In an existing system design are (2) 24Vdc Power Supplies, located next to each other and powered by the same source. The separate DC outputs are to supply instrumentation and field devices, etc.
An example, is a Temperature Controller; primary power is from DC Supply 1, inputs used and outputs controlled by the controller are supplied by DC Supply 2. The Temperature Controller?s primary power 0Vdc and input / output 0Vdc are internally isolated.
My question is basically about multiple power supplies used on circuits describe above and other similar applications.
When should the 0Vdc (commons) of multiple power supplies be tied together if ever?
When should the 0Vdc (commons) of multiple power supplies be tied to ground? This practice of grounding the 0Vdc of power supplies has been used in most of our designs over the past few years. Although, I?ve seen on some designs where the 0Vdc (commons) are left floating.
An example, is a Temperature Controller; primary power is from DC Supply 1, inputs used and outputs controlled by the controller are supplied by DC Supply 2. The Temperature Controller?s primary power 0Vdc and input / output 0Vdc are internally isolated.
My question is basically about multiple power supplies used on circuits describe above and other similar applications.
When should the 0Vdc (commons) of multiple power supplies be tied together if ever?
When should the 0Vdc (commons) of multiple power supplies be tied to ground? This practice of grounding the 0Vdc of power supplies has been used in most of our designs over the past few years. Although, I?ve seen on some designs where the 0Vdc (commons) are left floating.
