Mortiser Elec fault

[quintain]

**** all
I attach a bunch of pics.
Can this mortiser be updated and run from 1 phase 13 A socket.
It has to date run from a 13A socket but the original on/off box has broken some contacts.
I bought ot 2nd hand about 20+years ago and it was converted to a 13A supply, I have only ever used it with 13A plug and socket
It will start and run when connected to a 13A socket but it was not switching off by the use of the onboard "Red button"
Can anyone advise me please.
BTW I do not know much about electronics but I am a careful & safe worker.

 

[Amplidyne]

If the motor runs, you have a good start. (Pun not intended)
The "stop" buttons, both the one on the starter itself (assuming it has buttons) are normally closed, and are in series with the coil. The start button in normally open and in series as well. The "hold on" contact, is across the start button. There's also an overload contact in series. They vary on how exactly this is physically done. So it sounds as if the button is stuck somehow, or it's not wired in.

When you push the start, it energises the coil, and the hold in contact closes across the start button. When you want it to stop, you press the stop button which opens the coil circuit.

"Some broken off contacts" sounds ominous. They're quite easy to make inoperable.


I assume you have a meter. Use it on the ohms setting to check the continuity of the circuits.


I must say, as always, unplug it and check that it's isolated before doing anything. And watch that capacitor, they can store charge.

 

[Spectric]

Do you want to keep it looking original ? If not then the best solution is to just buy a new direct online starter (DOL) and replace the original but ensure the overload is correct for your motor.

 

[Amplidyne]

ETA I made a mistake and quoted myself. Meant to quote Spectric about getting a new starter.

His idea is by far the best option IMO.

OP you want a unit with a 230V AC coil.

All the decent ones I've come across have three phase overloads. Basically you wire it so the motor load goes through all three in series. It shows you in the instructions assuming it's new.

 

[Dabop]

I'm not seeing the 'red button' anywhere- is it on the motor itself??- because if so thats probably an old red thermal overload cutout reset button, not the off button...
eg

I am also seeing what might be old VIR cables in there- in which case, that REALLY should also be replaced (in pic 4, looped in front of the power cable on the left of the control box), plus generally the wirings quite a mess...

 

[Dabop]

And can you take a clear pic of the writing on the 'metal box' sitting on the timber- that appears to be your capacitor!!! and I haven't seen that style used in decades- if it is, its probably so dried out, god only knows what value is at (and the two terminals on top are live whenever its plugged in- there should be a cover on them)
Looking at the wiring on the 'control box' ie top open box in pic 4 again- its hard to tell exactly whats happening there from the picture- but it 'looks' as if there are no switches inline at all, and someone has 'jerryrigged' it to run whenever it is plugged in and switched on- in which case its running correctly 'as wired' (but obviously not safe like that)

 

[Dabop]

With these motors you really don't need the 'start button and stop button' control box (DOL)- the simple old fashioned 'latching single emergency switch/ on/off' ones work perfectly well (and are a lot more reliable)

These usually have an arrow on them, like this...

Look for 'latching' rather than 'momentary contact' or NC/normally closed- to start the motor, pull it out and twist in the direction of the arrow, to stop- just hit it...

No contactors or relays, just a simple mechanical switch (they don't work on motors with a 'dual capacitor' arrangement ie a start capacitor and a run capacitor' but yours appears to be the simple old fashioned single cap 'run capacitor' only variety as are most motors)- you can considerably reduce the amount of cludged up wiring in there- fit a new power cord- (looking closer, that suspected VIR is the main power cable in!!!) and a general tidy up is definitely advisable...
Yours (some clearer pics would be a good idea to confirm it, but pic 6 seems pretty clear it is the 3 wire version- the earth wire doesn't count here lol) appears to be the three wire version top right...

compare to pic 6

In which case it would be wired like this with your colours

(the black joiner in my diagram up the top is the existing black 'BP' screw connector hanging out on the right in the 'control box in your original pic 4- which goes on down to what I suspect is likely a very dried out capacitor sitting on the wood block at the bottom...)

I would get some Wago connectors (originals, not the cheap Amazon/Ebay knockoffs)- fit a new powercord (if it is indeed VIR as I suspect- it is likely in VERY poor shape and extremely dangerous and could short internally if bent or flexed!!!) and disconnecting one wire at a time- replace that old BP connector with a Wago, then wire it with the new switch according to the diagram (them using all brown wires doesn't help grrr)

If you can get a clear shot of the markings on that suspected capacitor, a replacement for that is advisable as well (if it has dried out and changed in value, it could cause the motor to run hot, have reduced power and possibly damage it even!!!)

This thing...

It likely has a number (probably somewhere between 50 and 150 with MFD after it- that is the old fashioned marking for microfarads or uF- get a modern replacement rated at 400v or higher with the same number in uF

This is one I was working on earlier for a mate interstate lol
His original (80uF marked as 80MFD)

and the replacement...

He had been searching for hours for a 80MFD one, and couldn't find one- not knowing that that was just the old way of writing 80uF's lol- he had been looking at literally hundreds of suitable replacements and ignoring them because they didn't say MFD...
(he's a nurse, not an electrician lol- I go to him for medical advice, he comes to me for the 'sparky stuff' lol)

 

[quintain]

If the motor runs, you have a good start. (Pun not intended)
The "stop" buttons, both the one on the starter itself (assuming it has buttons) are normally closed, and are in series with the coil. The start button in normally open and in series as well. The "hold on" contact, is across the start button. There's also an overload contact in series. They vary on how exactly this is physically done. So it sounds as if the button is stuck somehow, or it's not wired in.

When you push the start, it energises the coil, and the hold in contact closes across the start button. When you want it to stop, you press the stop button which opens the coil circuit.

"Some broken off contacts" sounds ominous. They're quite easy to make inoperable.


I assume you have a meter. Use it on the ohms setting to check the continuity of the circuits.


I must say, as always, unplug it and check that it's isolated before doing anything. And watch that capacitor, they can store charge.

Thank you Amplidyne
I show another pic, where I try to show what is (your comments on my words "Some broken off contacts"). It is what I would call the release bar i.e. the bar that is operated by the Red OFF button.. I welcome any/all advice on how to connect 13A supply into the top of the motor wiring and dispensing with all original switch boxes...I have no wish to keep the machine in its original state, I just want it to Start-Run-Stop.

 

[Against_The_Grain]

I have one of these exactly like this, they are a little more tricky to work on because of the external capacitor. I would strongly suggest not to change anything unless you really have to. I can take the cover off mine if you need a photo of an operational switchgear as an aid.

I would first look to see if the stop button on the cover plate actually engages with the stop switch inside the box correctly, these switchgears are inherently simple and built to last forever, it's very rare that they fail.

 

[Dabop]

I have one of these exactly like this, they are a little more tricky to work on because of the external capacitor. I would strongly suggest not to change anything unless you really have to. I can take the cover off mine if you need a photo of an operational switchgear as an aid.

I would first look to see if the stop button on the cover plate actually engages with the stop switch inside the box correctly, these switchgears are inherently simple and built to last forever, it's very rare that they fail.

They really are quite simple to work on- and at least some of the wiring in there (specifically the actual power cord from the plug) looks to be VIR (Vulcanised Indian Rubber) which is extremely dangerous to still be using, and should be replaced immediately...

The old wax sealed 'tin capacitor' sitting on the wood at the bottom (I strongly suspect it is a cap) is also likely well off its rated value by now- and has likely dried out- if so, it should also be replaced with a new one (caps really should be replaced (or at least measured) every ten years or so for older ones, a modern one at twenty years- if they 'dry out' and change in value- your motor will probably still run- but much hotter in the windings than it should (with possible damage or even destruction resulting), and its output power will be down as well... A replacement is only about $15-$30Au here and readily available...

 

[Amplidyne]

Thank you Amplidyne
I show another pic, where I try to show what is (your comments on my words "Some broken off contacts"). It is what I would call the release bar i.e. the bar that is operated by the Red OFF button.. I welcome any/all advice on how to connect 13A supply into the top of the motor wiring and dispensing with all original switch boxes...I have no wish to keep the machine in its original state, I just want it to Start-Run-Stop.

Sorry but at the moment it just looks like a mess. All the makes of starters are slightly different internally, and it looks like the wiring has been messed about with.
Personally, I'd get a new starter with start and stop buttons on the front as Spectric says. Generally although they're pretty reliable, you get the occasional broken one, and the easiest / only repair is replacement.

Replace any VIR cable, and replace the capacitor as already said by dabop.

Make sure no live terminals are left uncovered like they are with the capacitor at the moment.

Honestly the simplest answer is usually the easiest.

 

[Dabop]

Not a fan of the DOL switches- more complicated and less reliable than the older 'mechanical pull and turn' latching ones...

The cheap ones in particular are VERY hit and miss regarding reliability...

(normal switches are a no-no here, as you need an 'emergency stop' style "slap at it wildly" switch here- the latching mechanical ones I showed earlier meet the requirements for on/off as well as emergency stop, unlike a 'toggle' style switch (some DOL style on/off buttons although red for off, also don't meet the emergency stop requirements here as the off button on some doesn't stand proud out the surface...)
And yeah- I hope that cap hasn't been running like that!!!

 

[Amplidyne]

Not a fan of the DOL switches- more complicated and less reliable than the older 'mechanical pull and turn' latching ones...

The cheap ones in particular are VERY hit and miss regarding reliability...

(normal switches are a no-no here, as you need an 'emergency stop' style "slap at it wildly" switch here- the latching mechanical ones I showed earlier meet the requirements for on/off as will as emergency stop, unlike a 'toggle' style switch (some DOL style on/off buttons athough red for off, also don't meet the emergency stop requirements here as the off button on some doesn't stand proud out the surface...)
And yeah- I hope that cap hasn't been running like that!!!

The thing is that as it's not a fractional horsepower motor (don't know what the regs say now, but IIRC it used to be that) for something like a fan, then it must be fitted with a starter that gives no volt release.
I'd fit any workshop kit with a no volt release.
That is if the power goes off, the starter will drop out and needs a button pressed to start it again.
It's also sensible to have overload protection.

Don't want to sound po faced about it, but them's the rules at least here in the UK.

The type of switch you are describing is simply meant as an emergency stop button, to be used in a control circuit. Not as a motor starter.

I'd get a decent starter. . .

 

[Dabop]

The thing is that as it's not a fractional horsepower motor (don't know what the regs say now, but IIRC it used to be that) for something like a fan, then it must be fitted with a starter that gives no volt release.
I'd fit any workshop kit with a no volt release.
That is if the power goes off, the starter will drop out and needs a button pressed to start it again.
It's also sensible to have overload protection.

Don't want to sound po faced about it, but them's the rules at least here in the UK.

The type of switch you are describing is simply meant as an emergency stop button, to be used in a control circuit. Not as a motor starter.

I'd get a decent starter. . .

Not a requirement here (yet, but likely coming) however that doesn't apply to already existing equipment (especially that is not used 'commercially')) they only have to meet the regs that applied at the time of construction (and THAT does apply in the UK currently)
Considering the state of that machine currently, I seriously doubt that it would meet any current regs (or even basic safety inspection)
And yes the switches I linked to earlier ARE 'starting switches' and not just 'emergency off' switches- you can readily tell the two apart- there is no latching mechanism on the 'emergency' switches, while there IS a latching system on the 'emergency/power' combination switches- you can visually tell then apart by the arrows on the 'big red button'...

To turn on, pull out and turn...
To turn off hit the button...
In an emergency- scream and slap at it lol...

As opposed to a non latching 'emergency' N/C switch in a DOL- which has no latching mechanism... and is 'push in only'

DOL's have been a source of many equipment failures in my experience- ESPECIALLY the cheaper ones... (but even the more expensive ones have a much higher failure rate than the old mechanical style power switches)

 

[Spectric]

@Dabop looking at your drawing I never thought about wiring colors in Australia but are you still on the old british colors of Red and Black ? Then Red, Blue & Yellow for three phase with Blac as the neutral ?