Need to make a dead mans switch

@Eric
The OP is trying to avoid using a mains-powered relay and wants to use a 24VDC type.

@Bigal_scorpio

I reckon a N/C switch in the relays coil line would do the trick nicely

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It would. Or it could go in the relay's self-latching contact path as Eric mentions above.

What would be the maximum current available to the relay coil with the components shown?

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The spec for the Schrack 805024 relay you mention says the coil resistance is 475 Ohms. So the coil current is ~50mA. That means the bulb current also will have to be ~50mA, correponding to an 11W bulb or thereabouts. Perhaps as found in a fridge, microwave, night-light, sewing-machine....?

it was already turned on! WOW did it go!

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That would have been something to watch....from a safe distance!

Edit: A 100mA quick-blow mains-rated fuse in series with the bulb would be advisable, to protect the relay if the bulb should fail and arc over.
BTW, the wires going to the NC contacts of the relay aren't necessary (they were used in the simulation of the circuit and I forgot to remove them!)

Hi Guys,

Just another query, does it matter that the motor is induction?

This motor is a 1.4kW one that I have been given by a mates dad and I can't see any brushes but there is a huge starting cap on it, so I assume its an induction motor. Some relays seem to differ in the current they are rated at for resistive and induction loads. Is there anything I can do to help the contacts?

Al

Eric, Its nothing serious, just a dose of what the wife calls man flu! The neck is no better or worse I'm afraid. Al

does it matter that the motor is induction?

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It matters in that the relay contacts are rated 25A for a resistive load and the spec doesn't give a rating for an inductive load. However, as your switched load is ~ 6A the relay may be ok.

here's a BORROWED, modified drawing of how to hook up your relay, You could add a 24 volt zener across relay coil or a resistor to load the bulb for a voltage divider.
Kinarfi

You could add a 24 volt zener across relay coil or a resistor to load the bulb for a voltage divider.

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There's no need to do that; the coil resistance already forms a voltage divider with the bulb resistance and the resulting voltage across the relay is....24V.

Latching relay

I posted last week a simple relay switch with ON / OFF buttons on YouTube.

The OFF button can be replaced with a foot switch. Get a NC switch for that, when pushed the relay drops out, switches off the load.

The wiring is clearly shown in the video. For the control circuit use the 24 Volts instead of the 240 Volts used in the example

Look under my name RODALCO2007

can't attach link as I am on the work computer

https://www.youtube.com/watch?v=YZdO9v38KHI

Link of latching relay as promised.

The orange control wire needs to be supplied from the 24 Volts control supply and the return wire from the coil goes back to the 24 Volts circuit to maintain electrical separation of the control circuit and mains supply.