Stairway lighting switch

Short description

The edge of an input pulse triggers a configurable time. The output is reset when this time has expired. An off warning can be output prior to the expiration of this time.

Connection

Description

Input Trg

You trigger the time (off-delay) for the stairway switch with a signal at input Trg (Trigger).

Parameter

T : The output is reset (1 to 0 transition) when the off-delay time T has expired.

T ! : determines the triggering time for the prewarning.
T !L : determines the length of the prewarning time.
Retentivity on = the status is retentive in memory.

Output Q

Q is reset after the time T has expired. A warning signal can be output before this time has expired.

Parameters T, T! and T!L

The off-delay time T, the prewarning time T! and the prewarning period T!L can be provided by the actual value of another already-programmed function:

For the 0BA7 and later version devices, you can additionally use the actual values of the following already-programmed functions:

You select the required function by the block number.

Timing diagram

The prewarning time is set to 15 s. The T! and T!L parameters thus become obsolete.

Changing the time base

You can change the prewarning time base and the period.

Time base T

Prewarning time

Prewarning period

Seconds *

750 ms

50 ms

Minutes

15 s

1 s

Hours

15 min

1 min

Description of the function

Output Q is set to 1 with a 0 to 1 signal transition at input Trg. The 1 to 0 transition at input Trg triggers the current time and output Q remains set.

Output Q is reset to 0 when Ta reaches the time T. Before the off delay time (T - T!) has expired, you can output a prewarning that resets Q for the duration of the off prewarning time T!L.

Ta is retriggered (optional) at the next high/low transition at input Trg and if Ta is expiring.

Scan cycle time

For information on how to determine the scan cycle time of a LOGO!, refer to the appendix of the LOGO! Manual.

Overview