Siemens 6ED1050-1AA00-0BE8 User Manual

Page of 372
 
LOGO! functions 
 
4.4 Special functions list - SF 
LOGO! 
Manual, 04/2011, A5E03556174-01 
205
 
4.4.16 
Hours counter 
Short description 
A configured time is triggered with a signal at the monitoring input. The output is set when 
this time has expired.     
 
Symbol in LOGO! 
Wiring 
Description 
Input R 
A positive edge (0 to 1 transition) at input R resets 
output Q and sets a configured value MI at the 
counter for the duration of the time-to-go (MN). 
Input En 
En is the monitoring input. LOGO! scans the on-time 
of this input. 
Input Ral  
A positive edge at input Ral (Reset all) resets the 
hours counter (OT) and the output, and sets the time-
to-go value (MN) to the maintenance interval MI: 
• 
Output Q = 0 
• 
Measured operating time OT = 0 
• 
Time-to-go of the maintenance interval MN = MI. 
Parameter 
MI: Maintenance interval to be preset in units of hours 
and minutes 
Range of values: 
0000...9999 h, 0...59 m 
OT: The accumulated total operating time; you can 
specify an offset in hours and minutes 
Range of values: 
00000...99999 h, 0...59 m 
Q → 0:  
• 
When "R" is selected: 
Q = 1, if MN = 0; 
Q = 0, if R = 1 or Ral = 1 
• 
When "R+En" is selected: 
Q = 1, if MN = 0; 
Q = 0, if R = 1 or Ral = 1 or En = 0. 
K
4
5
(Q
5DO
3DU
 
Output Q 
The output is set when the time-to-go MN = 0 (see 
timing diagram). 
The output is reset: 
• 
When "Q→0:R+En", if  
R = 1 or Ral = 1 or En = 0 
• 
When "Q→0:R", if R = 1 or Ral = 1. 
MI = Configured time interval 
MN = Time-to-go 
OT = Total time expired since the last hi signal at input Ral 
These values are always retentive!