How to use the DC block in the deltab system?
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I’m asking for help – what does the DC block in DELTAV mean, and how exactly is it used? The description in the BOL is completely unreadable. It’s so simple that I don’t even know what this block is used for. . In the examples provided in the documentation for 6009, the explanation regarding the two-state interlock of the motor is too simplistic. My understanding is that IO-IN represents the feedback signal indicating the motor’s operating status (*-2), while IO-OUT represents the value that triggers the motor to start. When the interlock is not active, the passive \"1\" value of IO-IN corresponds to the active \"1\" value of IO-OUT, and a 0 corresponds to a 0. The DC block then determines whether to output a \"1\" signal to IO-OUT by calculating the value of SP-D. The question is: how is the value of SP-D calculated? In the example, the mode is set to auto. According to the instructions in the BOL, the set value remains at the value from the last run of the function block or the value entered by the operator last time; assuming this value is 0, then SP-D is 0, and consequently IO-OUT is also 0. So how can the motor be started? I really can’t understand it. Could some expert please explain it in detail?:
This post was last edited by budaoweng123 on 2017-11-30 15:36. SP_D stands for SETPOINT FOR DEVICE. That is, in AUT mode, the operator sets the SP value through the panel. 0 Stop, 1 Start
Mm. I understand SP-D; in the example of 6009 mentioned above, the DC block reads the SP value and then, through STATE-MASK, determines the OUT value. That’s how it should work, right? I searched for relevant information online, and there is an example where entering 1 means the valve is fully open, entering 2 means the valve is fully closed, with the output representing the command to open or close the valve. STATE-MASK is 0, 1, 0; 1, 0, 1. The meaning is: 0 indicates the valve is in the open position, while 1 indicates it is in the closed position; an output of 0 means the valve is closed, and an output of 1 means the valve is open. It’s even harder to understand. If the operator gives the command to open the SP valve, in case 1 my valve is already closed, and the OUT output indicates that the valve is closed – I don’t understand this! ! In Case 2, is the SP valve-opening command issued only after it is detected that the valve has opened to the proper position? ? ?
You’d better take a screenshot and show it. I feel like you’ve mixed up the matrix graphs in the state mask
How do I add a screenshot? . That’s called Matrix Co. I really don’t understand at all.
How do I add a screenshot? . That’s called Matrix Co. I really don’t understand at all.
Is this how to upload a screenshot? This is the example mentioned above: two signals are input, namely the valve being fully open and the valve being fully closed, and the output is the valve operation command. The matrix diagram is as shown in the picture. 1. When the operator issues an SP start command, how should one interpret the matrix diagram at this time? 2. If the operation issues a command to turn off the SP, how should the matrix diagram be interpreted?
This post was last edited by budaoweng123 on 2017-12-1 at 13:58. The description under Image 11 has an issue and can lead to misunderstandings. In your example, it is recommended to understand PASSIVE as CLOSE and ACTIVE1 as OPEN. That is, in AUTO mode, without interlocks and in pure manual operation. If the operator sets SP to OPEN via the facaplate panel, then after going through the internal logic of the DC block, IO_OUT_1 will be set to OPEN, i.e., 1. In this way, channel CH05 on card C09 supplies power to the on-site solenoid valve through a relay. Then the open feedback of the valve closes to 1, entering channel CH02 of card C13; that is, IO_IN_1 becomes 1, which corresponds to the OPEN state in the matrix diagram. The OPEN command ultimately received a response of OPEN, thus concluding a complete and successful operation.
Does it mean to first check the status bit OUT-1 on the right side of the matrix diagram, which can be 1 or 0, and then look for the feedback in IN-1 and IN-2 on the left side? Check if it’s normal?
A normal DO block, after receiving the SP value, outputs OUT-D, which can be used directly to control the valve on site. Then this DC block introduces the STATEMASKS state mask, which makes things much more complicated.