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How to connect 240v Mains to a relay safely

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SimonW

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Dear Friends,

I am familiar with ratings, pinouts, back emf and how to drive a relay.

My question is how would I safely connect 240v Mains to a relay?

Obvious way would be to solder a flex directly to the contacts, (the pins on the relay are not strong and has no big surface area to solder to.

If I solder the relay to a strip board I am scared of a fire hazard.

Do they make wire ended relays, then I can simply use a terminal strip

Any precautions I should use Fuse etc?
 
The optimum connection method will depend on the current the wires will have to handle, hence on the wire gauge used.
 
What is the rating of the relay contacts?

How much load are you trying to switch?

Do you have a part number or datasheet for the relay?

I think we need a bit more information in order to give a good answer.

JimB
 
Sounds to me like you need one of these or these.
The first one mounts on a DIN rail or panel backplane. the second solders onto a PCB. Make sure to get the right pin configuration.
I have soldered wires to relay pins on the 14pin icecube relays. its a PITA but can be done, make sure to shrink wrap.
 
All the 240v relays I've seen come with a mounting socket that has large spade , solder or screw terminals.
 
I was talking in general, I have quite a few of these spare:

**broken link removed**

(40.315) MAX switching is 10A 250v single pole

I will be switching max 6A using 2 core flex **broken link removed**

I understand that what I will be using will be of the PCB mounting, as these are nice a cheap..... I am aware that there are relays which have sockets with them, but this costs a alot more.

I hope this clarifys things
 
If the relay is PCB mounted then its pins need to be soldered to pads connected via tracks to a terminal block suited to the wire gauge used. The track width should be as large as necessary to carry the anticipated 6A current and any tracks at 250V must be isolated by an at least 3mm gap from other tracks/conductors.
 
also check
**broken link removed**

if you use relay, make sure to read datasheet carefully and derate contacts accordingly (depends on type of load too, rating is not the same for AC or DC loads, it is different for inductive loads and depends on voltage etc.). if you are not comfortable with this or have any doubts, oversize it or use contactor. contactor is just a special version of a relay (bigger, designed to work with higher voltages, larger loads, has force guided contacts, designed for inductive loads etc.).

on relay 10A is not always 10A. this is merely class of device. actual info on relay rating is buried in the datasheet.
for example on your relay breaking capacity drops to max 0.12A if you are using it to switch DC at 220V. that is 80x less than "10A"
for single phase AC motor running on 230VAC, this relay is good for max 0.55kW or 550W which means only 2A.
beware of 'AC' ratings too, you need to become aware of differences between AC1 and AC15 mentioned in the spec.
 
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