1. ## BO AND AO

What is the difference between binary outputs and analog outputs?
Binary is on and off I am thinking,
Analog outputs is the same but it is more like for a drive?
I'm doing some reading and was wondering.
Also binary and analog variables?
Last edited by milkyway; 09-09-2012 at 10:14 PM. Reason: Adding

2. binary is on/off
analog-varies, usually a signal that modifies voltage or ma based on settings

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Really? Please don't tell me you are actually billing somebody for your time.

4. Originally Posted by mechdorn
Really? Please don't tell me you are actually billing somebody for your time.
Nope, just like my post said, doing some reading,. What makes u think I am billing for my time??
Pay attention

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Check it out...
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BTW...I didn't get the job

6. A commonly used analog output signal is 4-20 milli amps or 0-10VDC with the lower end of the signal being scaled as 0% and the upper end as 100% of the signal.
A common use is a signal going to a variable frequency drive to an electric motor.

7. Binary Output (AKA: Digital) is simply on or off. Example: A control board telling a relay to turn on a fan motor.

Analog output is a variable signal used as a control signal. Example: 0-10vdc from a control board used to tell a VFD how fast or slow to drive a motor. 0vdc = 0Hz, 5vdc = 30Hz, 10vdc = 60Hz, or anything in between.

Now I want you to study up and give me examples of what a BINARY INPUT and a ANALOG INPUT could be used for.

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Originally Posted by zw17
Binary Output (AKA: Digital) is simply on or off. Example: A control board telling a relay to turn on a fan motor.

Analog output is a variable signal used as a control signal. Example: 0-10vdc from a control board used to tell a VFD how fast or slow to drive a motor. 0vdc = 0Hz, 5vdc = 30Hz, 10vdc = 60Hz, or anything in between.

Now I want you to study up and give me examples of what a BINARY INPUT and a ANALOG INPUT could be used for.

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Binary input typically used for status. typical bo's include airflow switch, safety devices, relay aux contacts. fan proof=binary input closed, ie airflow switch closed.

analog input is a control variable, could be an output off of a tempereature sensor, humidity snesor, airflow station, and other controls that give a variable response. example--an airflow station on an air handler delivering a 4-20ma output based upon differential pressure across the fan inlet cone.

10. Flange!!!!

I wanted him to answer so he could learn something ya dolt!

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Originally Posted by zw17
Flange!!!!

I wanted him to answer so he could learn something ya dolt!

Which is why I asked before starting to list stuff.

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ooppsie, thought we were doing training. my bad for sure.

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ok, well he still needs to learn some things. how do you deal with having a 2-10 volt sensor, but need a 4-20ma input??

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