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Voltage

does the current sensor also tell the voltage to what it is connected to. we would like to monitor the current and the voltage
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Re: Voltage

The current sensor only monitors current.
If the voltage you want to monitor is a DC load you could wire it to the A+ port with a voltage divider circuit. The A+ port can't take more than 2 volts.
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Re: Voltage

No, Alan--the current sensor will not monitor
a dc circuit; it must be ac. Dave

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Re: Voltage

No, Alan--the current sensor will not monitor
a dc circuit; it must be ac. Dave


I didn't say it did monitor a DC current.
I just explained a way to monitor a DC voltage with an Mport.

I'm sure there is a way to roughly monitor DC current as well with an Mport.
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Re: Voltage

His question was about monitoring both
current and voltage simultaneously using
the current sensor.

If you assume the circuit is dc (as you did),
you can't monitor either current or voltage
with the current sensor. You can only monitor
voltage with an mPort--using a voltage divider.

You could monitor current with an mPort by
using a current shunt (which 'converts' current
to voltage); you'd need a second port.

If you assume the monitored circuit is ac (which
seems a more likely assumption), you can use
the current sensor to monitor current , but
to monitor voltage, you would need a rectifier /
filter / voltage divider circuit as input to an mPort. Dave

> HQ in Seacoast region New Hampshire U.S.A.
> Ubiquiti Certified Trainer [UCT] for:
     UBWA [AirMax] / UEWA [UniFi] / UBRSS [routers]
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Member
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Re: Voltage

I would like to monitor AC voltage and current with 2 sensors. question is how do i build something to monitor the voltage ?
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Re: Voltage

You must convert the ac voltage to dc
voltage in the range the mPort can handle.

Assume the voltage is 250Vac; use a small
transformer (even a doorbell transformer
will do) to isolate and reduce the voltage to
(for example) 24Vac. Divide that voltage by
20 using high-value resistors to yield 1.2Vac;
using a bridge rectifier and a filter capacitor
to convert to dc; the output will be about
1.7Vdc. You can use that as input to an mPort.

Be sure to use fusing and high-value resistors
to constrain current to very low values. Dave

PS: I should have added some components:
there should be a 50V MOV in the 24Vac line,
and there should be a high-speed clamp diode
of about 3V in the line to the mPort. Dave

> HQ in Seacoast region New Hampshire U.S.A.
> Ubiquiti Certified Trainer [UCT] for:
     UBWA [AirMax] / UEWA [UniFi] / UBRSS [routers]
UBNT.NH@gmail.com