FM COUNTER MODULE

Transcription

1 FM COUNTER MODULE Function The FM off-loads the CPU by: Direct connection of incremental encoders Direct connection for gate signals (light barrier etc.) using integrated digital inputs. A comparison function and output of response using integrated digital output modules. The following functions are provided: 1 channel for upcounting and downcounting; 32 bit Counting frequency up to 500 khz (RS 422 encoders) Counting range 0 to 32 bit or +/- 31 bit, as required One-shot or periodic counting process 1-, 2- or 4-fold evaluation Incremental encoder can be connected Gate control via levels, pulses or software control Setting via the digital input Counter can be loaded with a predefined starting value Comparison function using two selectable comparison values Page 1158 Mar 2008 Siemens ITS

2 Interrupt response when a comparison value is reached, zero crossing, range violation (selectable) Output signal (24 V-level) that the comparison function controls: With jointly selectable pulse duration or as a continuous signal from the comparison value to the limit of the counting range. Standard Function Blocks CNT_CTRL (FC 0) For controlling the counters of the FM DIAG_INF (FC 1) For providing the diagnostic information of the FM Mode of operation The FM counter module detects pulses from incremental encoders at up to 500 khz, as a function of directly connectable gate signals. It evaluates the direction of the pulses and compares the actual value with two comparison values, which can be preset.there are two possibilities available to output the reaction to the process: 2 digital outputs; they can be configured using the selectable minimum pulse or with level switching. Backplane bus; the FM can send an alarm signal to the CPU via the integrated backplane bus. Page 1159 Mar 2008 Siemens ITS

3 Operating Modes Continuous counting One-shot counting Periodic counting After the gate is enabled, endless counting takes place between the lower and upper count limit from the starting value After the gate is enabled, the system counts once from the starting value to the upper or lower limit depending on the main count direction Main counting direction up: from 0 to the programmable range limit Main counting direction down: from the programmable start value to 0 After the gate is enabled, periodic counting takes place from the starting value within the programmed counting range depending on the main count direction Main counting direction up: periodic from 0 to the programmed range limit 1 Main counting direction down: periodically from the programmed start value to 1 Parameterization Parameters are assigned with STEP 7 with the help of parameterization screen forms. A configuring package is available for this purpose. Technical specifications Page 1160 Mar 2008 Siemens ITS

4 Technical specifications Supply voltage Aux. voltage 1L+, load voltage 2 L+ Rated value (DC) Permissible range (ripple included) dynamic, lower limit (DC) dynamic, upper limit (DC) static, lower limit (DC) static, upper limit (DC) non-periodic skip Duration Recovery time Value Input current 6ES AH03-0AE0 24 V 18.5 V 30.2 V 20.4 V 28.8 V 500 ms 50 s 35 V Page 1161 Mar 2008 Siemens ITS

5 from load voltage 1L+ (without load), max. 40 ma from backplane bus 5 V DC, max. 160 ma Encoder supply 5 V encoder supply 5 V Yes; 5.2 V +/-2% Output current, max. 300 ma 24 V encoder supply 24 V Yes; 1L+ (-3 V) Output current, max. 400 ma Power losses Power loss, typ. 4.5 W Digital inputs Number/binary inputs 3 Functions 1 for gate start, 1 for gate stop, 1 for setting the counter Input voltage for signal "0" to +5 V for signal "1" +11 to V Input current for signal "1", typ. 9 ma Digital outputs Number/binary outputs 2 Functionality/short-circuit strength Yes; Clocked electronically Limitation of inductive shutdown voltage to 2L+ (-39 V) Page 1162 Mar 2008 Siemens ITS

6 Output voltage for signal "0" (DC), max. 3 V for signal "1", min. 2L+ (-1.5 V) Output current for signal "1" rated value 0.5 A for signal "1" permissible range for 0 to 5 ma 60 C, min. for signal "1" permissible range for 0 to 0.6 A 60 C, max. Output delay with resistive load 0 to "1", max. 300 µs Encoder Connectable encoders Incremental encoder (symmetrical) Yes; With 2 pulse trains offset by 90 Incremental encoder (asymmetrical) Yes 24 V initiator Yes 24 V directional element Yes; 1 pulse train, 1 direction level Counter Number of counter inputs 1 Counting range, description 32 bit or +/-31 bit Minimum pulse width, adjustable Yes; 2.5 or 25 µs Counter input 5 V Type RS 422 Terminating resistor 220 Ω Page 1163 Mar 2008 Siemens ITS

7 Differential input voltage Counting frequency, max. Counter input 24 V Input voltage, for signal "0" Input voltage, for signal "1" Input current, for signal "1", typ. Counting frequency, max. Minimum pulse width 2.5 µs Galvanic isolation Galvanic isolation digital inputs between the channels and the backplane bus Galvanic isolation digital outputs between the channels and the backplane bus Galvanic isolation counter between the channels and the backplane bus Permissible potential difference between different circuits Isolation Isolation checked with Connection method required front connector 1.3 V 500 khz to +5 V +11 to V 9 ma 200 khz Yes; Optocoupler Yes; Optocoupler Yes; Optocoupler 75 VDC / 60 VAC 500 V 1x 20-pin Page 1164 Mar 2008 Siemens ITS