User manual

Publication 1760-UM001A-EN-P
7-8 Retention
The circuit above functions in the same way as an impulse relay switch. The make
contact remains switched on in the first Pico cycle if
• a coil is actuated by the make contact of a retentive marker (series and parallel
connection both apply here too) and
• when the power is switched on, the reset condition for this retentive marker is
on.
The enable time T2 prevents Q1 from flickering.
Retentive Timing Relays
Use of Retention
The retentive timing relays T7, T8 can be operated retentively in all six different
switching functions. The retention setting only works under certain conditions for
the switching functions. These can be subdivided into groups 1 and 2.
If these conditions are not fulfilled, the actual value is cleared when the power is
restored. If the R coil (Reset) is actuated, the actual value is also cleared.
Retention with Group 1
Requirement:
When power is applied to Pico, actuated trigger coils TT7, TT8 can retain their
state '1'
'1''1'
'1' (switched on) until the preset time period has elapsed. This can be
implemented using retentive markers or inputs connected to power.
Retention with Group 2
Requirement:
When power is applied to Pico, actuated trigger coils TT7, TT8 can retain their
state '0'
'0''0'
'0' (switched off) until the preset time period has elapsed. This can be
implemented using retentive markers or inputs connected to power.
Group Retentive Function
Group 1 On-delayed
On-delayed switching with random range
Single-pulse
Flashing
Group 2 Off-delayed
Off-delayed switching with random time range