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Wiring
• Digital Inputs – Pushbuttons - Changing the Reference
– Pulsed Increase/Decrease Reference Speed
– Term. 32 (P 306) set to “Speed UP”; Term. 33 (P 307) set to
“Speed DOWN”
– Term. 17 defaults to “Freeze Ref.” or on newer units set P 330
to “Freeze Reference” saving terminal 17 for another function.
– Sensitivity of buttons is determined by values placed in P 209
for increase speed & P 210 for decrease speed.
Here is the a diagram for using 2 Digital Inputs as a push button reference. In the example
above a NO PB is wired to terminal 32, which is programmed for “Speed UP”. A NO PB is
wired to terminal 33, which is programmed for Speed DOWN” Terminal 17 is wired directly
to +24Vdc and is set to “Freeze Reference”. In later revisions of software there is a
parameter 330 which can be programmed for freeze reference without using terminal 17.
There must be a freeze reference command in order for the speed up and speed down PB to
work.
The sensitivity of the PB to speed up and speed down are determined by parameters 209
(Ramp 2 up) for speed up and 210 (Ramp 2 Down) for speed down. The time value set in
these parameters is the hold down time it takes to go from minimum speed (0Hz) to
maximum (60Hz). If 1 second is used then holding the PB for 1 second moves the reference
from 0 to 60Hz, making is very sensitive. It is better that a value of 12 seconds be placed
here, which moves the reference from 0 to 60Hz when the PB is held down for 12 seconds,
making it less sensitive.