HELP!! Wiring madness

[BevelParticipant @bevel]

Hi All,

 

Fitted a single phase motor to an old surface grinder I have and it runs great. However prudence dictates I fitted an emergency stop button and this is where I’m up against it.

Bought this switch and I have no idea how to connect it so throwing out to my friends on the forum to guide me home lol. Some of the vids I’ve watched the switches only have 8 connections where this one has 12, presuming its down to the magnetic side of things. So basically I have 220V going in and out and need simpleton instructions on how to connect?

I’m competent in nearly all areas of engineering/construction but electrics is something beyond my scope of expertise I’m afraid so your help is greaty appreciated as always.

Best regards to all

 

[Andrew TinsleyParticipant @andrewtinsley63637]

Ask the supplier for a wiring diagram. This should be included as standard.

Andrew.

[Robert Atkinson 2Participant @robertatkinson2]

Hi Bevel,

Good to see that you are trying to do a proper job.
Do you have a contactor or relay in your circuit? The switch box you have bought appears to be intended for a control circuit such as a VFD or contactor.

Are there any markings on the switch such as a current rating or part number. The E-Stop may not be capable of crrying the motor current which is not ideal. It appears to be a latching control switch rather than a power braking type E-Stop.

Robert.

[Andrew Tinsley]

On Andrew Tinsley Said:

Ask the supplier for a wiring diagram. This should be included as standard.

Andrew.

The supplier of a set of switches is not going to provide a wiring diagram. They have no way of knowing what you are conneting it too.

Robert.

[Ex contributorParticipant @mgnbuk]

The switch contacts look to have a standard marking – first digit is the contact number, second digit denotes contact type where 1-2 is normally closed and 3-4 is normally open.

So of each switch’s contacts one is normally open and one is normally closed. A few seconds with a multimeter will confim this.

HTH

[BevelParticipant @bevel]

Hi Gents,

 

Typical I waited a fortnight as I unknowingly bought from a chinese supplier posing as UK based and now it might be wrong one anyway 🙁

I honestly thought a cut-ff switch was a cut-off switch but in hindsight I should of asked here first, noob mistake!!

This is all I can see on the terminal blocks

[BevelParticipant @bevel]

 

Did run multimeter over contacts last night and found contacts 11 + 12 have continuity which stops when button pressed and continuity then at 23/24.

I thought logic would prevail and i could work it out but the magnetic side of things threw me all a kilter lol

[Robert Atkinson 2Participant @robertatkinson2]

Hi,

10 amp contacts so should be OK to break the live for the emergency stop.
You still need a relay or contactor to provide the Start – Stop and No-Volt Release functions.
What power is the motor? Knowing this I can suggest a suitable relay or contactor.

Robert.

[BevelParticipant @bevel]

Hey Robert,

 

Thanks very much, motor I fitted was 1hp/.75kw.

 

Do you think it better if I just get a different switch as you can see I’m quite the novice when it comes to electrics or would it be straight forward?

[BazyleParticipant @bazyle]

A no-volt release is really only going to activate if there is a second or more ways of turning off the power eg with interlocked safety shields, foot bar, overload/overheating trip. It is, I hope, not like you walk out of the shed with it still running and flip a main power breaker as you close the door.
So you may only need to wire in the big stop button so that when you twist and release it the motor runs and when you hit it the motor stops. When not in use unplug at mains socket as a stranger in the shed might think it needs to be released and then the other buttons used. (remove or cover the extra buttons.

NVR relay switch units come in two forms, looking almost identical. You want if possible the rarer  type that have auxiliary connections to  add in additional stop switches so that you can in future add a safety shield interlock.

[BazyleParticipant @bazyle]

And it turns out I have one of each that I can actually find on my desk!

The extra pin on the one on the left has to be connected through your interlocks and safety switches, lots of them in series, and then to live. All such swicthes then have to be closed to allow the relay to power up and any one breaking drops the relay power.

[Martin of WickParticipant @martinofwick]

Bevel,

The switch box you posted does not appear to have an NVR component.

google NVR + E stop switch should come up with a nice yellow box with on and off switch plus a big red button, available form the usual suspects for anywhere between £15 to £20.

eg,  Lathe NVR (No Volt Release) Safety Switch & Stop Emergency Stop 220/240v DP | eBay UK

Connect Neutral to the on/off/NVR poles in the usual way then take the Live connection from plug side and wire E stop in series to the on switch/NVR Vin pole. the live Vout goes to the motor. If there is a choice, use Normally Closed switch connections on the E stop when big red button is in the up position.

[BevelParticipant @bevel]

 

Thanks for your input Bazyle very interesting. I can’t believe there’s so much to it rather than just fitting a simple switch.

[BevelParticipant @bevel]

 

Cheers Martin that should save some faffing.

 

Guys you been great once again and big thanks to you all

[Les Jones 1Participant @lesjones1]

What is the original switching arrangement as you have not given any information about that ? If it is a normal contactor (With or without Thermal overload trips.) then adding an emergency stop button is easy. The unit that you have bought is just the start, stop push buttons and the emergency stop button. It will not work without a contactor.
I think the emergency stop button should be mounted where it can be operated by your knee if your hands become trapped.

Les.

[Andrew TinsleyParticipant @andrewtinsley63637]

Robert,

It depends on what the description of the device was. If it is sold as an NVR/ emergency stop switch. Then it SHOULD have a wiring diagram, either enclosed with the unit, or available from the supplier.

So how was the unit advertised? Maybe the O/P purchased it because it had an emergency stop button and did not realise that it was NOT an NVR/ emergency stop unit?

There are plenty of NVR / emergency stop units on Ebay etc. The ones I have purchased have come with full wiring instructions. The particular unit in questions does not seem to have even the basic information available (e.g. current rating). A case of buyer beware!

Andrew.

[noel shelleyParticipant @noelshelley55608]

The wiring of the switches should be simple enough BUT the contactor is not there nor is there any NVR or overload. If you are buying an overload device with or as part of the contact assembly check first that you know the FLA , current drawn in amps by the motor and stated on the spec plate. The start button will be N/O the stop and Estop N/C . This is a simple circuit and there are many complicated one for clever applications. Good luck.  Noel.

[BevelParticipant @bevel]

Uxcell Push Button Switch Box Momentary NO NC Red Green Switches and Emergency Stop

1 review
|ID:1075331

Specification
SKU
a19070800ux0112
Material
PC
Emergency stop switch
Self-Locking
Contact type
NO NC
Button color
Red, Green
Ith
10A
Ui
415V
Screw hole dia
4mm / 0.16 inch
Button hole size
22mm/ 0.86 inch
Outlet hole diameter
20mm/ 0.79 inch
Total size (approx)
150 x 71 x 91mm / 5.91 x 2.8 x 3.58″ (L*W*T)
Brand
Uxcell
£13.00Regular price

35%OFF
Order 3,750+
− +
In stock, dispatch in 24 hours.
Inquiry Now
Default Title – £13.00 GBP
Free Shipping over £15
Description
Description:

The push button switch station consists of three switches, one is a momentary red push button switch, one is a momentary green switch and a emergency stop switch.

Can be widely used to control the electromagnetic, contactor, relay and other automatic control electric circuits.

Comes with quick connect terminals to allow for fast connections.

 

Specification:

Material: PC

Red Green Button: Momentary

Emergency Stop Switch: Self-Locking

Contact Type: NO NC

Button Color: Red, Green

Ith: 10A; Ui: 415V

Screw Hole Dia: 4mm / 0.16″

Button Hole Size: 22mm/ 0.86″

Outlet Hole Diameter: 20mm/ 0.79″

Hole Distance(center to center): 115 x 54mm/ 4.53″ x 2.13″ (L*W)

Total Size (Approx.): 150 x 71 x 91mm / 5.91 x 2.8 x 3.58″ (L*W*T)

 

Package Content:

1 x Push Button Switch Station

[BevelParticipant @bevel]

That was item description gents, I just didn’t take a punt it all looked kosher. Company is called Harfington but little did I know iitem was to be shipped from China. I have no issue with chinese products my workshop is full of them but it did take longer to arrive than expected

 

[Bazyle]

On Bazyle Said:

A no-volt release is really only going to activate if there is a second or more ways of turning off the power eg with interlocked safety shields, foot bar, overload/overheating trip. It is, I hope, not like you walk out of the shed with it still running and flip a main power breaker as you close the door.
So you may only need to wire in the big stop button so that when you twist and release it the motor runs and when you hit it the motor stops. When not in use unplug at mains socket as a stranger in the shed might think it needs to be released and then the other buttons used. (remove or cover the extra buttons.

NVR relay switch units come in two forms, looking almost identical. You want if possible the rarer  type that have auxiliary connections to  add in additional stop switches so that you can in future add a safety shield interlock.

Not correct. You are conflating NVR and Emergency Stop Functions. A NVR stops the machine restaring without warning after a power interruption when power is restored. It’s not just about turning the power off at a master switch. It’s about a short break in power, user reaches into danger zone to investigate and machine re-starts. On a conventional systen using buttons such as Bezel has the NVR is provided inhernetly in the contactor function. An E-Stop is a means to stop the machine in an emergency. A good E-Stop design wil work independently of the stop / start controls.

The combined Stop / Start control and NVR you show would be suitable for Bevels application but is not what he has. On the seperate coil connection version, the coil connection is for interlocks (chuck guards, door switches) not emergency stop functions. It won’t stop the machine if the contact welds for example. If used the coil connections to the interlocks MUST be in the neutral not the live. If you don’t do this the interlock circuit will be live with the machine stopped representing a serous shock hazzard. It is dangerous to provide advice on saftey critical circuits if you don’t fully understand the requirements. Also applies to Martin of wick’s omments.

I assume there may be incorrect information about this on the internet for it to be commonly stated.

Robert.

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Bevel, back in 2007, I refurbished a small hobby drilling machine, which was my fathers, when he had it in his shed back in the 40’s / 50’s, it was powered by a line shaft, which also drove his lathe.

However, I decided to make it as a portable bench drill as can be seen above, I didn’t include an emergency stop for it, but one could be added easily enough, but it does include a NVR circuit, a missing guard situation and a thermal cut-out, should the motor overheat. Your switch box could be used quite easily with a similar circuit using a contactor, as shown below, but you may not need the thermal cut-out.

The circuits below show all the states they can be in.

As you can see, the stop is on normally closed, and the start is on normally open, an emergency stop could be put in the live feed, or after the start switch, before or after the stop switch, and using the normally closed contacts. Hope this is of help.

Regards Nick.

[BevelParticipant @bevel]

WOW how knacky is that drill press, love it!

Amazing I bet thats comes in handy Nick.

Thanks for the info lovely job.

Regards,

Nick (SNAP! thats me also lol)

🙂

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Bevel, yes it’s very useful for drilling small holes. But I did have to make a new drilling shaft and top bearing, as the old shaft was very bad rusted, and the top bearing missing altogether, the original chuck was also long gone.

Here’s a photo of my father using this drill back in the 1940’s.

Regards Nick.

[Les Jones 1Participant @lesjones1]

The description that you posted at 09:52 on 9/5/26 describesthe item that you show in your pictures. It does not claim to be the complete power switching solution. If you provide details of your existing power switching then there is a good chance that one of us can advise on adding it into that.

Les.

[Martin of WickParticipant @martinofwick]

Robert,

I tend to agree with you in respect of connecting neutral rather than live for switching through an EStop, especially if  a whole bunch of additional interlocks are being daisy chained via external circuits.

However, in the case of this single integrated NVR EStop unit, the rest of the world including the manufacturer seem to think that the live should go through the EStop. I genuinely wonder why that is?  Is the risk really significantly higher for a simple integrated switch box?

Who am I to gainsay the manufacturers/suppliers wiring advice? I will try to find the piece of rice paper instruction that came with the unit to post.

I have used one of these simple integrated switch units to replace  the old switch to a .75 kW lathe motor (was assuming the OP in similar circumstance and wanting something simple). You may be amused (or not) to know that the switch replaced was an ancient ornate round brass 1940s style light switch, complete with decaying wiring! So I had rather hoped for a modest reduction in risk, seemingly not it appears.

[Author]

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