Limit value monitoring

Limit 1 and Limit 2, Index 0x80n0:13, Index 0x80n0:14

If the limits of the values that can be entered in indices 0x80n0:13 and 0x80n0:14 are violated, the bits in indices 0x60n0:03 and 0x60n0:05 are set accordingly (see sample below). The indices 0x80n0:07 or 0x80n0:08 serve to activate the limit value monitoring.

Output limit n (2-bit):

• 0: not active
• 1: Value is smaller than the limit value
• 2: Value is larger than the limit value
• 3: Value is equal to the limit value

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.

• PLC:
  IEC61131-PLC contains no 2-bit data type that can be linked with this process data directly. To transfer the limit information, you should therefore define an input byte, for example, and link the limit to the VariableSizeMismatch dialog, as described in the diagram Linking 2-bit variable with additional task.



• Additional task
  2-bit variables can be created in the System Manager.

Sample for EL3062:

Channel 1; Limit1 and Limit2 enabled, Limit 1 = 2.8 V, Limit 2 = 7.4 V, representation: signed integer

Entry in Index 0x80n0:13 (Limit 1):
(2.8 V / 10 V) x 2¹⁶ / 2 - 1 = 9,174_dec

Entry in Index 0x80n0:14 (Limit 2):
(7.4 V / 10 V) x 2¹⁶ / 2 - 1 = 24,247_dec

Output: