Hello respected members. I have recently discovered the vast and surprising field of Arduino, and I'm also new to electronics. I'm generally interested in home automation projects. I'm working on a few projects, one of them being water pump automation. The power motor is 1HP operating voltage of 230V. I have attached a picture of the inside of the controller. I have an Arduino Uno board and will use the GSM900 module to turn on and off the motor. My query is what relay (rating and channel) to select for the project. Will resistors or any other electronic components be required for this project? Please guide. Thank you.
Then you need a relay rated for 1 hp or more. You need a DPST relay to switch both poles of your 230 volt line.
What exactly are you wanting to do? Do you have a well, pump, pressure tank, etc?
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It is a submersible pump which I use to pump water.
How will you power the arduino?
I have no experience with arduino driven relays switching mains power. However I wonder if two of these might do the job - and they would fit inside the controller box
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If you are in North America you will need to switch both "240V" lines since they are both "hot" with respect to ground. In the rest of the world, there is only one "hot" wire and grounded neutral. Also you need "random switching" type, not "zero crossing" type used for resistance heaters. And be careful, when SSRs are "OFF" they are NOT an open circuit but a very high resistance and will leak enough current to shock the beeJesus out of you, maybe fatal with 240V.
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Hello John. U̶n̶f̶o̶r̶t̶u̶n̶a̶t̶e̶l̶y̶,̶ ̶t̶h̶i̶s̶ ̶t̶y̶p̶e̶ ̶o̶f̶ ̶r̶e̶l̶a̶y̶ ̶i̶s̶ ̶n̶o̶t̶ ̶u̶s̶e̶d̶ ̶i̶n̶ ̶A̶r̶d̶u̶i̶n̶o̶. Thank you for your comment.
Edit: A person messaged me saying it is non-sense that Solid State Relay doesn't work with Arduino. Please pardon me for my statement. I'm new to Arduino and Electronics.
I would use something like this:
2 pole contactor
And switch the coil power (about 10 watts or less) with a small relay module:
5V relay module
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Got it.
Can you please these two terms? Random switching and Zero crossing.
Thank you. Will take extra precautions.
I the 2 pole contactor necessary? I have seen a few online projects that only used a relay module. Can I select a relay module of 12V? How channel relay shall I select?
You need to use exactly the type of relay that is inside you current pump controller. You showed a picture of it. Why do you want to mess with that? Your submersible pump will likely take at least 100 amps while it begins to move the column of water against your pressure tank pressure.
Look inside the controller you have.
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I want to automate the water pump using GSM module. Below is the image of a relay which I found in many online Arduino projects. Can I use it?
Details of relay:
This is a 2-Channel Relay Module High/Low-Level Triggering Optocoupler Isolation Load 30A DC 5V / AC 250V for PLC Automation. It uses a high-power relay, the maximum control load DC 5V 30A / AC 250V 30A. In line with international safety standards, the control area and the load area with isolation slot. It comes with each optocoupler isolation, anti-interference ability.
Features:
Using high-power relay, the maximum control load DC 5V 30A / AC 250V 30A;
With each optocoupler isolation, anti-interference ability.
In line with international safety standards, the control area and the load area with isolation slot.
Each channel has a relay on the LED indication.
Product Applications: PLC automation equipment control, industrial system control, logistics network control, home intelligent product control, electronic enthusiasts to develop experiments, all kinds of circuit modification.
Specification:
Supply Voltage: DC 5V
Quiescent Current: 5mA
Maximum Operating Current: 190mA
Trigger Mode: High and low-level trigger
Load Voltage: DC 30V / AC250
Load Current: 30A
Relay Life: more than 100,000 times
I do not see any HP motor rating on your relay, do you?
Why would it have HP rating? Tell me does any relay have HP rating?
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The commercial relays I have all have motor HP ratings.
Why do you not disclose exactly what you are trying to do? And make a block diagram showing your components and how you will wire them together.
Yes. Relays have hp ratings because motors are inductive, not resistive loads.
Please once read the original post. I'm trying to control (turn on and off) my 1 HP submersible water pump using Arduino with help of GSM module.
That's why I have asked this question. Without relay how can I proceed further? I need your help.
I was not aware of that. Please pardon me.
No one can help unless you provide some information about what you want to do with your water system.
Water systems are quite complicated and can easily stop working. Please, a simple one sentence reason why you want to automate your existing system.