Wiring for a emergency stop switch

[jamman1125]

Hi guys, its me again! Back with another quiz to solve.

I recently purchased an emergency switch from china to be used on my homemade table saw. However I want to ensure I have the right idea of how to wire it up.

I have made a diagram of how I think it should be wired based on my electronic knowledge (limited) but if its wrong please let me know how you would go about wiring it instead.

Here is the diagram:
Obviously brown is live, blue is neutral, green is ground.

The bottom white wire is mains input and the weird drawing attached to the top wire is just a single mains plug (female) where my table saw will be plugged in.

Also here is a picture of the front of the unit to get a better idea.



Many thanks!!

James

 

[Minder]

Are they all momentary or is any one maintained?
Typically that P.B. station is used in conjunction with a relay or two, particularly if they are all momentary type.
In the case of just one simple tool just two buttons are needed, start/stop.
I could not load the diagram book due to file size but just google ON/OFF p.b. wiring.
M is a relay that turns the motor on
Without the relay you would need the maintained type button..

M..

 

[Minder]

The bottom E-stop appears to be a push stop-turn release, so conceivably you could just use this one only if it is capable of carrying the table saw current but generally limited to 5a or so..
M.

 

[hevans1944]

The type of switch you have shown appears to have momentary NC (Normally Closed) contacts, labeled 1 and 2, for the "0" or OFF switch, and momentary NO (Normally Open) contacts, labeled 3 and 4, for the "1" or ON switch. It requires a relay (or contactor) as @Minder indicated in his post #2 wiring diagram to operate the motor. The NC contacts labeled OL in his diagram are optional, but are usually an integral part of a motor-controller which you apparently do not have. Your motor would be wired in parallel with "M" if the switch contacts are rated for sufficient current... always problematic when purchasing Asian products. The safest procedure would be to use a separate set of separately fused contacts on the relay or contactor to connect the motor to the mains supply. Remember, the purpose of fuses is to protect the wiring. Fuses are not intended to protect equipment, such as your saw motor, from overload conditions.

What is the purpose of the red, round, serrated-edged knob with NC (Normally Closed) contacts, labeled 1 and 2? If this is an emergency stop (E-STOP) button, then wiring it in series with the middle "1" button would be acceptable whether or not this button latches in the open-circuit position, provided a relay is used as shown in @Minder's wiring diagram. Be aware of the electrical current limitations of typically 5A as @Minder mentioned in post #3.

The wiring diagram in post #2, requiring a SPST relay and overload NC thermal cut-out contacts on a motor starter, is the conventional and recommended way to wire motors operating dangerous equipment. If you choose to wire your saw motor as you have shown, without a relay or contactor, and the button-operated switches are momentary switches, your saw motor will run only as long as you hold the "1" or ON switch pressed... hardly a recommended procedure for woodworking.