Ramp control

image\block_ramp_sn.gif

Short Description

The Analog Ramp instruction allows the output to be changed from the current level to the selected level at a specified rate.

 

Connection

Description

Input En

A change in the status from 0 to 1 at input En (Enable) applies the start/stop level (Offset "B" + StSp) to the output for 100 ms and starts the ramp operation to the selected level.

A change in the status from 1 to 0 immediately sets the current level to Offset "B", which makes output AQ equal to 0.

Input Sel

SeI = 0: The step 1 (level 1) is selected.

SeI = 1: The step 2 (level 2) is selected.

 

A change in status of Sel causes the current level to start changing to the selected level at the specified rate.

Input St

A change in the status from 0 to 1 at input St (Decelerated Stop) causes the current level to decrease at a constant rate until the start/stop level (Offset "B" + StSp) is reached. The start/stop level is maintained for 100 ms and then the current level is set to Offset "B", which makes output AQ equal to 0.

Parameter

Level1 and Level2: Levels to be reached; value range for each level: -10,000 to +20,000

MaxL: Maximum value that must not be exceeded.
Value range: -10,000 to +20,000

StSp: Start/Stop offset: value that is added to Offset "B" to create the start/stop level. If the Start/Stop offset is 0, then the start/stop level is Offset "B").
Value range: 0 to +20,000

Rate: Speed with which level 1, level 2 or 0ffset is reached. Steps/seconds are issued.
Value range: 1 to 10,000

A: Gain
Value range: 0 to 10,00

B: Offset
Value range: +- 10.000

p:  Number of decimal places
Value range: 0, 1, 2, 3

Output AQ

The output AQ is scaled using the formula:

 

(Current Level - Offset "B") / Gain "A"

 

Note: When AQ is displayed in parameter mode or message mode, it is displayed as an unscaled value (engineering units: current level).

 

Value range for AQ: 0...+32767

Parameters Level1 and Level2

The level parameters Level1 and Level2 can be provided by the value of another already-programmed function:

You select the required function by the block number.

Parameter p (number of decimal places)

Parameter p only applies for displaying the values of AQ, level 1, level 2, MaxL, StSp, and Rate in a message text.

Timing diagram for AQ

image\diagramm_ramp.gif

Description of function

If the input En is set, then the function sets the value StSp + Offset "B" for 100 ms.

Then, depending on the connection of Sel, the function runs from the level StSp + Offset "B" to either level 1 or level 2 at the acceleration set in Rate.

If the input St is set, the function runs to a level of StSp + B at the acceleration set in Rate. Then the function holds the level at StSp + Offset "B" for 100 ms. After 100 ms, the level is set to Offset "B". output AQ. The scaled value (output AQ) is 0.

If the input St is set, the function can only be restarted once the inputs St and En have been reset.

If input Sel has been changed, depending on the connection of Sel, the function runs from the current target level to the new target level at the rate that is specified.

If the input En is reset, the function immediately sets the current level to Offset "B".

The current level is updated every 100 ms. Note the relationship between output AQ and the current level:

Output AQ = (current level – Offset "B" / Gain "A")

Particular characteristics to be noted when configuring

For help on analog block parameters, refer to the Analog value processing section.

Overview