•The 4-20 mA passive receivers must not contain a voltage source to power the loop current. They do require the addition of a separate isolated power supply. Typically a supply that delivers 15 to 20 volts DC at 50 mA is sufficient. Wire these as in Figure 3. Note that some 12-volt DC wall transformers (as used on portable equipment) may deliver 15 to 20 volts when they are lightly loaded. The CUI/Stack #AD-1220M is a commonly available example of a 12 volt 200mA supply that will deliver around 18 volts nominal when loaded below 20 mA.
•Be sure that both the power supply used and the passive receiver are floating (not connected to earth ground). If either is not floating, the circuit will not work and damage may occur.
•Ensure that jumper SW101 is set to the “I” position before power-up.
Page 44 of 50 | AZI Customer Service 800-528-7411 or 602-470-1414 |
