MarnixW
Electrical
- Nov 3, 2020
- 1
IEC 60204-1 requires a transformer for control circuits:
9.1.1 Control circuit supply
Where control circuits are supplied from an AC source, transformers having separate windings
shall be used to separate the power supply from the control supply.
Can anyone help me with the background, the contribution to safety of such a transformer?
I know sometimes usage of a transformer has advantages. For example when there is a high short circuit current or when a machine has only 3 phase supply.
But there are also situations in my opinion it is beter whitout transformer. For example when there are long cables in control current circuits. Or when the supply system has a low short circuit current.
I know also there is an exeption, but in general it is required.
So why is it required and not just allowed?
9.1.1 Control circuit supply
Where control circuits are supplied from an AC source, transformers having separate windings
shall be used to separate the power supply from the control supply.
Can anyone help me with the background, the contribution to safety of such a transformer?
I know sometimes usage of a transformer has advantages. For example when there is a high short circuit current or when a machine has only 3 phase supply.
But there are also situations in my opinion it is beter whitout transformer. For example when there are long cables in control current circuits. Or when the supply system has a low short circuit current.
I know also there is an exeption, but in general it is required.
So why is it required and not just allowed?