Totally new to Arduino world.. and just wondering if following scenario is possible.
Currently washing machine is controlled by 3 way SDPT toggle switch. On/off and Advance
What I wanted to achieve is
Control Washing Machine Mechanical timer by applying 120VAC at the certain time
And maybe possible display time left for cycle.
I have purchased
Arduino Uno
2 Channel Relay Module.
I know playing with 120VAC is not a beginners project but as long as i can properly isolate from Main it should be fairly safe i hope?
If i can make Arduino to Start timer by detecting the location of SDPT switch (on/off) 120VAC and then at certain time it can close relay to apply 120VAC to mechanical timer to quick advance to the next cycle. and once cycle is complete repeat the same cycle once toggle switch is pressed again.
If i buy Wallwart to convert 120VAC to 5DC input to Arduino it should be okay?
Any help is much appreciated and thank you in advance!
No disrespect is intended, it sounds like you may not be qualified to work with mains voltages/currents.
Suggest you study:
Inductive loads
Fusing
Wire current carrying capacity
Grounding and ground fault circuits.
Soldering
Relay contact problems
Safe electronic/electrical construction
Proper use of a DMM
Galvanic isolation
This is not all of the things that should be mastered before you proceed with this type of project.
Yes, 2 relays can be used to replace an on-off-on switch. and relays provide isolation from the power line voltage (if wired correctly).
If i buy Wallwart to convert 120VAC to 5DC input to Arduino it should be okay?
Yes, that's the easiest way to "detect" line voltage, and it's isolated.
And maybe possible display time left for cycle.
Is the cycle-time known?
If you proceed with this, take it one step at a time. Maybe try the wall-wart first and make sure you can detect the presence of 120VAC by sending a message to the serial monitor.
Then write a little program to "fake-out" the switch. Maybe try it without any critical timing or without any "input". i.e. Maybe make it wait for one minute before starting, then wait some time and "advance".
Then you can play-around with the LCD display & timer display. IMO, that's the most difficult but least dangerous part.
...You might also want to "simulate" the line-voltage stuff with low-voltage and LEDs before actually wiring-up the lethal voltage. (The 1st time I made an AC light dimmer I tested it using a 12VAC transformer and 12V light bulb.)
larryd:
No disrespect is intended, it sounds like you may not be qualified to work with mains voltages/currents.
Suggest you study:
Inductive loads
Fusing
Wire current carrying capacity
Grounding and ground fault circuits.
Soldering
Relay contact problems
Safe electronic/electrical construction
Proper use of a DMM
Galvanic isolation
This is not all of the things that should be mastered before you proceed with this type of project.
Non taken Thank you for your reply
I thought it was simple enough for me to jump on this..
it sounds like i need to study more or buy one of those relay module with time delay..
DVDdoug:
I assume that's SPDT (single pole double throw).
Yes, 2 relays can be used to replace an on-off-on switch. and relays provide isolation from the power line voltage (if wired correctly).
Yes, that's the easiest way to "detect" line voltage, and it's isolated.
Is the cycle-time known?
If you proceed with this, take it one step at a time. Maybe try the wall-wart first and make sure you can detect the presence of 120VAC by sending a message to the serial monitor.
Then write a little program to "fake-out" the switch. Maybe try it without any critical timing or without any "input". i.e. Maybe make it wait for one minute before starting, then wait some time and "advance".
Then you can play-around with the LCD display & timer display. IMO, that's the most difficult but least dangerous part.
...You might also want to "simulate" the line-voltage stuff with low-voltage and LEDs before actually wiring-up the lethal voltage. (The 1st time I made an AC light dimmer I tested it using a 12VAC transformer and 12V light bulb.)
Thank you so much for your reply i think that's what i should do..
I will definitely follow your first step. Take apart wall wart and make sure Arduino gets voltage input signal first before proceed any further.
Thank you so much again to provide the road map. Really appreciated
DVDdoug:
I assume that's SPDT (single pole double throw).
DVDdoug addition to my reply, i basically wanted to duplicate middle button SPDT to detect (120VAC to 5DC) to send signal to Arduino and start counting times and then make relay to apply 120VAC to spare (this case 4 and 5) to advance timer.
I thought piggyback from the switch and isolate 120vac to 5DC was safe enough for me to jump on.. maybe not..
Sky078:
DVDdoug addition to my reply, i basically wanted to duplicate middle button SPDT to detect (120VAC to 5DC) to send signal to Arduino and start counting times and then make relay to apply 120VAC to spare (this case 4 and 5) to advance timer.
I thought piggyback from the switch and isolate 120vac to 5DC was safe enough for me to jump on.. maybe not..
Thank you for the picture. I was going to ask if you found the schematic/wiring diagram for the device, but I see you have. Make several copies so you can mark them up as you go!
Paul
Thank you for your replies.. I was hoping i can basically replace rocker button with Arduino. Maybe like DVD doug says, i should take it one step at a time to make sure there is 120VAC coming from that switch which i can convert and send signal to the board.
