How can the interlock that shuts off the fire isolation valve be disabled, so that the pump can start only when it is fully open?
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As the title suggests: When the fire shut-off valve at the pump inlet is not fully open, the pump should be stopped and that valve should also be closed. How is this interlock mechanism implemented, and how should it be understood? If it’s not fully opened, just let it close – otherwise it will never be able to open. What’s everyone’s logic behind this?
Two states: fully open and fully closed
Does the valve have signals indicating when it is fully open and when it is fully closed? If interlocking requires the valve to be closed, there should be a delay for judgment. For example, if it is said that the 15S valve has not been opened fully, it indicates that there is a fault with the valve itself or something of the kind, and then the valve is closed.
When it reaches the proper position, the DI signal is sent to the electrical control circuit to start the pump
I agree with the view from the 3rd floor: it is necessary to use the signals indicating whether the valve is open or closed to make a judgment; if no signal indicating an open state is received for a certain period of time, it is assumed to be a fault, and the pump is stopped along with the valve being closed.
The purpose of this interlock is to protect the equipment; operating the pump when the inlet valve has not been fully opened can lead to idling and damage to the pump. Additionally, in agreement with the opinion from the third floor, a certain delay should be implemented, as it takes some time for the valve to open completely
It’s not fully open; full open and full closed are different concepts. Why can’t it be opened all the time? Just add a delayed trigger.
I agree with the opinion from the third floor; a certain delay should be built into the interlock system, after all, it takes some time for the valve to open.