Timers

I worked with timers. I used 2 timers in one function block to activate/deactivae with delay outputs. The problem is that if this function block was used in OB1 everything was ok, but as soon as I call this FB from OB35 program works different then before. What can cause this?

i think the problem is in ob35
this block is called every 100ms

not exactly every 100ms. I set it to 20ms, timer counts 1s.

Amr Hassan said:

i think the problem is in ob35
this block is called every 100ms

Click to expand...

Or any other time you have set in the hardware configuration of the plc.

How many times are you calling the FB ? Once from OB1 and once from OB35, or just once from OB35 ?

just OB35. There works also easy motion control. and for now on FB100 for ET200S FC. Both work ok. Only with timers is something wrong.

What kind of timer are you using. S5 timer or IEC timer ?

I think that an IEC timer should work correctly even if it is not called in each scan.
An IEC timer stores the CPU time when it was started, and then compares the stored value with the current CPU time to calculate the expired time. Thus it will work even if there are "gaps" in the calls to the IEC timer.

S5timers are similar, once started, they will time even if the block that started them is no longer called.

You are right Simon.
Actually it would be nice to know what "something wrong" is.
Does the timer not start ?
Does it not expire ?
Does it not run for the set time ?
Or ?

The problem is that everything seems to be ok(as it was in OB1). I just don't understand why when I call my FB from OB35 and not from OB1 program does not work. Or maybe it is not the problem of the timers but variables. I start timers with FP(0->1) with static variables declared in FB where the timers are.

Martin, you still haven't really answered Jesper's question. How do you know that the program is'nt working - what isn't happening that should happen, or what is happening that shouldn't?

Post your code.
Also, is the problem that the timer does not start ? Or... ?

So, working program should wait 1 second after motor achieves desired position and than the motor should be started in other direction, and after also 1 sec(count other timer) after one output is set the other output should be reset.
When FB is in OB35 motor is immediately started after it achieves the position(motor in level) and outputs is also immediately reset.

here is the code of my FB:

FUNCTION_BLOCK FB 52
TITLE =
VERSION : 0.1

VAR
StartFromBottom : BOOL ;
GoDown : BOOL ;
OnBottom : BOOL ;
GO_1 : BOOL ;
GO_2 : BOOL ;
Start : BOOL ;
GO_3 : BOOL ;
StartEdge : BOOL ;
DoneEdge : BOOL ;
Busy : BOOL ;
go_down : BOOL ;
PosNo : INT := 1;
PCylinder : BOOL ;
Timer1 : BOOL ;
T1_out : BOOL ;
T2_out : BOOL ;
TimerF : BOOL ;
Timer2F : BOOL ;
Timer2 : BOOL ;
UnLoad : BOOL ;
UnLoad0 : BOOL ;
UnLoad1 : BOOL ;
UnLoad2 : BOOL ;
UnLoad3 : BOOL ;
PosLevel1 : INT ;
PosLevel2 : INT ;
PosLevel3 : INT ;
PosLevel4 : INT ;
PosBottom : INT ;
END_VAR
VAR_TEMP
PosPointer : DWORD ;
OrderPointer : DWORD ;
StockPointer : DWORD ;
END_VAR
BEGIN
NETWORK
TITLE =Choose position
U #go_down;
FP #GO_2;
SPB M006;
U "MOrderFound"; //jezeli znalizlismy 1 w tablicy
FP #GO_1;
SPB M001;
U #Busy;
SPB Done;
M006: L 6; //Pos=bottom
T #PosNo;
S #Busy;
SPA SET;
M001: S #Busy;
SPA SET;
//*** Travel order finished?
Done: U "DB_M_Abs1".Done;
FP #DoneEdge;
R "DB_M_Abs1".Execute;
SPBN NDon; // Jump if no DONE
//*** Start evaluation
NDon: UN "MAutomatik_Manual";
SPB Manu;
S "DB_M_Abs1".Execute;
FP #StartEdge;
SPBN Manu; // Jump if no restart
Manu: U "DB_M_Abs1".Execute;
FP #StartEdge;
SPBN EMC; // Jump if no restart
//*** The position number is valid, so travel to this position!
// Calculate the addresses of position and velocity suitable for this position number in
// DB_POS_05, read their values and transfer to FB MoveAbsolute.
SET: L #PosNo;
SLW 3; // Adr_Position = PosNo x 8 - 6
L 6;
-I ;
SLW 3; // and read position value
T #PosPointer;
AUF "DB_POS_05"; // into pointer format
L DBD [#PosPointer];
T "DB_M_Abs1".Position; // Transfer position to FB
L #PosPointer; // the velocity
L P#4.0; // is in the DB behind
+D ; // the position
T #PosPointer;
AUF "DB_POS_05"; // read velocity
L DBD [#PosPointer];
T "DB_M_Abs1".Velocity; // transfer velocity to FB
EMC: NOP 0;
NETWORK
TITLE =Check where the lift is
CALL "WhichPosition" , DB 9 (
PosLevel1 := 100,
PosLevel2 := 200,
PosLevel3 := 300,
PosLevel4 := 400,
PosBottom := 0,
OnLevel1 := "MLevel1",
OnLevel2 := "MLevel2",
OnLevel3 := "MLevel3",
OnLevel4 := "MLevel4",
Bottom := "MBottom");

NETWORK
TITLE =Check if there is request to go (1 in DB2)
CALL "CheckGoRequest" , DB 57 (
Search := "MSearchForOrder",
LevelToGo := "MOrderinLevel",
OneFound := "MOrderFound");

NETWORK
TITLE =Start searching for order
U "CylinderBottom";
FN #OnBottom;
O( ;
U( ;
O "ELoadBlockLevel4";
O "ELoadBlockLevel3";
O "ELoadBlockLevel2";
O "ELoadBlockLevel1";
) ;
FP #Start;
) ;
R "MOrderFound";
= "MSearchForOrder";
NETWORK
TITLE =Check if the lift is on the desired position
CALL "OnPosition" , DB 58 (
PosNo := #PosNo,
OnPosition := "MLiftOnBottom");
U "MLiftOnBottom";
FP #GoDown;
SPBN NDow;
S #Timer2;
SPA OnBo;
NDow: U "MBottom";
FP #GO_3;
SPBN OnBo;
S #Timer1;
S "CylinderBottom";
R #go_down;
OnBo: NOP 0;
NETWORK
TITLE =
U "MLevel1";
= "ALevel1";
NETWORK
TITLE =
U "MLevel2";
= "ALevel2";
NETWORK
TITLE =
U "MLevel3";
= "ALevel3";
NETWORK
TITLE =
U "MLevel4";
= "ALevel4";
NETWORK
TITLE =
U "MBottom";
= "ABottom";
NETWORK
TITLE =Activate pneumatic cylinders

L "MOrderinLevel";
T #PosNo;
U "MLiftOnBottom";
SPBN ENDC;
L 1;
==I ;
SPBN C2;
S "CylinderLevel1";
S #Timer1;
SPA ENDC;
C2: L #PosNo;
L 2;
==I ;
SPBN C3;
S "CylinderLevel2";
S #Timer1;
SPA ENDC;
C3: L #PosNo;
L 3;
==I ;
SPBN C4;
S "CylinderLevel3";
S #Timer1;
SPA ENDC;
C4: L #PosNo;
L 4;
==I ;
SPBN ENDC;
S "CylinderLevel4";
S #Timer1;
SPA ENDC;

ENDC: NOP 0;
NETWORK
TITLE =Start timer1
U #Timer1;
L S5T#1S;
SE T 1;
U #T1_out;
R T 1;
NOP 0;
NOP 0;
U T 1;
= #T1_out;
// U #Timer1
// = L 12.0
// BLD 103
// U #T1_out
// = L 12.1
// BLD 103
// CALL "Timer" , DB16
// TimerNR :=T1
// TimeToGo :=S5T#1S
// StartTimer:=L12.0
// ResetTimer:=L12.1
// Done :=#T1_out
// NOP 0
NETWORK
TITLE =When T1_out 0->1 then reset cylinders
U #T1_out;
FP #TimerF;
SPBN TEND;
R #Timer1;
R "CylinderLevel1";
R "CylinderLevel2";
R "CylinderLevel3";
R "CylinderLevel4";
R "CylinderBottom";
TEND: NOP 0;
NETWORK
TITLE =Start Timer2
U #Timer2;
L S5T#1S;
SE T 2;
U #T2_out;
R T 2;
NOP 0;
NOP 0;
U T 2;
= #T2_out;
// U #Timer2
// = L 12.0
// BLD 103
// U #T2_out
// = L 12.1
// BLD 103
// CALL "Timer" , DB17
// TimerNR :=T2
// TimeToGo :=S5T#1S
// StartTimer:=L12.0
// ResetTimer:=L12.1
// Done :=#T2_out
// NOP 0
NETWORK
TITLE =When T2_out 0->1 go down
U #T2_out;
FP #Timer2F;
SPBN T2EN;
R #Timer2;
S #go_down;
T2EN: NOP 0;
NETWORK
TITLE =
U "CylinderBottom";
FN #UnLoad;
SPBN ULoa;
R "BlockOnPlatform";
ULoa: NOP 0;
NETWORK
TITLE =
U "CylinderLevel4";
FN #UnLoad0;
SPBN UL1;
S "BlockOnPlatform";
R "BlockOnLevel4";
UL1: NOP 0;

NETWORK
TITLE =
U "CylinderLevel3";
FN #UnLoad1;
SPBN UL2;
S "BlockOnPlatform";
R "BlockOnLevel3";
UL2: NOP 0;

NETWORK
TITLE =
U "CylinderLevel2";
FN #UnLoad2;
SPBN UL3;
S "BlockOnPlatform";
R "BlockOnLevel2";
UL3: NOP 0;

NETWORK
TITLE =
U "CylinderLevel1";
FN #UnLoad3;
SPBN UL4;
S "BlockOnPlatform";
R "BlockOnLevel1";
UL4: NOP 0;
END_FUNCTION_BLOCK

Note that posting code in symbolic format requires a lot of work to cut/paste into Step7, compile it and try it!

We cannot compile it when we dont have the symbols.
"MLiftOnBottom" must be a merker I think.
It activates one of the timers in there. But is it the one in question ?
I dont want to understand the whole program, just what is relevant to your problem.
It is not easy to follow when you have two BOOL STATs one is "GoDown" and the others is "go_down". And there are BOOL STATs that are called #Timer1 and #Timer2.

Can you steer us closer to which timers you are talking about ?