Dear user,

I want to use a ON Daley timer that can time for 16 hours with hold function

so,

I used a  counter CU ( SFB0) with PLC clock memory  MB 2   bit 7 (frequency is   0.5 S)

and this helped me to reach 16 hours, also I can do hold by deactivate EN or CU parameter.

My questions are.

1. is the clock memory give accurate time with counter ?
2. is there any  ON daily timer block doing 16 hours timing with hold function?

Normally standard timers doesn't support pause or holding capability.There is an FB developed many years ago and it is available in the forum as a multi-function timer with a pulse signal.You can call it in one of the OB3X and sample rate of the cyclic interrupt is added to a register and compared to a set value.It is developed in STL and you can find it in the following link:

Timer which does not reset itself

FUNCTION_BLOCK FB 1
TITLE =
VERSION : 0.1


VAR_INPUT
trig : BOOL ;
type_sel : INT := 1;
impulse : BOOL ;
interval : TIME ;
pause : BOOL ;
set : REAL := 1.000000e+001;
reset : BOOL := TRUE;
END_VAR
VAR_OUTPUT
output : BOOL ;
elapse : REAL ;
END_VAR
VAR
store_interval : REAL ;
el_time : REAL ;
END_VAR
BEGIN
NETWORK
TITLE =

L #interval;
DTR ;
L 1.000000e+003;
/R ;
T #store_interval;
NOP 0;


A #reset;
JCN norm;
L 0;
T #elapse;
T #store_interval;
T #el_time;

NOP 0;
CLR ;
= #output;

JU fin;
/////////////////////////////
norm: NOP 0;
L #type_sel;
JL hd_r;
JU zero;
JU one; //On delay Timer
JU two;

hd_r: JU fin;
zero: JU fin;
one: NOP 0;
/////////ON Delay Timer////////////////////////////////
A #trig;
JC fst;
L 0;
T #el_time;
T #elapse;
JU fin;
fst: NOP 0;
L #el_time;
L #store_interval;
-R ;

L #set;
TAK ;
>R ;
JCN res;
A #impulse;
A #trig;
AN #pause;
JCN snd;
L #store_interval;
L #el_time;
+R ;
T #el_time;
T #elapse;
snd: NOP 0;


res: NOP 0;
A( ;
L #el_time;
L #set;
>=R ;
) ;
A #trig;
= #output;


///////////////////////////////////////
two: NOP 0;

//Under Construction!!
////////////////////////////////////////
JU fin;

fin: NOP 0;






END_FUNCTION_BLOCK

ORGANIZATION_BLOCK OB 35
TITLE = "Cyclic Interrupt"
VERSION : 0.1


VAR_TEMP
OB35_EV_CLASS : BYTE ; //Bits 0-3 = 1 (Coming event), Bits 4-7 = 1 (Event class 1)
OB35_STRT_INF : BYTE ; //16#36 (OB 35 has started)
OB35_PRIORITY : BYTE ; //Priority of OB Execution
OB35_OB_NUMBR : BYTE ; //35 (Organization block 35, OB35)
OB35_RESERVED_1 : BYTE ; //Reserved for system
OB35_RESERVED_2 : BYTE ; //Reserved for system
OB35_PHASE_OFFSET : WORD ; //Phase offset (msec)
OB35_RESERVED_3 : INT ; //Reserved for system
OB35_EXC_FREQ : INT ; //Frequency of execution (msec)
OB35_DATE_TIME : DATE_AND_TIME ; //Date and time OB35 started
END_VAR
BEGIN
NETWORK
TITLE =

// impulse

AN M 0.0;
= M 0.0;


L #OB35_EXC_FREQ;
ITD ;
T DB1.DBD 6;


CALL FB 1 , DB 1 (
impulse := M 0.0);



END_ORGANIZATION_BLOCK

TIMER.zip(65 Downloads)

As calculations are performed on real, there is a limitation in SIMATIC S7 to add a small number with a huge number.To avoid this, consider another registers to keep hours passing.When you work with huge time spans such as 16 hours , a slight calculation around 1s can be tolerated.

There is another sample for SFB4 with similar functionality, you can find it in the forum.

I hope it helps,

hdhosseini

Hello Mohanna;

First thing: the Clock memory its are based on the hardware clock of the CPUs (except the S7-312, which has a software clock). Accuracy values for the RTC on the S7-300 and S7-400 are shown as attachment below.

You will find info on the Clock memory in the following discussions:

Cyclic Interrupt or Clock Memory -

http://www.plctalk.net/qanda/showthread.php?t=35209

There is a retentive TON (TONR) available for S7-300/400 CPUs:

S7 FC80 TONR (TI-S7 Converting library in Simatic Manager); TONR_X is the TIA Portal equivalent instruction.

https://support.industry.siemens.com/tf/uy/en/posts/fc-80-tonr-timer-retentive-how-to-use/125026/?page=0&pageSize=10

STEP 7 - System and Standard Functions for TI-S7

What I have not found out is the maximum PV value you can use with these timers. I presume that the Online Help can provide this.

Hope this helps,

Daniel Chartier

Hi

TON / TOF use time as dint in ms.

The max value is a bit more than 21 days (2^31ms)