Limit 1 and limit 2, Swap Limit Bits

Limit 1 and limit 2, index 0x80n0:13, index 0x80n0:14

If the value exceeds or falls below these values, which can be entered in the indices 0x80n0:13 and 0x80n0:14, then the bits in the indices 0x60n0:03 and 0x60n0:05 are set accordingly (see example below). The indices 0x80n0:07 or 0x80n0:08 serve to activate the limit value monitoring.

Output limit n (2-bit):

Limit 1 and limit 2, Swap Limit Bits 1:

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.

Limit 1 and limit 2, Swap Limit Bits 2:

Linking in the PLC with 2-bit values

The limit information consists of 2 bits. Limitn can be linked to the PLC or a task in the System Manager.

Limit 1 and limit 2, Swap Limit Bits 4:
Linking of 2-bit variable to additional task

Example for EL3162:

Channel 1; Limit 1 and Limit 2 enabled, Limit 1 = 2.8 V, Limit 2 = 7.4 V, representation: signed integer

Entry in index (Limit 1): 0x8000:13
(2.8 V / 10 V) x 216 / 2 - 1 = 9.174dec

Entry in index (Limit 2): 0x8000:14
(7.4 V / 10 V) x 216 / 2 - 1 = 24.247dec

Output:

Input channel 1

Index 0x6000:03

Index 0x6000:05

1.8 V

0x01hex, (Limit 1, limit value undershot)

0x01hex, (Limit 2, limit value undershot)

2.8 V

0x03hex, (Limit 1, limit value reached)

0x01hex, (Limit 2, limit value undershot)

4.2 V

0x02hex, (Limit 1, limit value exceeded)

0x01hex, (Limit 2, limit value undershot)

8.5 V

0x02hex, (Limit 1, limit value exceeded)

0x02hex, (Limit 2, limit value exceeded)

Swap Limit index 0x80n0:0E

The limit function can be inverted by SwapLimitBits in index 0x80n0:0E.

Output Limit n (2-bit):

SwapLimitBits setting

Value

FALSE (default setting)

  • 0: not active
  • 1: value < limit value
  • 2: value > limit value
  • 3: Value is equal to the limit value

TRUE

  • 0: not active
  • 1: value > limit value
  • 2: value < limit value
  • 3: Value is equal to the limit value

The Swap limit function is available according to the table below

Terminal

Swap limit function from

EL31x1, EL31x4

All firmware versions

EL3112-0011

All firmware versions

EL3102

Firmware 08

EL3112

Firmware 08

EL3122

Firmware 08

EL3142

Firmware 08

EL3152

Firmware 09

EL3162

Firmware 08

EL3174, EL3174-00xx

All firmware versions