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Tef9
24-01-2023, 04:38 PM
HI there,

I am looking to use a contactor, I have several but I want to be able to power/energise them from Mains.

I found this (https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ebay.co.uk%2Fitm%2F19539907 3412%3Fmkcid%3D16%26mkevt%3D1%26mkrid%3D711-127632-2357-0%26ssspo%3Dbap--a-2t-y%26sssrc%3D2349624%26ssuid%3Dl97HHjUhRPS%26var%3D %26widget_ver%3Dartemis%26media%3DEMAIL&data=05%7C01%7C%7C4e0f8ea89a294e9e2f9208dafe20ba9f %7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C6381 01713759454908%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4 wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6M n0%3D%7C3000%7C%7C%7C&sdata=kFt228qa9z16Khavr%2BlPGcC19Es5rxrJhTM2KWdZ6w 4%3D&reserved=0)on ebay will it work with mains or will it need a 24v psu to energise it?

Best regards,

Andrew

m_c
24-01-2023, 11:25 PM
It states the coil is 220/240VAC, so should work direct from the mains.

Tef9
27-01-2023, 08:48 PM
It states the coil is 220/240VAC, so should work direct from the mains.

Thanks for the reply, I see from the diagram you simply connect the A1 and A2 to mains and L1 and L2 to the same feed. Then when switched on, you have power. I take it earth is just placed at the com earth point and does not go through the contactor?

Best Regards,

Andy

m_c
27-01-2023, 10:55 PM
Protective earths should never be switched.

I'll also mention that in terms of control circuits, any operator controls should be low voltage (IIRC sub 60V), with the common standard being 24VDC.
Things like push buttons should never be at mains voltage (there are exceptions, but in terms of commercial equipment, controls should be low voltage)

Tef9
28-01-2023, 12:06 AM
Thank you for the reply, this is a rough diagram of what I am trying to do.

Its taken ages to get this far, the socket will be removed and the mains will go to the RCD. 31683

The problem I was having was the DMM drives were taking too much with the spindle. So having contractors should be a good solution and is recommended by DMM.

Br,

Andy

m_c
28-01-2023, 12:35 AM
As you've already got 24VDC, I'd use that to control any contactors, and have the 24VDC PSU hardwired (via a fuse) to your main power switch.

Tef9
28-01-2023, 01:47 PM
Hello M_C

Thanks for the reply, I need 24v to get to the MASSO - this does not need a contactor per say, and can live without one. Can I use any contactor with 24v or does it have to state that 24v will work?

Br,

Andy

Tef9
28-01-2023, 05:32 PM
Hello,

I created this drawing - do you think this is a better way of doing this.

I Don't want to get it wrong and zap myself, the components or set fire to the garage.

Br,

Andy31684

m_c
28-01-2023, 09:14 PM
It depends on what you're actually using the contactor for.
If it's solely to control the main power, so you can use a smaller main switch, then it won't really matter what voltage controls it.

However, if you're using it as part of the E-stop, it should really be 24V.



You need to select a contactor with the correct coil voltage.