Timer relay help

[coopersim]

Hello

I'm after a bit of guidance with this relay diagram

Will it be possible to use this to power a device after the primary source has been removed?

Example being power from flow switch removed, relay maintains power to device for x minutes after.

 

[JohnW2]

Will it be possible to use this to power a device after the primary source has been. removed? Example being power from flow switch removed, relay maintains power to device for x minutes after.

I don't think it's the right device for that - I think it would probably work 'back-to-front' in comparison with what you want. From what I can make out of the documentation, if you supplied it continuously with the output of a flow sensor, the power to the switched device would remain 'on' for the first "x minutes" of output from the flow sensor, whereupon it would be switched off, and would remain off until the flow switch output ceased and then reappeared again!

Kind Regards, John

 

[Echo the husky]

You want something like this with a delay off.

 

[Simon35]

Hello

I'm after a bit of guidance with this relay diagram

Will it be possible to use this to power a device after the primary source has been removed?

Example being power from flow switch removed, relay maintains power to device for x minutes after.

What's the application, extractor fan?

Or you can tell me to b***** off and stop being nosey, I won't be offended ☺

 

[coopersim]

Many thanks for your help.

The application... don't laugh!

I have installed a flow switch in the feed to the shower head and a heat pad behind the bathroom mirror, ideally I want power to be supplied to this for, say, 5 minutes after turning off the shower.

 

[Taylortwocities]

Just power the heat pad from the lights.
You'll not need the mirror in the dark.

Simples!

 

[JohnW2]

Just power the heat pad from the lights. You'll not need the mirror in the dark.

True - but if the room has a window, one might well want to use the mirror when the lights are not on!

Kind Regards, John

 

[ericmark]

If the normally closed contacts feed the timer then it could power the mirror for 5 minutes after the shower has been used. But it would not be powering it while being used, and the flow switch would need normally closed contacts.

 

[JohnW2]

If the normally closed contacts feed the timer then it could power the mirror for 5 minutes after the shower has been used. But it would not be powering it while being used, and the flow switch would need normally closed contacts.

Not, I think, with the product the OP first mentioned. As I understand it, that one would result in the mirror being powered for just the first "x minutes" (5 mins or however set) from when the shower started to be used.

Kind Regards, John

 

[ericmark]

It would depend if there is both normally open and normally closed contacts in the flow switch. I can see the timer, but not the flow switch.

 

[JohnW2]

It would depend if there is both normally open and normally closed contacts in the flow switch. I can see the timer, but not the flow switch.

Ah, I see. I didn't twig that you were talking about N/C contacts on the flow sensor. I've only ever used N/O contacts with flow sensors so, to be frank, I haven't noticed whether they also have N/C ones.

In the OP's case, I imagine that he would want the mirror to heat up whilst the shower was being used (and the mirroe potentially steaming up!), rather than to just come on for 5 mins starting when the shower was switched off. As has been said, for that one needs a 'delayed off' relay/timer (and use the N/O contacts).

Kind Regards, John