E-4 Velocity StepLogic™, Basic Logic and Timer/Counter Functions
Timer Function
Digital inputs and outputs control the timer function and are configured
with parameters A051
-A054 [Digital Inx Sel] set to 18 “Timer Start” and
20 “Reset Timer”.
Digital outputs (relay and opto type) define a preset level and indicate
when the level is reached. Level parameters A056
[Relay Out Level],
A059 [Opto Out1 Level] and A062 [Opto Out2 Level] are used to set the
desired time in seconds.
Parameters A055
[Relay Out Sel], A058 [Opto Out1 Sel] and A061
[Opto Out2 Sel] are set to option 16 “Timer Out” and causes the output
to change state when the preset level is reached.
Example
• Drive starts up and accelerates to 30 Hz.
• After 30Hz has been maintained for 20 seconds, a 4-20mA analog
input becomes the reference signal for speed control.
• The timer function is used to select a preset speed with a 20 second
run time that overrides the speed reference while the digital input is
active.
• Parameters are set to the following options:
– P038
[Speed Reference] = 3 “4-20mA Input”
– A051
[Digital In1 Sel] = 4 “Preset Freq”
– A052
[Digital In2 Sel] = 18 “Timer Start”
– A055
[Relay Out Sel] = 16 “Timer Out”
– A056
[Relay Out Level] = 20.0 Secs
– A071
[Preset Freq 1] = 30.0 Hz
• The control terminal block is wired such that a start command will
also trigger the timer start.
• The relay output is wired to I/O Terminal 05 (Digital Input 1) so that
it forces the input on when the timer starts.
• After the timer is complete, the output is turned off releasing the
preset speed command. The drive defaults to following the analog
input reference as programmed.
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