7.10.4 Discrete Output Using mA Outputs and Interposing Relays
While no power output exists on the YUAA, the 24 mA output available on the mA output mode allows for driving
interposing relays external to the YUAA. Examples of such devices available on the open market are as follows:
•
Phoenix Contact PLC-RSC-24DC/21-296617, 6 Amps electromagnetic relay mounted on base terminal block
•
Crydom DR24D06 280 VAC 6A solid state relay
•
WAGO series 789 DIN mounted relay modules with various contacts, protection, and indicators available
Note 1. The user is responsible for validating the use of external devices within their application, these are only shown as
examples of what a 24 mA output can control. The output will force either 22 V at lower currents or apply a constant current
to the external relay coil, where the user should keep the current at a value matching the relay's operating current.
2. Testing is recommended to set the mA level appropriately. If set for 24 mA into a solid state driver or high resistance coil,
the actual current could differ triggering unhealthy flags.
3. User must include a flyback diode across any relay coil being driven by YUAA in mA output mode. The cathode goes to
IO+ and anode to IO-, suppressing the high voltage spike possible when the current is turned off to the relay coil.
YUAA Universal I/O Modules
Public Information
GEH-6855_Vol_II System Guide 199