Shelly uni plus device queries

[auou1i]

Hello

 

I am looking at purchasing a number of Shelly uni plus devices for a project. If I supply power to the device at 12VDC, what is the minimum voltage that the digital input would need to see to register a logic high? 

 

If I provide 4.5VDC into the digital input, will this register as logic high or true? 

 

Also does the device have a dry contact output that can be triggered via wifi?

 

[Olsche]

Digital inputs triggering voltage: 1.5 V (active low level)

2 potential-free contacts solid-state relay outputs - OUT1 and OUT2

more infos you will finde here: https://kb.shelly.cloud/knowledge-base/shelly-plus-uni

 

[auou1i]

sorry for my ignorance what does active low level mean? Does that mean anything over 1.5v will register as a logic high or true ?

[thgoebel]

As other Shelly actuators, the inputs of a Shelly UNI plus are activated by a small (36μA) current flowing from IN-x (or COUNT IN) to GND. Is this current smaller than approximately 15μA, the input is disengaged. Thus, there are no high and low levels in voltage. But you may arrange pull-up or pull-down resistors according to Ohm‘s law to detect a peculiar voltage level.

Edited August 5 by thgoebel

[auou1i]

Thanks for the response. Are there other Shelly devices with a digital input and volt free outputs controllable over wifi? I have used Shelly 1s a lot, but my understanding is that you need 12v (or the same voltage as what is powering the Shelly) to enable it to detect the a switched input (on the SW terminal)

[thgoebel]

5 hours ago, auou1i said:

Does that mean anything over 1.5v will register as a logic high or true ?

As @Olsche mentioned before: Inputs are active low. Hence, voltage larger than 1,5V (with an appropriate pull-down resistor of 1 to 10kΩ) will produce a logic „zero“ - input is inactive. And vice versa…

Please be aware this is not contradictory to my explanation about input current!

[thgoebel]

4 minutes ago, auou1i said:

Are there other Shelly devices with a digital input and volt free outputs controllable over wifi?

Shelly plus 1 (SELV compliant)

Shelly Mini 1 (NOT SELV compliant)

Shelly pro 1, pro 2 and pro 3 (SELV compliant)

6 minutes ago, auou1i said:

but my understanding is that you need 12v (or the same voltage as what is powering the Shelly) to enable it to detect the a switched input (on the SW terminal)

Sorry to disagree. As mentioned above, all Shelly actuators have the same circuit behind terminal(s) SW (or IN-x):