warning light
#1
01-10-14, 03:23 PM
warning light
long story short, the power went off to our hot tub and if froze in the -5* weather
.
what I would like to do is install a warning light that goes ON when the power goes off so this does not happen again. I thought about a light that stays on with the power on, but I don't think that wouild get the attention needed as a light coming on. Any ideas
.what I would like to do is install a warning light that goes ON when the power goes off so this does not happen again. I thought about a light that stays on with the power on, but I don't think that wouild get the attention needed as a light coming on. Any ideas
#2
01-10-14, 04:22 PM
A normally open relay with a 120v or 240v coil + 12 volt battery + 12 volt LED light.
<img src="https://myphotos.mypclinuxos.com/images/ray2047/alarm.jpg" width="650" height="450"/>
<img src="https://myphotos.mypclinuxos.com/images/ray2047/alarm.jpg" width="650" height="450"/>
Last edited by ray2047; 01-10-14 at 04:57 PM.
any idea where I might find something like this ready made?
#4
01-11-14, 04:39 AM
Group Moderator
That's a rather specialized request especially for a 240 volt circuit. I did a quick search online and could not find one ready made. Luckily it's a really simple circuit and could be made with parts ordered online.
Most important would be to get a continuous duty relay that has normally closed (NC) contacts. If a single pole single throw (SPST) NC relay is hard to find you can use a relay that has more contacts. You would just use the NC contacts and leave the others unused.
It's also possible that the controls for your spa already have a relay with NC contacts that are not being used. Some spas have a master relay as part of their safety circuit that kills power to the entire spa when you open the cabinet door.
Most important would be to get a continuous duty relay that has normally closed (NC) contacts. If a single pole single throw (SPST) NC relay is hard to find you can use a relay that has more contacts. You would just use the NC contacts and leave the others unused.
It's also possible that the controls for your spa already have a relay with NC contacts that are not being used. Some spas have a master relay as part of their safety circuit that kills power to the entire spa when you open the cabinet door.
#5
01-11-14, 07:29 AM
You need a relay that is open when energized. Here is an example: 90295Q 208/240V Coil SPDT Relay note only one set of contacts would be used. With this relay it would be either 5 or 4.
Last edited by ray2047; 01-11-14 at 07:57 AM.
