Universal machine motor issues.

[BenM]

Hi, I hope somone can give me a bit of advice.
I have a sicar universal machine, the power switch has three positions, 0,1 and AVV.
Normally to start any of the motors you have to go to AVV , the motor starts and the switch returns to the 1 position but a few days ago it started firing up as soon as it hit the 1 position. I've been told the AVV position probably gives a bit more current to the motors to help them start turning but it seems that I've possibly got a faulty relay but but more likely switch and it may be that its stuck on start up current. (the emergency stop buttons have stopped working as well)

Does this sound like a dodgy switch? Am I going to damage the motors if I use it?

I've found a replacement relay cheap enough but am struggling to find the same switch at any price.

Any advice would be appreciated.

 

[Markvk]

Can you give us some more information? Is it single or 3 phase? Do you have a wiring diagram, there should be one with the instructions.

It sounds like a star delta starter stuck in star..... that will give you a low start up current but less torque, about three times less I think... been a long time since my AC theory.....

It wnt damage the motor but you wont get the performance that your used too and it may stall under load

This is all guess work without more info though

Mark

 

[BenM]

Its single phase. My friend has three phase machines so I know a little bit about how star deltas start up and its not like that. It feels more like a car ignition, you turn the switch far clockwise to start then it springs back.
There is a wiring diagram. I don't understand it.
I had been continuing to use ithe machine and it seemed to function normally. I thought the AVV switch position was a safety thing until someone told me about start up current.

 

[Markvk]

AVV is common in cars but only acctuates the start motor and then springs back when you release the key to deactivate the starter motor.

Sounds like your switch does somthing similar but what? We would be guessing without the diagram, I suppose ith could be somthing to do with capasitor start / run switch capasitors in/ out but need the diagram

Mark

 

[Markvk]

Hi Ben,

Had a quick think and it is likely that you have a capasitor start/run motor, a different capisitor is used to start the motor from the one that runs it. The different capasitors will need switching in and out thats probably what this does.

Herers some info for you, you run the risk of over heating the motor etc


https://en.m.wikipedia.org/wiki/Motor_c ... capacitors

Mark

 

[Myfordman]

If the op would let us see the diagram them we might be able help instead of guessing.

 

[BenM]

Hi
Diagrams seem to be for different models, H210 or H300. Mine is H260 and the diagrams only appear to have one motor, mine has three. And I can't get the scanner working since I changed to Linux. I've had a good search online but can't find anything.
I've taken the switch off and taken it apart as much as I dare, cleaned it a bit but it didn't seem too bad anyway. No change.
There are some big capacitors in the machine, like the size of a can of red bull.

The wiki link mentions centrifugal switches but I guess the AVV position does that job.

 

[Myfordman]

Is it quite an old machine? Manual switching of starting capacitors went out of use decades ago in my experience.
I did work on one system where the running windings were split in two and connected in series to start and parallel to run.
That used a push button that had to be held in to enable the starting configuration and released manually once up to speed. A second conventional button released the contactors and stopped the motor.
It is written up in my motor paper referred to elsewhere on this site
This of course needed an unusual motor with three windings (Start, Run A & Run B)

Looks like yours has a fairly specialised switch and possibly only available from the makers or their agents
I'd have expected a switch with off, start and run in that order not as you have described.
With multiple motors, there will be a good degree of contactors and logic interlocks inside and to fully solve it, the correct diagrams will be needed

 

[BenM]

Its from the 80s. I've had it about a year and never had any problems.

I'll try and get hold of the diagrams.

Does it sound like the switch is the problem? Its made by Bremas and yes it appears pretty specialised, I can't see anything else like it.

Am I damaging the motor or capacitor running it as it is?

 

[BenM]

 

[Myfordman]

I'm thinking more of motors in the 50s using manual start systems. Since then virtually everything would have been fitted with a centrifugal switches other than potted refrigeration motors.
Bit of a mystery to me and I've been playing with motors for a very long time - 50 years ish.

I wonder if they have been trying to economise and using the same start capacitor for which ever motor needs starting.
Do all the motors start with equal ease since the problem started? I'd expect a planer and possibly the spindle to be more difficult to start than perhaps the saw?

As for damage then, unhelpfully, the answer is "it depends"!

If the motors are managing to start OK using just their run capacitor, then possibly not a problem.
If somehow the start capacitor is connected during run (as well as the run capacitor) then yes the motors will be drawing excess current and possibly overheating and could burn out.
However I would expect a professional maker to have included a thermal overload relay in the set up and this would detect the extra current and trip out hopefully within a few minutes to protect things in the event of both capacitors being switched in for extended periods.

Can you see how many capacitors (red bull cans!) are inside. There could be two and shared amongst the (three?) motors or there could be one run capacitor per motor and a shared starting one, or a start and a run for each motor.

Is the maker still going? Several other makers have machines with 260 in the name. Could it be a common design badged for different makers? Lurem is a possibility and they had single and multiple motor machines with 260 in the names.

OK just seen your photo. What is the Telemechanique thing at the top and what does the yellow plate do? Looks like two buttons but don't know why you need them. The rotary switches with off positions between the motors and the starting switch should be all you need? unless it is some Emergency stop/braking system perhaps.

 

[BenM]

All the motors seem to start as they always have.
I've had this problem for about a week. I don't know much about motors and had assumed the AVV position was a safety thing until a friend told me about start up currents this weekend. I had been using it last week with no problems.

There are two capacitiors. One has three wires, the other has only two, one of which is one of the three. Did I explain that well enough? The two capacitors are linked by a wire.

The other strange thing is the two emergency stop buttons cut the motor when they're held it but the motor starts up again when it is released. These worked fine previously.

The planer definitely has some thermal protection, I tripped it one day after a big planing session. It is on the motor and it took me quite a while to find it. I thought I'd fried it.

The yellow plate flips down and the nib on it pushed the red switch as it closes. You can them lock it if you felt the need.
I'm in France and it doesn't seem uncommon here for machines to have this kind of thing. My neighbour has a lot of pro three phase gear and I think they all have these kind of master switches.

Its a Sicar h260 i37
I think Sicar is an italian company who no longer exists, I now of lurem machines and this is different.

 

[Myfordman]

Possibly a confusing name but a thermal overload relay uses a thermal method to average current measurement over a longer period that a fuse would do.
If when the machine cut out after an extended session of work this might have been something on the motor which actually sensed its temperature.

You did not tell me about the two buttons on the telemechanique box. I can just see one is red is (was?) the other green.
Do you have to push this first before starting using the switched marked AVV?

Please remember you have this machine in front of you and know how it works - I don't have that benefit lol.

A big clue is that it restarts when the estop buttons are released. That is wrong and unsafe. That implies that the start switches (either the green button) or the spring return bit of the AVV is not opening when released. Investigate that and it might just sort the rest out

 

[BenM]

The two buttons were red and green. They work in so far as they turn the machine off and on. I assumed it was also an NVR switch but I just tried it with the motor running. Red cut the power and green started it again, the motor stated up again on its own. I don't think I ever tested it as an NVR previously. I didn't really use these buttons, I have a master switch in my workshop for the sockets and I use this.
I suppose the AVV worked as an NVR which is why I assumed it was a safety thing and not an electronics thing.
I'm not sure how much of the stuff in the plastic box is original, the relay looks newer than the rest.
Its a TELEMECANIQUE LC1 D09 10.

My feeling is that the switch is the culprit, I started taking it apart but it looked very complicated. Maybe I'll try again tonight.

I've just started a little woodworking business and I've found a nice little niche, I've got several outstanding orders so I'm scared I mess up the switch and can't work while waiting for an expensive replacement switch that I'm not even 100% sure is actually the problem.

 

[Myfordman]

OK well it is up to you where you go from here. My advice for what it is worth is getting the NVR function working (even if it turns out to be something to do with your AVV switch)

I'll pull out now as you clearly know what you want to do.

 

[BenM]

I'm taking your advice!
I didn't use the NVR buttons, so that just leaves the switch.

 

[beech1948]

https://www.google.co.uk/search?q=T...&gfe_rd=cr&ei=Tsr6VqSKCM7DaPy9hqAH&gws_rd=ssl

The above link gives you a Google list of sellers and info re the Telemechanic Lxxxxx box which appears to be a relay + contactor + switch. You will see a few pictures of similar devices. These may or may not be identical to yours but a further look at the device you haver will provide better info re part no LC10910 and G1 to G9 types.

The lucky part is that your contactor/relay is still being manufactured and is readily available around the world

If you look for the same on Youtube you get a list of descriptions of this device by types, how a contactor or relay works and even how to wire it up with stop/go switches.

Try to remove the front of the switch box and look for a part no. Read the manuals you have to see what devices these have in circuit. If electric circuits are not your thing then see if a mate cqan scaqn them and put hem up here as this will give us all useful info.

Its worth trying to find out if the orginal manufacturer of the device is still in business as they can usually give accurate advice/descriptions of their old stuff if your lucky.