Rockwell Automation 1336E IMPACT Adjustable Frequency AC Drive User Manual V 1-4.XX User Manual

Page 185

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Using the Function Block

10-15

Figure 10.18
Up/Down Counter Function Block

When a rising edge occurs, on In1, the output is incremented by the
value in In4, and on In2, the output is decremented by the value in
In5. The output can be either a word or a double word.

To clear the counter, set In3, which loads the counter with the In7
value. As long as In3 is set, the counter remains at the In7 value, even
if In1 or In2 is toggling.

As an example of the up/down counter function block, you could
create a shuttle. When you press the start button, a start forward
command is sent to the drive, the shuttle begins to move from A to H,
and the drive follows the first preset speed. As the shuttle passes each
switch, the value of In1 is incremented and a new speed reference is
used. The speed references are set using Speed Ref 1 (parameter 29)
through Speed Ref 7 (parameter 36).

When the shuttle reaches relay H, then a stop command is issued and
the value of In1 is decremented. When you press the start button
again, a start reverse command is sent to the drive and the shuttle
moves from H to A following the preset speeds as they are
incremented by each switch.

Figure 10.19 shows an example of a shuttle.

200

Func 1 Eval Sel

0 – 17

198

Function In1

199

Func 1 Mask/Val

I

V

Up/Down Counter

Function Block

203

Func 2 Eval Sel

0 – 17

201

Function In2

202

Func 2 Mask/Val

I

V

212

Function Sel

11

In1 – Count up (rising edge)
In2 – Count down (rising edge)
In3 – Load counter with 0
In4 – Up increment
In5 – Down increment
In6 –

If:

Then Output is:

False

A word

True

A double word

In7

Clr Value

In1

In2

213

Function Output 1

206

Func 3 Eval Sel

0 – 17

204

Function In3

205

Func 3 Mask/Val

I

V

In3

208

Function In5

209

Function In6

In5

In6

207

Function In4

In4

214

Function Output 2

(For the double word

for Input 6)

210

Function In7

In7

If In6 is:

Then the output is:

False

A word value passed to Function Output 1.

True

A double word value with the high word passed to Function Output 1
and the low word passed to Function Output 2.

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