Ladder Logic (lad) for S7-300 and S7-400 Programming
BR ---| |--- Exception Bit Binary Result
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12.5 BR ---| |--- Exception Bit Binary Result Symbol or negation / BR BR Description BR ---| |--- (Exception Bit BR Memory) or BR ---| / |--- (Negated Exception Bit BR Memory) contact symbols are used to test the logic state of the BR bit in the status word. Used in series, the result of the scan is linked to the RLO by AND, used in parallel, it is linked to the RLO by OR. The BR bit is used in the transition from word to bit processing. Status word BR CC 1 CC 0 OV OS OR STA RLO /FC writes: - - - - - x x x 1 Example I 0.0 BR I 0.2 S Q 4.0 Q4.0 is set if I0.0 is "1" or I0.2 is "0" and in addition to this RLO the logic state of the BR bit is "1". Status Bit Instructions 12.6 ==0 ---| |--- Result Bit Equal 0 Ladder Logic (LAD) for S7-300 and S7-400 Programming Reference Manual, 04/2017, A5E41524738-AA 147 12.6 ==0 ---| |--- Result Bit Equal 0 Symbol or negation / ==0 ==0 Description ==0 ---| |--- (Result Bit Equal 0) or ==0 ---| / |--- (Negated Result Bit Equal 0) contact symbols are used to recognize if the result of a math function is equal to "0". The instructions scan the condition code bits CC 1 and CC 0 in the status word in order to determine the relation of the result to "0". Used in series, the result of the scan is linked to the RLO by AND, used in parallel, it is linked to the RLO by OR. Status word BR CC 1 CC 0 OV OS OR STA RLO /FC writes: - - - - - x x x 1 Examples SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 ==0 S Q 4.0 The box is activated by signal state "1" at I0.0. If the value of IW0 is equal to the value of IW2, the result of the math function "IW0 - IW2" is "0". Q4.0 is set if the function is properly executed and the result is equal to "0". SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 ==0 S Q 4.0 Q4.0 is set if the function is properly executed and the result is not equal to "0". Status Bit Instructions 12.7 <>0 ---| |--- Result Bit Not Equal 0 Ladder Logic (LAD) for S7-300 and S7-400 Programming 148 Reference Manual, 04/2017, A5E41524738-AA 12.7 <>0 ---| |--- Result Bit Not Equal 0 Symbol or negation / <>0 <>0 Description <>0 ---| |--- (Result Bit Not Equal 0) or <>0 ---| / |--- (Negated Result Bit Not Equal 0) contact symbols are used to recognize if the result of a math function is not equal to "0". The instructions scan the condition code bits CC 1 and CC 0 in the status word in order to determine the relation of the result to "0". Used in series, the result of the scan is linked to the RLO by AND, used in parallel, it is linked to the RLO by OR. Status word BR CC 1 CC 0 OV OS OR STA RLO /FC writes: - - - - - x x x 1 Examples SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 <>0 S Q 4.0 The box is activated by signal state "1" at I0.0. If the value of IW0 is different to the value of IW2, the result of the math function "IW0 - IW2" is not equal to "0". Q4.0 is set if the function is properly executed and the result is not equal to "0". SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 <>0 S Q 4.0 Q4.0 is set if the function is properly executed and the result is equal to "0". Status Bit Instructions 12.8 >0 ---| |--- Result Bit Greater Than 0 Ladder Logic (LAD) for S7-300 and S7-400 Programming Reference Manual, 04/2017, A5E41524738-AA 149 12.8 >0 ---| |--- Result Bit Greater Than 0 Symbol or negation / >0 >0 Description >0 ---| |--- (Result Bit Greater Than 0) or >0 ---| / |--- (Negated Result Bit Greater Than Zero) contact symbols are used to recognize if the result of a math function is greater than "0". The instructions scan the condition code bits CC 1 and CC 0 in the status word in order to determine the relation to "0". Used in series, the result of the scan is linked to the RLO by AND, used in parallel, it is linked to the RLO by OR. Status word BR CC 1 CC 0 OV OS OR STA RLO /FC writes: - - - - - x x x 1 Example SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 >0 S Q 4.0 The box is activated by signal state "1" at I0.0. If the value of IW0 is higher than the value of IW2, the result of the math function "IW0 - IW2" is greater than "0". Q4.0 is set if the function is properly executed and the result is greater than "0". SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 >0 S Q 4.0 Q4.0 is set if the function is properly executed and the result is not greater than "0". Status Bit Instructions 12.9 <0 ---| |--- Result Bit Less Than 0 Ladder Logic (LAD) for S7-300 and S7-400 Programming 150 Reference Manual, 04/2017, A5E41524738-AA 12.9 <0 ---| |--- Result Bit Less Than 0 Symbol or negation / <0 <0 Description <0 ---| |--- (Result Bit Less Than 0) or <0 ---| / |--- (Negated Result Bit Less Than 0) contact symbols are used to recognize if the result of a math function is less than "0". The instructions scan the condition code bits CC 1 and CC 0 in the status word in order to determine the relation of the result to "0". Used in series, the result of the scan is linked to the RLO by AND, used in parallel, it is linked to the RLO by OR. Status word BR CC 1 CC 0 OV OS OR STA RLO /FC writes: - - - - - x x x 1 Example SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 <0 S Q 4.0 The box is activated by signal state "1" at I0.0. If the value of IW0 is lower than the value of IW2, the result of the math function "IW0 - IW2" is less than "0". Q4.0 is set if the function is properly executed and the result is less than "0". SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 <0 S Q 4.0 Q4.0 is set if the function is properly executed and the result is not less than "0". Status Bit Instructions 12.10 >=0 ---| |--- Result Bit Greater Equal 0 Ladder Logic (LAD) for S7-300 and S7-400 Programming Reference Manual, 04/2017, A5E41524738-AA 151 12.10 >=0 ---| |--- Result Bit Greater Equal 0 Symbol or negation / >=0 >=0 Description >=0 ---| |--- (Result Bit Greater Equal 0) or >=0 ---| / |--- (Negated Result Bit Greater Equal 0) contact symbols are used to recognize if the result of a math function is greater than or equal to "0". The instructions scan the condition code bits CC 1 and CC 0 in the status word in order to determine the relation to "0". Used in series, the result of the scan is linked to the RLO by AND, used in parallel, it is linked to the RLO by OR. Status word BR CC 1 CC 0 OV OS OR STA RLO /FC writes: - - - - - x x x 1 Example SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 >=0 S Q 4.0 The box is activated by signal state "1" at I0.0. If the value of IW0 is higher or equal to the value of IW2, the result of the math function "IW0 - IW2" is greater than or equal to "0". Q4.0 is set if the function is properly executed and the result is greater than or equal to "0". SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 >=0 S Q 4.0 Q4.0 is set if the function is properly executed and the result is not greater than or equal to "0". Status Bit Instructions 12.11 <=0 ---| |--- Result Bit Less Equal 0 Ladder Logic (LAD) for S7-300 and S7-400 Programming 152 Reference Manual, 04/2017, A5E41524738-AA 12.11 <=0 ---| |--- Result Bit Less Equal 0 Symbol or negation / <=0 <=0 Description <=0 ---| |--- (Result Bit Less Equal 0) or <=0 ---| / |--- (Negated Result Bit Less Equal 0) contact symbols are used to recognize if the result of a math function is less than or equal to "0". The instructions scan the condition code bits CC 1 and CC 0 in the status word in order to determine the relation of the result to "0". Used in series, the result of the scan is linked to the RLO by AND, used in parallel, it is linked to the RLO by OR. Status word BR CC 1 CC 0 OV OS OR STA RLO /FC writes: - - - - - x x x 1 Examples SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 <=0 S Q 4.0 The box is activated by signal state "1" at I0.0. If the value of IW0 is less than or equal to the value of IW2 the result of the math function "IW0 - IW2" is less than or equal to "0". Q4.0 is set if the function is well properly executed and the result is less than or equal to "0". SUB_I EN OUT IN2 ENO IN1 IW2 IW0 MW10 I 0.0 <=0 S Q 4.0 Q4.0 is set if the function is properly executed and the result is not less than or equal to "0". Ladder Logic (LAD) for S7-300 and S7-400 Programming Reference Manual, 04/2017, A5E41524738-AA 153 13 Timer Instructions 13.1 Overview of Timer Instructions Description - You can find information for setting and selecting the correct time under "Location of a Timer in Memory and Components of a Timer". The following timer instructions are available: • S_PULSE Pulse S5 Timer • S_PEXT Extended Pulse S5 Timer • S_ODT On-Delay S5 Timer • S_ODTS Retentive On-Delay S5 Timer • S_OFFDT Off-Delay S5 Timer • ---( SP ) Pulse Timer Coil • ---( SE ) Extended Pulse Timer Coil • ---( SD ) On-Delay Timer Coil • ---( SS ) Retentive On-Delay Timer Coil • ---( SA ) Off-Delay Timer Coil Timer Instructions 13.2 Location of a Timer in Memory and Components of a Timer Ladder Logic (LAD) for S7-300 and S7-400 Programming 154 Reference Manual, 04/2017, A5E41524738-AA 13.2 Location of a Timer in Memory and Components of a Timer Area in Memory Timers have an area reserved for them in the memory of your CPU. This memory area reserves one 16-bit word for each timer address. The ladderlogic instruction set supports 256 timers. Please refer to your CPU’s technical information to establish the number of timer words available. The following functions have access to the timer memory area: • Timer instructions • Updating of timer words by means of clock timing. This function of your CPU in the RUN mode decrements a given time value by one unit at the interval designated by the time base until the time value is equal to zero. Time Value Bits 0 through 9 of the timer word contain the time value in binary code. The time value specifies a number of units. Time updating decrements the time value by one unit at an interval designated by the time base. Decrementing continues until the time value is equal to zero. You can load a time value into the low word of accumulator 1 in binary, hexadecimal, or binary coded decimal (BCD) format. You can pre-load a time value using either of the following formats: • W#16#wxyz - Where w = the time base (that is, the time interval or resolution) - Where xyz = the time value in binary coded decimal format • S5T#a H_bM_cS_dMS - Where H = hours, M = minutes, S = seconds, and MS = milliseconds; a, b, c, d are defined by the user. - The time base is selected automatically, and the value is rounded to the next lower number with that time base. The maximum time value that you can enter is 9,990 seconds, or 2H_46M_30S. S5TIME#4S = 4 seconds s5t#2h_15m = 2 hours and 15 minutes S5T#1H_12M_18S = 1 hour, 12 minutes, and 18 seconds Timer Instructions 13.2 Location of a Timer in Memory and Components of a Timer Ladder Logic (LAD) for S7-300 and S7-400 Programming Reference Manual, 04/2017, A5E41524738-AA 155 Time Base Bits 12 and 13 of the timer word contain the time base in binary code. The time base defines the interval at which the time value is decremented by one unit. The smallest time base is 10 ms; the largest is 10 s. Time Base Binary Code for the Time Base 10 ms 00 100 ms 01 1 s 10 10 s 11 Values that exceed 2h46m30s are not accepted. A value whose resolution is too high for the range limits (for example, 2h10ms) is truncated down to a valid resolution. The general format for S5TIME has limits to range and resolution as shown below: Resolution Range 0.01 second 10MS to 9S_990MS 0.1 second 100MS to 1M_39S_900MS 1 second 1S to 16M_39S 10 seconds 10S to 2H_46M_30S Bit Configuration in the Time Cell When a timer is started, the contents of the timer cell are used as the time value. Bits 0 through 11 of the timer cell hold the time value in binary coded decimal format (BCD format: each set of four bits contains the binary code for one decimal value). Bits 12 and 13 hold the time base in binary code. The following figure shows the contents of the timer cell loaded with timer value 127 and a time base of 1 second: x x 1 0 15... ...8 7... ...0 0 0 0 1 0 0 1 0 0 1 1 1 1 2 7 Time value in BCD (0 to 999) Time base 1 second Irrelevant: These bits are ignored when the timer is started. Timer Instructions 13.2 Location of a Timer in Memory and Components of a Timer Ladder Logic (LAD) for S7-300 and S7-400 Programming 156 Reference Manual, 04/2017, A5E41524738-AA Reading the Time and the Time Base Each timer box provides two outputs, BI and BCD, for which you can indicate a word location. The BI output provides the time value in binary format. The BCD output provides the time base and the time value in binary coded decimal (BCD) format. Choosing the right Timer This overview is intended to help you choose the right timer for your timing job. t t t t t I 0.0 Q 4.0 S_PULSE Q 4.0 S_PEXT Q 4.0 S_ODT Q 4.0 S_ODTS Q 4.0 S_OFFDT Timer Description S_PULSE Pulse timer The maximum time that the output signal remains at 1 is the same as the programmed time value t. The output signal stays at 1 for a shorter period if the input signal changes to 0. S_PEXT Extended pulse timer The output signal remains at 1 for the programmed length of time, regardless of how long the input signal stays at 1. S_ODT On-delay timer The output signal changes to 1 only when the programmed time has elapsed and the input signal is still 1. S_ODTS Retentive on-delay timer The output signal changes from 0 to 1 only when the programmed time has elapsed, regardless of how long the input signal stays at 1. S_OFFDT Off-delay timer The output signal changes to 1 when the input signal changes to 1 or while the timer is running. The time is started when the input signal changes from 1 to 0. Timer Instructions 13.3 S_PULSE Pulse S5 Timer Ladder Logic (LAD) for S7-300 and S7-400 Programming Reference Manual, 04/2017, A5E41524738-AA 157 13.3 S_PULSE Pulse S5 Timer Symbol S_PULSE BI TV R BCD S_IMPULS DUAL TW S Q English German T no. T-Nr. S Q R DEZ Parameter English Parameter German Data Type Memory Area Description T no. T-Nr. TIMER T Timer identification number; range depends on CPU S S BOOL I, Q, M, L, D Start input TV TW S5TIME I, Q, M, L, D Preset time value R R BOOL I, Q, M, L, D Reset input BI DUAL WORD I, Q, M, L, D Remaining time value, integer format BCD DEZ WORD I, Q, M, L, D Remaining time value, BCD format Q Q BOOL I, Q, M, L, D Status of the timer Description S_PULSE (Pulse S5 Timer) starts the specified timer if there is a positive edge at the start (S) input. A signal change is always necessary in order to enable a timer. The timer runs as long as the signal state at input S is "1", the longest period, however, is the time value specified by input TV. The signal state at output Q is "1" as long as the timer is running. If there is a change from "1" to "0" at the S input before the time interval has elapsed the timer will be stopped. In this case the signal state at output Q is "0". The timer is reset when the timer reset (R) input changes from "0" to "1" while the timer is running. The current time and the time base are also set to zero. Logic "1" at the timer's R input has no effect if the timer is not running. The current time value can be scanned at the outputs BI and BCD. The time value at BI is binary coded, at BCD it is BCD coded. The current time value is the initial TV value minus the time elapsed since the timer was started. Timer Instructions 13.3 S_PULSE Pulse S5 Timer Ladder Logic (LAD) for S7-300 and S7-400 Programming 158 Reference Manual, 04/2017, A5E41524738-AA Timing Diagram Pulse timer characteristics: t t t t = Programmed time RLO at S input RLO at R input Timer running Scan for "1" Scan for "0" Status word BR CC 1 CC 0 OV OS OR STA RLO /FC writes: - - - - - x x x 1 Example S_PULSE S Q BI TV R BCD I 0.0 I 0.1 S5TIME#2S Q 4.0 T 5 If the signal state of input I0.0 changes from "0" to "1" (positive edge in RLO), the timer T5 will be started. The timer will continue to run for the specified time of two seconds (2 s) as long as I0.0 is "1". If the signal state of I0.0 changes from "1" to "0" before the timer has expired the timer will be stopped. If the signal state of input I0.1 changes from "0" to "1" while the timer is running, the time is reset. The output Q4.0 is logic "1" as long as the timer is running and "0" if the time has elapsed or was reset. Timer Instructions 13.4 S_PEXT Extended Pulse S5 Timer Ladder Logic (LAD) for S7-300 and S7-400 Programming Reference Manual, 04/2017, A5E41524738-AA 159 Yüklə 1,39 Mb. Dostları ilə paylaş:
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