FM COUNTER MODULE

Transcription

1 FM COUNTER MODULE Function The module takes the load off the CPU by: direct connection of 24 V incremental encoders, direction encoders, initiators and NAMUR sensors. direct connection for gate signals (e.g. light barrier) via integral digital inputs. comparison function and output of response via integral digital outputs. The following functions are available: 8 channels for up and down counting; 32 bit Counting/measuring frequency up to 10 khz (for 24 V incremental encoders), up to 20 khz (for 24 V direction encoders, 24 V initiators, NAMUR sensors) Counting range + 31 bit Counting: continuous, once-only or periodic Measuring: frequency, speed, period Dosing 1-, 2- or 4-fold evaluation For connection of incremental encoders; 24 V encoders, direction encoders, initiators and NAMUR sensors Gate control via level at digital input (HW gate) as well as software control (SW gate) Loading of counters with defined starting values Comparison functions with definable comparison values Alarm response on reaching a comparison value or on exceeding a range Output signal (24 V level), controlled by the comparison function: as continuous signal from comparison value up to limit of counting range Page 1165 Mar 2008 Siemens ITS

2 Standard function blocks CNT2_CTR (FC 2) Control of software gates and digital outputs of the FM CNT2_WR (FC 3) CNT2_WRPN (FB 3) CNT2_RD (FC 4) CNT2_RDPN (FB4) Write counter values, limits and comparison values to the FM Read out current count and measurement values from the FM (for four channels each) DIAG_RD (FC 5) for provision of diagnostics information of the FM in event of diagnostics interrupt Operating principle The SIPLUS FM counter module records the pulses from 24 V incremental encoders, direction encoders, initiators and NAMUR sensors depending on directly connectable gate signals. It compares the counted value with the defined comparison values in both counting directions. The FM provides seven different operating modes for fast and simple adaptation to the desired application. With the exception of the "dosing" operating mode, all channels can be used independently in any operating mode: Page 1166 Mar 2008 Siemens ITS

3 Operating modes Continuous counting Count once After the gate has been enabled, counting is performed continuously (beginning with the starting value) between the upper and lower limits. After the gate has been enabled, counting is performed once (beginning at the starting Page 1167 Mar 2008 Siemens ITS

4 Periodic count value) to the upper or lower limit depending on the main count direction. Main count direction upwards: from 0 up to the parameterizable full-scale value Main count direction downwards: from the parameterizable start-of-scale value down to 0 After the gate has been enabled, counting is performed periodically (beginning at the starting value) within the parameterized counting range depending on the main count direction. Frequency counting Main count direction upwards: periodically from 0 up to the parameterizable full-scale value 1 Main count direction downwards: periodically from the parameterizable start-of-scale value down to 1 After the gate has been enabled, all the pulses received within a parameterizable time frame are counted and the frequency is determined from this. Page 1168 Mar 2008 Siemens ITS

5 Speed measurement Cycle duration measurement Dosing After the gate has been enabled, all the pulses received within a parameterizable time frame are counted and the speed is determined from this. After the gate has been enabled, all the pulses received within a parameterizable time frame are counted and the period is determined from this. 4 counter channels are combined to form one proportioning channel. After the gate has been enabled, proportioning is performed once (beginning at the starting value) to the upper or lower limit depending on the main count direction. Main count direction upwards: from 0 up to the parameterizable full-scale value Main count direction downwards: from the parameterizable start-of-scale value down to 0 Two possibilities are available for output of the response to the process: Digital outputs: a digital output is directly assigned to each counter channel to allow a fast response. Page 1169 Mar 2008 Siemens ITS

6 Backplane bus: the FM can send process interrupts to the CPU via the integral backplane bus. The following alternatives are available on failure of the CPU: Failure responses Cancellation Continue Switch to substitute value Keep last value Description The outputs are switched off immediately, the counting/measuring processes are canceled. The module continues counting/measuring unchanged, even after a restart of the CPU Active counting/measuring processes are cancelled. The module applies the configured substitute values at the outputs, channel by channel. Active counting/measuring processes are cancelled. The module's outputs are frozen in the state they had immediately before canceling. Parameter assignment Parameterization is performed with STEP 7 with use of the parameterization screen forms. A configuration package is available for this: Startup Page 1170 Mar 2008 Siemens ITS

7 4-page brief instructions are enclosed with the configuration package to allow fast and simple startup of the module, and lead to a functioning application in max. 1 hour by using a specific example. When doing this, the following steps must be taken into account: Prerequisites Installation of the configuration package on the programming device Installation and wiring of the FM Generation of the counter DB Parameterization of FM Integration into the user program Diagnostics A further example serves for orientation and adaptation to the desired application. Technical specifications Page 1171 Mar 2008 Siemens ITS

8 Technical specifications Supply voltage Aux. voltage 1L+, load voltage 2 L+ Rated value (DC) permissible range, lower limit (DC) permissible range, upper limit (DC) Input current from load voltage L+ (without load), max. 6ES AH01-0AE0 24 V 20.4 V 28.8 V 150 ma Page 1172 Mar 2008 Siemens ITS

9 from backplane bus 5 V DC, max. 100 ma Encoder supply Output voltage NAMUR-encoder supply: 8.2 V +/-2% Output current, rated value 200 ma Output current Short-circuit protection Yes Power losses Power loss, typ. 10 W Digital inputs Number/binary inputs 8 Functions 1 each for gate start/ gate stop Input voltage for signal "0" -3 to +5 V for signal "1" 11 to 30.2 V Input current for signal "0", max. (permissible quiescent 2 ma current) for signal "1", typ. 9 ma Input delay (for rated value of input voltage) for standard inputs 50 µs at "0" to "1", max. Cable length Cable length, shielded, max. 100 m Page 1173 Mar 2008 Siemens ITS

10 Digital outputs Number/binary outputs 8 Functionality/short-circuit strength Yes Limitation of inductive shutdown voltage to L+ (-40 V) Output voltage for signal "1", min. L+ (-0.8 V) Output current for signal "1" rated value 0.5 A for signal "0" residual current, max. 0.5 ma Output delay with resistive load 0 to "1", max. 300 µs Switching frequency with resistive load, max. 500 Hz with inductive load, max. 0.5 Hz Aggregate current of outputs (per group) horizontal installation 4 A up to 40 C, max. 2 A up to 60 C, max. all other mounting positions 2 A up to 40 C, max. Cable length Page 1174 Mar 2008 Siemens ITS

11 Cable length, shielded, max. 600 m Cable length unshielded, max. 100 m Encoder Connectable encoders Incremental encoder (asymmetrical) Yes 24 V initiator Yes 24 V directional element Yes NAMUR encoder Yes 2-wire BEROS Yes NAMUR encoder Number of NAMUR inputs 8 Input signal to DIN Input current, for signal "0", max. 1.2 ma Input current, for signal "1", min. 2.1 ma Input delay, max. 50 µs Input frequency, max. 20 khz Cable length, shielded, max. 100 m Interrupts/diagnostics/status information Alarms Diagnostic alarm Yes; Parameterizable Hardware interrupt Yes; Parameterizable Diagnoses Diagnostic functions Yes; Diagnostic information readable Counter Page 1175 Mar 2008 Siemens ITS

12 Counter input 24 V Number 8; 32 bit or +/-31 bit Input voltage, for signal "0" -3 to +5 V Input voltage, for signal "1" 11 to 30.2 V Input current, for signal "0", max. 2 ma (permissible quiescent current) Input current, for signal "1", typ. 9 ma Input delay, max. 50 µs Counting frequency, max. 20 khz; Incremental encoder: 10 khz Cable length, max. 100 m Galvanic isolation Galvanic isolation digital inputs between the channels and the backplane Yes; and shielding bus between the channels and the backplane yes, against backplane bus and shielding bus (NAMUR) Galvanic isolation digital outputs between the channels and the backplane Yes; and shielding bus Galvanic isolation counter between the channels and the backplane Yes; and shielding bus Connection method required front connector 1x 40-pin Page 1176 Mar 2008 Siemens ITS