ELECTRIC CURRENT COUNTDOWN INTERRUPTER.

[EASTERN INDIGO]

Many years ago I had a simple device. It had a spring-loaded dial on the front, and you could turn the dial to any unit up to 60 minutes. It plugged into the wall. Then I could plug my device into it and set it to (for example) 20 minutes. It immediately cut the electric and started counting down. When the dial hit zero the appliance would turn back on. THIS IS NOT A CONVENTIONAL TIMER. It does not care what time of day it is, and there is no option to set a schedule. Totally non- digital. Its only function is to temporarily cut off power and then automatically turn it back on. Every timing device I have investigated for the past year or so works on a preset schedule, i.e. you cannot just walk up to it whenever you feel like it and just set it and forget it. You must always set a time or unset a time, or whatever fiddling is necessary. There are timers that will turn on electric and then turn it off. I need the exact opposite. I crashed a very loved group of animals by forgetting to plug it back in. I realize there are pumps that do the same thing, but some of my aquariums have non-adjustable pumps. Anybody know where to get OR HOW TO BUILD such a device? Thanks.

 

[KStatefan]

You need a timer that has NC contacts. Read the SPDT part of the following instructions for an Intermatic FF32HH
They have them with different times and without hold I just selected one randomally that was SPDT.

https://www.intermatic.com/-/media/inriver/12649-113302.ashx/FF%20Instructions

FF32HH - Intermatic

www.intermatic.com

 

[KStatefan]

Many years ago I had a simple device. It had a spring-loaded dial on the front, and you could turn the dial to any unit up to 60 minutes. It plugged into the wall. Then I could plug my device into it and set it to (for example) 20 minutes. It immediately cut the electric and started counting down. When the dial hit zero the appliance would turn back on. THIS IS NOT A CONVENTIONAL TIMER. It does not care what time of day it is, and there is no option to set a schedule. Totally non- digital. Its only function is to temporarily cut off power and then automatically turn it back on. Every timing device I have investigated for the past year or so works on a preset schedule, i.e. you cannot just walk up to it whenever you feel like it and just set it and forget it. You must always set a time or unset a time, or whatever fiddling is necessary. There are timers that will turn on electric and then turn it off. I need the exact opposite. I crashed a very loved group of animals by forgetting to plug it back in. I realize there are pumps that do the same thing, but some of my aquariums have non-adjustable pumps. Anybody know where to get OR HOW TO BUILD such a device? Thanks.

Is that not what you were looking for?

 

[WVNed]

Not sure he understands basic wiring but would work.

SPDT For applications requiring 3-way switching (2 timers or timer and 3-way switch) or reverse action applications. Reverse action applications allow a load to be turned “OFF” for a limited time, after which the load will switch back “ON”.