DC relay coil...

[Bob Engelhardt]

I have a DC relay with the coil connections marked \"+\" & \"-\". Does it
matter? The relay operates with either polarity so there is no internal
flyback diode. It\'s a 24v, 33ma coil for those who want to know.

Thanks, Bob

 

[Tom Biasi]

On 10/19/2021 11:08 AM, Bob Engelhardt wrote:

I have a DC relay with the coil connections marked \"+\" & \"-\".  Does it
matter?  The relay operates with either polarity so there is no internal
flyback diode.  It\'s a 24v, 33ma coil for those who want to know.

Thanks, Bob

If the designers marked it, probably would be good to follow that.

 

[Bob Engelhardt]

Yeah ... I guess what I was really wondering was why they would do that.

> If the designers marked it, probably would be good to follow that.

 

[Sjouke Burry]

On 19.10.21 21:33, Bob Engelhardt wrote:

Yeah ... I guess what I was really wondering was why they would do that.

If the designers marked it, probably would be good to follow that.

they should do that if a built-in diode is present.
Also, the plus and minus identify the coil pins.

 

[Tom Biasi]

On 10/19/2021 4:26 PM, Sjouke Burry wrote:

On 19.10.21 21:33, Bob Engelhardt wrote:
Yeah  ... I guess what I was really wondering was why they would do that.

If the designers marked it, probably would be good to follow that.

they should do that if a built-in diode is present.
Also, the plus and minus identify the coil pins.

They may use that package to make units with the diode.

 

[Bob Engelhardt]

I Googled it (like I should have in the first place). There are a
couple of reasons that a DC relay may be polarized:
- internal flyback diode (as mentioned)
- an internal LED indicator
- a permanent magnet used to augment the mag field
- in a latching relay

My relay does have a LED indicator, so that\'s what I\'m assuming is the
reason for my polarization. And not a permanent magnet.