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How do I switch between two signals using a digital input?

Each digital input has two PIN that can be connected to any parameter, analogue or digital, within the block diagram. For example, if you wanted to switch speed demand inputs for local/remote speed control, using UIP2 for one input and UIP3 input the other with DIP2 controlling which was selected it is done as follows: -Go to CONFIGURATION, UNIVERSAL INPUTS, UIP2 SETUP and set the UIP ANALOG GOTO to 400) Block disconnect. This disconnects the default connection from UIP2 to the speed loop. Go to CHANGE PARAMETERS, SPEED REF SUMMER and set 67) SPD/CUR RF3 RATIO to zero. This is because the connection from UIP3 into the drive speed/current loop is "hard wired" internally and cannot be disconnected as you did with UIP2. Therefore you have to set its ratio to zero instead. The next task is to connect the two UIP inputs to the digital input, and then connect the digital input analogue output into the speed loop. Connecting its analogue output is straightforward. Go to CONFIGURATION, DIGITAL INPUTS, DIP2 SETUP and set its GOTO to 63) SPEED REF 2. Connecting the two values that DIP2 will switch between is slightly complicated by the fact that we need to connect two PIN together - because the PIN involved do not have GOTO or GET FROM. The solution is to use jumpers. Go to CONFIGURATION, JUMPER CONNECTIONS, JUMPER 1 and set its GET FROM to 150) UIP2 ANALOG MON and its GOTO to 312) DIP2 IP HI VALUE. Similarly, set JUMPER 2 GET FROM to 151) UIP3 ANALOG MON and its GOTO to 313) DIP2 IP LO VALUE. Incidentally, the above description makes use of a direct (non-ramped) speed input. If you wanted to apply the ramp controls which by default are applied to the input on T4 (UIP4) the technique would be to disconnect UIP4 by setting its GOTO to 400) Block disconnect and taking the DIP2 GOTO to 26) RAMP INPUT instead of 63) SPEED REF 2.


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