Changing Of The Speed Direction Of Rotation; Ramp Generator Function Block; Local / Remote Speed Reference; Holding Of The Reference - ABB DCS 500B Description

Changing of the
speed direction
of rotation
RAMP GENERATOR
function block
Local / Remote
Speed Reference
Holding of the
reference
Ramp Function in
Emergency Stop
DCS 500 Software Description
The inputs [SEL1] (1911), [SEL2] (1913), [SEL3] and (1915) con-
trol which of the reference signals ([IN1]...[IN3]) is connected to the
SUM block inside the REF SEL function block. Only one of the sig-
nals IN1, IN2 or IN3 can be connected to the SUM block at a time.
[ADD] (1916) is always connected to the SUM-block.
Input [REV] (1917) controls the output selection of the SUM-block.
If this input is set to logical state 1, the speed reference at the OUT
(10202) is negated. This can be used to change the rotation of di-
rection on a 4Q-drive.
The main function of the RAMP GENERATOR function block is to
accelerate and decelerate the motor's speed with selected time
constants to the value of [IN] (1701).
IN (1701)
20000
0 OUTPUT OF THE RAMP
SMOOTH
1 & 2
ACCEL
1&2
Figure 14 Function of the Ramp Generation function block
There are two switches in front of the ramp block. The first switch
is the LOCAL/REMOTE selector. When LOCAL control is selected
from, for example, the CDP312 control panel, the speed reference
comes from the panel link. In REMOTE control the reference
comes from the input pin [IN] (1701).
The second switch sets the reference to zero at the input of the
ramp by means of [RES IN] (1702) input pin.
If the [HOLD] (1703) input is in logical state 1, the output of the
ramp is holding the old value.
If emergency stop function is activated by drive logic EME STOP
MODE (907) = 1, then the deceleration time is read from the pa-
rameter EMESTOP RAMP (1714).
Functional Software description
SMOOTH ACTION
DECEL
1 & 2
SMOOTH
1 & 2
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