Safety isolation barrier
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Dear teachers, I would like to ask you some questions regarding the barrier issue. I understand the wiring method for isolation barriers, but some of these barriers have their own power distribution systems. Does this type of power distribution method cause conflicts with the power supply of DCS cards? Does it not require simultaneous power distribution?
This post was last edited by ssln123 on 2016-8-16 09:36. If the power for the field instruments is supplied uniformly through an isolation barrier, then there is no need to supply power to the DCS cards; there’s no need to worry about this. Supplying power to both systems will either result in abnormal operation or damage to the equipment. It is necessary to distinguish between the operating power supply for the DCS card and the power supply for external use; in the case of central control systems, it is the jumpers on the card that determine whether external power supply is used.
If a two-wire instrument is connected to a safety barrier, it is powered by the safety barrier; the active signal is converted into a passive signal by the safety barrier before entering the card. If it is not connected to the safety barrier, the two-wire instrument is powered by a connector, and the signal is active ； Four-wire instruments require additional power supply, with passive signals.
Mm-hmm, Yokogawa is also using card jumpers