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WEMO Maker Inventor
Posts: 8
Registered: ‎05-22-2014

Re: Available Sensors

This update should be on the home page of the community so everyone can see.  Lots of people are buying analog sensors based off the WeMo Maker Kit specs page.  Please update this and put up a NOTICE to everyone.

WEMO Maker Inventor
Posts: 1,361
Registered: ‎06-14-2014

Re: Available Sensors

What is the update that's required?  The specs look fine to me, I'm probably missing something...

 

I see a post here suggesting that you must use a low triggering sensor, but that doesn't sound right.  I know for certain the Maker sends an event for either change a low OR high signal.  I see a rule for it in the belkin app (though I use my own app for this).  I haven't tried it, but a 3.3V high signal should send a "Sensor not triggered" event which you could take action on according to the specs which call for 2.4V to trigger (and this sounds quite reasonable to me as a TTL input).

 

Looking at the PIR specs nothing jumps out at me as a problem (though you really do need to try to be sure).  That parallax one looks ideal at 5V with < 130uA load.  Basically you need to pull about 1mA through the PIR sensor output from the Maker's input (5V/4.7K=1mA), best I can tell the PIR can handle about 23mA.  The Maker can supply 100mA at 5V, much more than enough.  If there's any doubt you can use the inverter below, it has very high impedence (low current) inputs and more than enough output to drive the Maker.

 

You wouldn't need a Arduino if all you want to do was invert the signal.  Use a TTL 74LS04 or 74LS06 inverter if everything is 5V or less.  You can power it straight from the maker sensor itself.

 

@Chadster, it depends on the output, if you point me to the specs one I could probably tell you.  Basically you want it to be an open collector output (meaning it either pulls to ground when triggered, floats at the Maker's 5V when not).  If it's not buffered then you could use a transistor or a CMOS inverter that's tolerant of the 24V in and has an open collector output.  Though I'd try to find a 5V sensor, why bother with a secondary power supply?

 

 

WEMO Maker Inventor
Posts: 221
Registered: ‎05-23-2014

Re: Available Sensors


MikeP wrote:
 

@Chadster, it depends on the output, if you point me to the specs one I could probably tell you.  Basically you want it to be an open collector output (meaning it either pulls to ground when triggered, floats at the Maker's 5V when not).  If it's not buffered then you could use a transistor or a CMOS inverter that's tolerant of the 24V in and has an open collector output.  Though I'd try to find a 5V sensor, why bother with a secondary power supply?

 

 


The reason for the 24v power supply is that control applications and hardware for the most part are designed for that voltage. From my experience finding 24v contactors for 110\240\380V switching, 24V proximity and 24V optic sensors is easy. Trying to source a 5V is very hard and 3.3V is down to transistor relays.

You mention the WeMo maker sensor is sinking then I would assume a 24V sensor could work.

 

What I have done in the past (that would work) and isn't too expensive is use a 24V ice cube relay triggered by the 24V sensor to trigger a lower voltage input.

Smiley Wink Please remember to Kudo those that help you.

Belkin
Communities Technical Support
WEMO Maker Inventor
Posts: 1,361
Registered: ‎06-14-2014

Re: Available Sensors

Yep, a 24v relay pulling the signal to ground would work.  Of course you shouldn't let anything put a 24V signal to the maker.  Another good choice would be the 4N25 family of optocouplers.

 

To switch line current from TTL you might use something like http://www.ebay.com/itm/5V-One-1-Channel-Relay-Module-Board-Shield-For-PIC-AVR-DSP-ARM-MCU-Arduino/3...

WEMO Maker Inventor
Posts: 45
Registered: ‎07-31-2014

Re: Available Sensors

UAVflyhigh...

 

I'm creating a consolidated post to make it easier to understand and for new user to avoid purchasing the sensors mentioned eariler in this post.

Eric

_________________________________________
http://community.wemo.is/t5/Discuss-WeMo-Maker/How-to-guide-for-testing-the-WeMo-Maker-without-sensors-attached/m-p/1852#U1852
http://community.wemo.is/t5/Discuss-WeMo-Maker/Sensor-Fix-Options-for-converting-an-active-high-circuit-to-an/m-p/2522#U2522

Connect on LinkedIn: https://www.linkedin.com/in/ericmadej
Posts: 20
Registered: ‎01-08-2015

Re: Available Sensors


tterag2wemo wrote:
Could Belkin maybe provide a list of known working sensors? The Inventors who have successfully used sensors too?

Great idea! Anyone at Belkin reading this? Smiley Happy

Posts: 7
Registered: ‎12-25-2015

Re: Available Sensors

Hi to all!

I'll try to explain you my problem. Excuse for my poor english!

I drive a pellet Heater with closure a clean contact by intercepting a membrane button.

When i press button i with a closure contact of 5 seconds in toogle mode i start my pellet heater.

Next problem how to recognize status of heater if is functioning or not because if heater is already

in working i must stop it wit another closure contact ofr 5 seconds of the same button.

I take closure signale form two wires saldering on board.

How can i use sensor input for example test a particular led present on board is ON or OFF by sensor input lead?

What is correct connection if it's possible.

I think yes workimh in TTL mode input but i don't know very well it.

To avoid problem to Wemo MAker or heater board!!
 :-)

 

I hope you could give me some info for this

Thanks in advance for info and best regards

 

Markee

Posts: 1
Registered: ‎01-10-2016

Re: Available Sensors

Do you have it available somewhere? I am looking for compatible motion sensors in particular. 

Posts: 5
Registered: ‎03-19-2016

Re: Available Sensors

Posts: 20
Registered: ‎03-27-2017

Re: Available Sensors