Wireless low power button trigger - Page 1
Forum section: electronics / projects

author: gonzalito
author_rank: Contributor
timestamp: May 19, 2025, 11:22:17 pm
content: Hi everyone.I have an issue I need to solve.I need to design a wireless button for activating a pump inside a machine. I need to make this wireless, and the transmitter should use as little power as necessary. This button will be pushed about 500 times a day. (its a liquid dosing machine).A single touch on the button starts a dose. pressing it again quickly stops the dosing. You should be able to dose as long as you have the button pressed for a long enough time until release.Transmitter should be powered by a 9v or so battery and it need to last a many moths as possible, and will be enclosed in a IPXX enclosure. Only the battery will be allowed to be changed.Receiver will be inside the machine.Does anyone manage how to face such an objective? any preliminary ideas?

author: Benta
author_rank: Super Contributor
timestamp: May 19, 2025, 11:27:18 pm
content: Sounds like a car key-fob to me. Cheap and built a billion times. You just need to find the make/shape/size that is appropriate.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: May 20, 2025, 01:21:47 am
content: https://www.amazon.ca/Wireless-Bluetooth-Shutter-Control-Smartphones/dp/B0113W600Metc etc etc although 500 times a day seems quite a lot, that's like every 2 minutes for a waking day.

author: Poroit
author_rank: Frequent Contributor
timestamp: May 20, 2025, 07:01:24 am
content: G'day gonzalito,As Alex suggests 500 times a day is a lot.Is it a Dosing Machine in a factory?Could you not Automate this application further?

author: tooki
author_rank: Super Contributor
timestamp: May 20, 2025, 07:31:19 am
content: Quote from: gonzalito on May 19, 2025, 11:22:17 pmWhy does it need to be wireless? Unless the taskabsolutely cannotbe accomplished with a wired button, you should use a wired one.Some things to consider:- industrial environments are often full of interference- a battery can fail at an inopportune moment- wireless could be susceptible to malicious attack- since you intend to use a toggling function (press and release to start, press and release again to stop), what happens if something goes wrong between the “start” and “stop” presses, causing the “stop” command to be delayed or lost? How much will the overfilled part cost to fix or replace? Does this create hazards to people or equipment?- who is responsible for battery changes?- what if the wireless button gets lost or stolen?Also, an industrial push button switch that can handle 500 presses a day (that’s over 100,000 presses per year!) won’t be designed to work with extremely low currents, which you’d need for long battery life. This exact issue caught out some major computer mouse manufacturers when they released new wireless models with extremely long battery life: the switch current was so far below the mouse button microswitches’ minimum wetting current that the switches failed. (They had to have custom switches made with special contacts.) Industrial buttons will be designed for even higher wetting currents than microswitches. Look into “wetting current”.

author: gonzalito
author_rank: Contributor
timestamp: May 21, 2025, 11:17:01 pm
content: Thanks everyone for the replies!!QuoteWe have tried this why a regular 433mhz keyfob (a crappy chinese one) And it sometimes didnt respond and misclicked. Sometimes you even dosed outside the place you needed to.QuoteThis is correct. Its a milk dosing machine, and the user presses a button to dose a set amount of milk. This is easily done 200+time ins the moring and also in the afternoon.So, also mechanically this button will also be stressed, but that's not a problem.The main problem is that now we are using a cable, and it gets damaged more sooner than later.Thats why we need it wireless.Now in regard to this:QuoteLoved the replies guys.PS: The receiver is inside stainless a metal case. Here is apicture of a similar machine.We tried stuff like this and failed misserably.IT might have been the crappy electronics, but before diving into something again, i neede to check on other people ideas or advices.

author: gonzalito
author_rank: Contributor
timestamp: May 21, 2025, 11:21:36 pm
content: Quote from: gonzalito on May 21, 2025, 11:17:01 pm

author: tooki
author_rank: Super Contributor
timestamp: May 22, 2025, 09:23:28 am
content: Quote from: gonzalito on May 21, 2025, 11:17:01 pmThanks for the full reply.As for the issue of cable: it seems to me the solution is simply to use a more robust cable. There’s a HUGE array of cables out there, including extremely robust ones. And there’s always the option to add further armor. (For example, the LAPP Silvyn LCC-2 series of PVC-coated steel hose are extremely flexible but would provide significant protection.)

author: gonzalito
author_rank: Contributor
timestamp: May 22, 2025, 06:12:39 pm
content: Quote from: tooki on May 22, 2025, 09:23:28 amWe are using a custom made cable, but even so we are having issues with it getting cut.The hose in our machine is singnificantly longer, and it also stretches. That is speciffically th reaeson why we are spiraling the cable around the hose. Pulling doesnt affect it as uch.The thing is that they drag the hose around and the cable grinds against the floor, eventually getting cut.We have also placed the cable inside a smaller pvc hose, so that it gets protected a bit more, but assembly of the "cable - cable cover" is not practical.A hose of 5m, need a cable+cable cover of about 7.5m in leghth.Here is our machine.

author: thm_w
author_rank: Super Contributor
timestamp: May 23, 2025, 12:08:13 am
content: What about having a boom arm with the button hanging on the end, to keep the cable off the floor.Similar to the hanging crane pendants:https://www.directindustry.com/prod/verlinde/product-8590-2048929.html

author: tooki
author_rank: Super Contributor
timestamp: May 23, 2025, 12:15:19 am
content: Quote from: gonzalito on May 22, 2025, 06:12:39 pmA PVC hose and a steel hose are hardly the same thing!!!And what kind of cable are you using now?I can’t imagine that a nice robust polyurethane (PUR) insulated cable, inside a steel hose, would be susceptible to damage. No need to coil it around the milk hose — just run them in parallel with cable ties of some sort.

author: tooki
author_rank: Super Contributor
timestamp: May 23, 2025, 12:18:30 am
content: And if you absolutely cannot be dissuaded from going wireless, don’t cobble together a solution yourself. Use an industrial remote control from an established manufacturer, for example:https://www.se.com/us/en/product-subcategory/81654-industrial-wireless-remote-control/https://www.tele-radio.com/https://www.bannerengineering.com/us/en/products/wireless-sensor-networks/wireless-pushbuttons-and-switches.html

author: gonzalito
author_rank: Contributor
timestamp: May 23, 2025, 11:38:31 am
content: Thanks for everything tooki.Im checking the steel flexbel hose and will se if we can get anything like that here in argentina; and also check the price if it need to be imported.In regards to the industrial readily available solutions I'll have to try one and see if they can hold up the amount of repetitions and the extremely harsh humid conditions of dairy farms.That has always been an issue with buttons.

author: tooki
author_rank: Super Contributor
timestamp: May 23, 2025, 04:39:36 pm
content: Quote from: gonzalito on May 23, 2025, 11:38:31 amGlad to help.I think you’re underestimating the extent to which this is completely normal stuff. There’s a zero percent chance it’s unavailable in the whole of Argentina.Quote from: gonzalito on May 23, 2025, 11:38:31 amGo look at the local distributors. Call them up and talk to representative. It’s unclear whether you’re the manufacturer of the e-milk 500 or a user of one. If you’re a manufacturer, then you shouldn’t have any trouble getting the distributors to talk to you and collaborate with you on developing a solution. Remember, yours is far from the most difficult situation that exists. There is equipment that goes down oil wells and operates inside hot oil at high pressure. There is stuff that operates inside CNC machines where it has liquid full of metal chips sprayed at it all day long. (That’s actually where I used the Silvyn LCC-2 steel hose I mentioned earlier: it was to replace the hose on a sensor inside a CNC milling machine at work.) There are cables in machines in rock quarries. Steel mills. If you can imagine a tough environment, someone has made cable and/or cable protection for it. The distributors’ application engineers have probably dealt with situations similar to yours.If you’re an end user, a distributor might not give you too much help, but they at least might be able to point you towards a local retail-level distributor that can sell small amounts.

author: jmelson
author_rank: Super Contributor
timestamp: May 23, 2025, 11:49:41 pm
content: Look on eBay for "DC 4-channel wireless RF". We used some of these in a project. They use a standard IC, so you could make your own if you need to make many of them.Jon