I'm building a circuit to protect the house in case the washing machine outlet hose splits or comes lose, flooding the utility room floor. The schematic I'm following only creates a warning siren when triggered, but a lot of damage can occur in the few moments between being alerted and shutting off the power, even if I hear it sound, so I'd like it to shut off the power directly/automatically instead (and then make a warning noise as a secondary consideration, perhaps). So, how best to interrupt the mains? I'm of the mechanical relay generation but I'm guessing there's a better solid state solution around nowadays. Mains in my neck of the woods is 240VAC single phase, by the way and of course this will be an inductive load.
I think that's what we call an RCD over here. In which case, since there's only one at the main meter, it would turn off the fridge/freezer and god knows what else as well.
Why would an outlet hose split and so what if it does. It's under no pressure. Just make sure it can't disengage from the drain. Also, protect the supply lines with anti-flood devices (or hoses).
Power isn't that much of an issue. The damage can run into the tens of thousands anyway. If the power supply is where it can get wet it probably should be GFCI protected anyway.
No, Use a relay to interrupt the feed. ...Jim Thompson
-- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at
formatting link
| 1962 | Oh Lord I pray... Grant me the senility to forget the people I never liked anyway, The good fortune to run into the ones I do like, And the eyesight to tell the difference.
When I managed my father's apartment building, I had to build such a device to prevent the washing machinery from flooding the basement, which did not have a proper drain. When the power turns off, so do the various water valves, which is rather convenient. For killing the power, I used a latching relay. Nothing special, just a relay with an extra contact that energized the solenoid and held it closed as long as power was applied. Break this connection and the relay remains open until manually reset. I used overkill contact ratings so that I didn't have to worry much about opening and arcing the contacts under load. Still, you should worry about arc suppression. I probably should have added a time delay to handle power glitches and brownouts, but didn't bother. You might be able to use an SSR (solid state relay) but without the washing machine current specification, I don't want to recommend anything.
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
If you have a GFI breaker, it will take very little current to ground to trip it. Small relay and a resistor or light bulb maybe, high side to earth ground.
Actually, replacing your existing breaker with a GFI breaker should do what you want with no assistance. Any water-induced conduction to ground will trip the breaker.
I've had a similar idea for replacing a grey water sump tank. If the sump tank over flows, Shut the washer main power via a relay ( latching is a plus as Jeff points out) FYI, we never had a split hose, but the sump pump cloggs once in a blue moon.
Or maybe a solid state relay: The trick is to power the water detecting circuitry from the washing machine side of this switch (through a transformer). If the power goes away or the flood water detector goes away, the voltage driving the SSR also goes away, leaving the SSR in an OFF condition. Not exactly a latch but good enough for the intended purpose.
This looks interesting:
I've managed to make it through life this far without ever owning a washing machine or dryer. I'll let the laundromat owner deal with the broken hoses and flooding. However, I have managed my fathers apartment buildings and my rentals, which were cursed with plumbing problems and destructive tenant problems. Most often, the ends of the hot and cold water supply hoses were mangled by tenants moving the washer around for cleaning, retrieving lost items, and for no obvious reason. It takes a few years for the rubber to ossify into a brittle and inflexible rock, after which any bending will crack the hose. I made it a point to replace these hoses roughly every 5 years. Occasionally, the water pressure would dramatically decrease and then radically increase when the water department was "cleaning" the lines. One such event blew out all the rubber hoses and water heaters in the building. Of course, the water department denied all knowledge and claimed that there were no other such claims.
I'm told that the new stainless steel hoses are improved because they last twice as long and cost twice as much: My guess(tm) is that it's not the cool looking stainless mesh that improves longevity. It's the reinforcing stainless sleeve at both ends that prevents making sharp bends. This improves longevity by controlling the bend radius and preventing the hose fitting from cutting into the heat hardened rubber hose.
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
There's not remotely enough pressure in the outflow of a washing machine to create an "aneurysm" (if that's even the right word in this context). There is enough pressure, however, to dump several gallons of water over the floor before you'd have time to hit the 'off' switch.
Right, so they make little sense for a drain line.
A couple of gallons on the floor shouldn't do a lot of damage. I certainly don't worry much about washer drain lines, though I did have one work out of the pipe. I just tied it down so it wouldn't happen again.
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.