Power And Grounding - Delta Controls DZNR-768 Installation Manual

Power and grounding

Power and grounding
The DZNR-768 uses a 24VAC Class 2 power supply. One transformer may be used to
independently supply power to the DZNR.
Alternatively, you can share one transformer to power the DZNR, additional controllers and/or
auxiliary field devices such as sensors and actuators. When this approach is taken, the
following conditions must be met:
All devices MUST be half-wave rectified. Mixing power between half-wave and full wave
•
rectified devices will damage both the transformer and connected equipment.
The transformer is properly sized, including line losses for the total VA requirements.
•
Polarity is observed between controllers with respect to 24~ and GND.
•
Each controller is grounded as shown in the diagram below. This is important to protect
•
equipment and ensure a common ground reference for RS-485 communications.
The transformer secondary is fused for its maximum rated load (4A max for Class 2
•
circuits).
All devices sharing power must be on the same network segment.
•
X1 X2
24VAC
Ground the ground lug
Page 12 of 28
If no ground lug is present, ground
any one terminal labeled GND
DZNR-768 Revision 1.2 Installation Guide
Document Edition 1.5