Controlling a pool pump with an Arduino - Page 1
Forum section: electronics / beginners

author: rthorntn
author_rank: Frequent Contributor
timestamp: October 01, 2013, 03:38:08 am
content: Hi,Been reading a lot on this, conflicting info, various opinions so I still have no idea.Pump is 240v Single phase 925W 1hp 3.9AI want to switch it on/off with a microcontroller.Right now I am thinking about using something like the Power-IO DDA-5V25 relays (it's the DDA-6V25 with internal MOV) fromhttp://www.power-io.com/products/dda2540.htmbut I am worried that the high cost combined with the shipping to Australia is going to blow the budget, I don't think I would get much change out of $150.http://www.power-io.com/library/photos/dinrail-contactor-schematic.htmAm I on the right track, is there a cheaper integrated snubber and MOV solution (mainly for ease of wiring and safety) that will do what I want?Thanks.Richard

author: David_AVD
author_rank: Super Contributor
timestamp: October 01, 2013, 05:05:56 am
content: Any reason you don't want to use a conventional relay to switch the motor?A DIN rail mount contactor (big relay) would be a lot cheaper than an SSR and require no heat sink.

author: Stonent
author_rank: Super Contributor
timestamp: October 01, 2013, 05:11:38 am
content: There is a product called the power switch tail and they do have a 240v version rated for 20A. They retail for $18.50 USD.http://www.powerswitchtail.com/Pages/PSTKKit.aspxYou probably need the international version which has screw terminals instead of a cord, since I think they just have US and Europe pre-wired versions.

author: rthorntn
author_rank: Frequent Contributor
timestamp: October 01, 2013, 05:31:48 am
content: Thanks!David_AVD: Isn't the issue there the coil voltage, I need to 5v at 40ma a lot of these are 12 or 24v?Stonent: I did see the power switch tail but was put off by this:http://forums.adafruit.com/viewtopic.php?f=8&t=41753in reading further in to it though the 110 volt does have double the amps and can only handle 15A though so maybe that changes it)?CheersRichard

author: David_AVD
author_rank: Super Contributor
timestamp: October 01, 2013, 06:20:02 am
content: Do you only have a 5V supply? If so, that will be a problem for a power relay.What is the Arduino powered from?

author: rthorntn
author_rank: Frequent Contributor
timestamp: October 01, 2013, 06:51:37 am
content: The Arduino is powered by 5v, Thanks to Stonent I have ordered a couple of the powerswitch 240v kits, going by the adafruit link I posted the 20A powerswitch derated to 40% because it's a motor load gives me 8A, I only need 4A so it will no doubt be fine.

author: geraldjhg
author_rank: Regular Contributor
timestamp: October 14, 2013, 08:37:01 pm
content: yeah go for the din mounted contactor and as a bonus buy an auxiliary contactand sense if it relly closedyou could use a super small ssr for the coil only as added protection to the arduino and to keepvoltages low outside the pump enclosure

author: Kryoclasm
author_rank: Regular Contributor
timestamp: October 15, 2013, 12:58:27 am
content: How about an Opto coupler connected to a 240v rated 12v relay.Use 5v to control the opto, the opto activates the 12v relay powering the 240v load.Oh, BTW... remember to keep your grounds separate. DON'T tie the 5V grounds together with 12V Grounds.

author: rthorntn
author_rank: Frequent Contributor
timestamp: October 15, 2013, 01:32:34 am
content: Thanks everyone!The 240V powerswitch tails arrived yesterday, hopefully they will do the trick.Fairchild MOC3063 optocouplerZettler AZ21501-1A-240AE 40A/240VAC power relay2 MOV'sA bunch of resistors to set the control signal voltage rangeDoes anybody have any concerns about this kit?CheersRichard

author: Kryoclasm
author_rank: Regular Contributor
timestamp: October 15, 2013, 02:20:05 am
content: Quote from: rthorntn on October 15, 2013, 01:32:34 amJust looking and the 240v version pic, looks like a nice kit, but look carefully at the output ground soldering through-hole... missing some solder? Might be worth inspecting yours.http://www.powerswitchtail.com/Documents/European%20Wiring.jpg

author: rthorntn
author_rank: Frequent Contributor
timestamp: October 15, 2013, 02:32:56 am
content: Thanks Kryoclasm!The kit is basically a bare PCB and the components, on the live and load ends you have the option of using bare mains cable in to the larger holes or the terminal blocks in the smaller holes right beside them, what you can see in the image you have attached is the load side using a terminal block is not in the larger hole which then looks like it's missing solder.

author: scott216
author_rank: Regular Contributor
timestamp: October 20, 2013, 11:36:00 pm
content: I have an Arduino controlling my pool pump and I use this solid state relay:Carlo Gavazzi RJ1A60D50Uhttp://www.gavazzionline.com/pdf/rjdatasheetmidi.pdfIt works great.

author: rthorntn
author_rank: Frequent Contributor
timestamp: October 20, 2013, 11:39:09 pm
content: Thanks scott216, how big is your pump >2hp?

author: scott216
author_rank: Regular Contributor
timestamp: October 21, 2013, 02:33:51 am
content: My pump is 1.5 hp. It pulls about 9 amps at 230 volts. This SS relay is actually quite a bit over-sized. But I know the pump can pull a lot more when there's a problem and I wanted the relay to handle it.

author: chibiace
author_rank: Regular Contributor
timestamp: October 21, 2013, 05:36:57 am
content: im quite fond of omron relays like the g2r series

author: peter.mitchell
author_rank: Super Contributor
timestamp: October 21, 2013, 08:37:32 am
content: I don't see why you can't just use one of thesehttp://www.digikey.com.au/product-detail/en/T90S1D12-5/PB109-ND/44912