Will the motor continue to run after switching from manual to automatic mode?
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This post was last edited by raifacn on 2017-6-8 23:36. In chemical processing environments, the on-site control panel is switched to \"manual\" mode to start the motor manually, and then switched to \"automatic\" mode. Will the motor continue to run at this point? If it continues to operate, is it done through electrical means or via a DCS program? If it continues to run, it is now possible to return to the control room to remotely monitor the motor without any interruption (no need to restart it on the DCS).
This is not possible; the local and remote circuits are connected to the control circuit separately, and each time a switch is made, the corresponding control circuit is disconnected, causing the motor to stop rotating.
Of course this is possible; generally, the motor control blocks in DCS systems have an on-site tracking function that enables disturbance-free switching
Automatically, it should be the DCS that controls starting or stopping; switching to automatic mode will not stop the motor, as the motor is self-locked.
Controlling the start and stop of a motor usually involves pulse signals, with self-locking on the electrical side; therefore, in theory, switching between remote and local control after starting the motor on-site will not affect its status
Let’s see how DCS and the electrical team work together Under normal conditions, automatic operation is started and stopped by the DCS; in manual mode, after startup at the field side, the start signal on the DCS side should remain untriggered, which is why operation stops once switching to automatic mode. Additionally, the manual/automatic switch at the field side disconnects the secondary circuit for a short period during the switching process
It’s possible; larger units are usually started manually on-site before switching to automatic mode. Remote starting is generally not allowed, especially for large units. I’m not sure if that’s correct.: