Beckhoff EPI4 Series, Documentation

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Commissioning and configuration
EPI4xxx, ERI4xxx 62 Version: 1.6
5.7.4 Limit 1 (Index 0x08n0:13) and Limit 2 (Index 0x08n0:14),
Swap Limit bits
Limit 1 (index 0x08n0:13) and Limit 2 (index 0x08n0:14)
Indices 0x08n0:07 and 0x08n0:08 are used to activate limit value monitoring.
If the limits of the values that can be entered in indices 0x08n0:13 and 0x80n0:14 are violated, the bits in the
indices are set accordingly (see the table and the example below).
Channel Index for Limit 1 Index for Limit 2
1 0x60p0:03 0x60p0:04
2 0x60p0:0C 0x60p0:0D
3 0x60p0:15 0x60p0:16
4 0x60p0:1E 0x60p0:1F
With p = 0 for Port1.... p = 3 for Port4
Limit output (2 bit):
0: Limit function not active
1: Value < limit value
2: Value > limit value
3: Value = limit value
Limit evaluation
The limit evaluation assumes a signed representation. The conversion to the desired representation
(index 0x80n0:02) only takes place after the limit evaluation.
Example limit evaluation for EPI3174
Port1, channel 1; Limit 1 and Limit 2 enabled, Limit 1 = 2.8 V, Limit 2 = 7.4 V, representation: signed integer
Input in index 0x0800:13 (limit 1):
(2.8 V / 10 V) * 2
16
/ 2-1 = 9,174dec
Input in index 0x0800:14 (limit 2):
(7.4 V / 10 V) * 2
16
/ 2-1 = 24,247dec
Output:
Input channel 1 Limit1 index 0x6000:03 Limit2 index 0x6000:04
1.8 V 0x01
hex
, (Limit 1, limit value undershot) 0x01
hex
, (Limit 2, limit value undershot)
2.8 V 0x03
hex
, (Limit 1, limit value reached) 0x01
hex
, (Limit 2, limit value undershot)
4.2 V 0x02
hex
, (Limit 1, limit value exceeded) 0x01
hex
, (Limit 2, limit value undershot)
8.5 V 0x02
hex
, (Limit 1, limit value exceeded) 0x02
hex
, (Limit 2, limit value exceeded)
Swap Limit Index 0x80n0:0E
The limit function can be inverted by SwapLimitBits in index 0x80n0:0E.
Output n (2 bits):