0-10 VDC Overview

 What is a 0-10 Vdc signal and what is it used for?

0-10vdc is an analog control signal used to control damper and valve actuators, VFD Control, temperature, humidity, pressure sensors, and temperature reset. It is a very common control signal used in the HVAC industry that is straightforward, easy to troubleshoot, and widely accepted throughout the world.

| How is it measured?

Using a voltmeter capable of checking DC voltage. 

Step 1.  Identify the wires signal (+) and the negative/common (-)

Step 2.  Set your meter to DC Volts

Step 3. Place the positive lead from the meter to the signal output terminal (Example: White wire in the picture below) and the negative lead on the ground/common terminal (Example: Black wire in the picture below).

Step 4: Notice the output voltage is 5vdc which is the midpoint of a 0-10vdc signal. (For example, if this was a  damper actuator the damper would be open halfway or 50%).

| How does this relate to SmartNodes?

The SmartNode has two 0-10vdc analog inputs and two 0-10vdc corresponding outputs. The output voltage can be varied to test devices connected to the outputs. (Example Damper or Valve Actuator) 

 | How to perform output test? 

1. Selected outputs can be tested using the following steps. Press the right arrow button on the 75F logo and scroll to the outputs menu screen.

2. From the outputs menu on the SmartNode press the down button to select the desired analog output.

3. Press the right button and note the default value of the output. Press the up and down buttons to change the range, voltage, or action of the output. (Example 0v -> 7v)

4. After testing the return value of the output to its default setting, press the left button and then the up button to return to the menu.

| Points to Remember

When checking a 0-10vdc signal the meter leads must be connected in parallel with the signal wires not in series like a 4-20ma signal.

The positive lead connects to the source of the 0-10vdc signal.

The negative lead connects to the ground/common.