased some used machine tools from UK.
The machine were without power from last 6 months. Now while power up in India, I'm observing thye failures in Electronics like Power supply modules of drives & CNC. The PCB are contaminated with oil & dirt. The Input voltages are OK. Can anybody suggest how to overcome this problem? Does it require to clean all electronis in the machines?(More than 50 CNC machines). Any suggestion....

leitmotif · Aug 31, 2009

Used machinery does have its problems of course. Sometimes you can do very well other times as you see you bought someone elses problems.
CAVEAT EMPTOR
Why do you think they sold it?

I suppose management thoght they were getting a great bargain, had them shipped, you had nothing to say about this yet then they are dumped them in your lap, and now you have to get them running. Been there done that.

Do you have the manuals prints etc etc?
Are the programs still valid?
Are the backup batteries still good or did they discharge and now you have lost the program?
Do you have backup copies of the programs?
Are you positive you have them connected to the correct voltage?

IF all the above check out OK and you are able to confirm a bad board the last ditch option for boards or cards covered in oil and dirt you may be able to salvage them. Wash them with warm soapy water (dishwashing detergent works well) using a soft paint brush rinse with clean water twice then rinse with alcohol and let air dry at no more than 100 F (about 72C ??)

Dan Bentler

keithkyll · Aug 31, 2009

leitmotif said:
Wash them with warm soapy water (dishwashing detergent works well) using a soft paint brush rinse with clean water twice then rinse with alcohol and let air dry at no more than 100 F (about 72C ??)
Dan Bentler

(100F = 38C). I agree. Water soluble cutting fluid is used in machine shops. It gets airborne and condenses on the boards. The gunk absorbs moisture.
Clean them and they will work. Warm to hot water. Compressed air to dry. N2 is better. Isopropyl Alcohol (IPA) will help - it displaces water.
Most electronics can handle water. Keep transformers and batteries dry.

leitmotif · Aug 31, 2009

keithkyll said:
(100F = 38C). I agree. Water soluble cutting fluid is used in machine shops. It gets airborne and condenses on the boards. The gunk absorbs moisture.
Clean them and they will work. Warm to hot water. Compressed air to dry. N2 is better. Isopropyl Alcohol (IPA) will help - it displaces water.
Most electronics can handle water. Keep transformers and batteries dry.

OOPs did F to C conversion off top of head - obviously forgot to subtract 32 and obviously forgot to check calcs.

Dan

keithkyll · Aug 31, 2009

A formula I learned years ago from Radio Electronics.
C-F. Double it, subtract 10%, add 32. A little harder to do backwards (F-C). In this case, I cheated and used Convert from Josh Madison. A nice, free program.

James Mcquade · Aug 31, 2009

stop your wiring.
the power wiring from the UK is different from what you are probably used to. look at the part numbers of the devices.

for example:
120 volts in the US is 230 volts in the UK
220 volts 3 phase is 380 volts in the UK.

also, the frequency may be 60 hz in the UK as opposed to 50 hz in the UK. this alone will burn the electronics up within 3-6 months(based on experience).

regards,
james

Brian123 · Aug 31, 2009

keithkyll said:
A formula I learned years ago from Radio Electronics.
C-F. Double it, subtract 10%, add 32. A little harder to do backwards (F-C). In this case, I cheated and used Convert from Josh Madison. A nice, free program.

You can cheat using Google too. Punch in "100 f in c" and it will spit out the result. Works everywhere the internet goes. Google does all sorts of different conversions.

Brian

Jayesh Shirpurkar · Sep 2, 2009

James Mcquade said:
stop your wiring.
the power wiring from the UK is different from what you are probably used to. look at the part numbers of the devices.

for example:
120 volts in the US is 230 volts in the UK
220 volts 3 phase is 380 volts in the UK.

also, the frequency may be 60 hz in the UK as opposed to 50 hz in the UK. this alone will burn the electronics up within 3-6 months(based on experience).

regards,
james

Fortunately Electrical standards in UK & India are same, 415V for 3Ph & 230V for 1 phase, @ 50 Hz. I confirmed the same from machine manuals & machine nameplates. So Power is not the issue.

Jayesh Shirpurkar · Sep 2, 2009

leitmotif said:
Used machinery does have its problems of course. Sometimes you can do very well other times as you see you bought someone elses problems.
CAVEAT EMPTOR
Why do you think they sold it?

I suppose management thoght they were getting a great bargain, had them shipped, you had nothing to say about this yet then they are dumped them in your lap, and now you have to get them running. Been there done that.

Do you have the manuals prints etc etc?
Are the programs still valid?
Are the backup batteries still good or did they discharge and now you have lost the program?
Do you have backup copies of the programs?
Are you positive you have them connected to the correct voltage?

IF all the above check out OK and you are able to confirm a bad board the last ditch option for boards or cards covered in oil and dirt you may be able to salvage them. Wash them with warm soapy water (dishwashing detergent works well) using a soft paint brush rinse with clean water twice then rinse with alcohol and let air dry at no more than 100 F (about 72C ??)

Dan Bentler

Fortunately I've witnessed the machines working in UK & all documentation are available. The batteries & Program are intact. The machines are connected to correct power source. I think cleaning with soap water, IPA & drying may be best solution for startup

Regards
Jayesh

leitmotif · Sep 2, 2009

Well it is a good thing you saw them running in England.
You have verified that your power supply matches that used in England.

OK I just gotta ask
are you really sure you have them hooked up correctly?
Do you have plug type connectors between machine components?
I have made a lot of money off bad plug connectors.

I think I would check all sensors for free actuation and proper operation before I started cleaning circuit cards.

You may have a limit switch that is all gummy from dried oil / cutting fluid that is not operating and not letting machine run.

I know I recommended how to clean the cards but am not sure I am ready to recommend doing that at this stage.

Dan Bentler

Failure of electronic parts in old machines

Jayesh Shirpurkar

Member

leitmotif

Member

keithkyll

Member

leitmotif

Member

keithkyll

Member

James Mcquade

Member

Brian123

Member

Jayesh Shirpurkar

Member

Jayesh Shirpurkar

Member

leitmotif

Member

Similar Topics