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Topics - congo

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Technical support / Method for causing events at counter PV intervals
« on: April 17, 2018, 02:44:12 PM »
I'm looking for a method to trigger a math equation at intervals of a HSCPV[n] as it accumulates.

For instance, as the counter accumulates 100 counts, solve the math equation, then after another 100 counts solve it again, continue to do this after each 100 counts until the HSCPV[n] is reset from a separate part of the program. The counter does not stop at any point so the equation trigger needs to happen 'on the fly'.

One method I thought might work would be to use an IF statement. IF HSCPV[n]/100=1 THEN (equation here) ENDIF. The 1 could be incremented at each TRUE occurrence of the if statement. But even if the custom function rung clock is set fast at 0.01s it still seems to miss the IF instruction.

I'm sure there's a better way...

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Technical support / PID negative saturation
« on: March 30, 2018, 01:11:21 PM »
When setting lmt in 'PIDdef ch,lmt, P,I,D' statement how is the negative part of the controller output usually handled? If the computed result drives the controller output all the way to its max negative value (i.e -100) there is an undesirable time delay for the controller to get back from -100 to 0 and then respond in the positive portion of its output.

In my example the PIDcompute(1,n), n is a scaled 0-100% value which is then further scaled to 0-4096 intended for a DAC output. When the controller cuts back the output it inevitably passes zero and hits -100 where my problem exists. I've tried scaling (Input-(-100)/200 so that the controller output scales the total lmt span of 200 from -100 to +100. Not sure if this is an effective way to handle this though?

3
Technical support / DAC stability
« on: March 26, 2018, 01:48:38 PM »
When a DAC output is set to a value, and not moving when viewed by online monitor, why would the output voltage level move around? The output is connected to a 0-10V motorised valve actuator input and a signal fluctuation of about +/- 0.02V is seen constantly. The 0.2% movement is enough to hear the valve actuator hunting constantly. Is there a way to reduce this effect?

4
Technical support / PWM output
« on: February 14, 2017, 01:16:38 PM »
An older post referred to using the IRF530 mosfet as a means to increase the amperage when switching larger loads, the response was to use an SSR. My expierience with this is that most puck style SSR I've tested are too slow and created excessive heat in the motor and poor control. Does anyone have any hardware suggestions for using the NANO PWM output to drive a 12VDC motor up to 7 amps?  

5
Technical support / CANBUS
« on: May 21, 2016, 05:57:57 AM »
Are the FX series CANBUS capable now? If so, where is the supporting documentation found for programming and using the protocol with the PLCs?

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Technical support / Save value from slave during power loss
« on: April 29, 2016, 10:44:10 AM »
If a slave PLC is being read by the master (via MB) and the slave loses power without backup memory installed, does anyone have a suggestion for saving the last good DM[] value in the master PLC?

For instance if a counter value (in slave PLC) is being read by the master into DM[] when the slave suddenly loses power the current number of counts is lost. Could a line of code be written to capture the counts continously but keep the last good value in this situation? Is there a code solution to this rather than installing extra memory in all the slaves?

Thanks.

7
Technical support / Count pulses on pulse frequency inputs
« on: April 22, 2016, 12:14:31 PM »
Can someone tell me what the best way is to capture the accumulated number of pulses on a PULSEFREQUENCY[] channel.

I'm using the input channels to measure rotating frequency of a conveyor but would also like to capture the number of pulses on that same channel.

8
Technical support / Web browser greyed out
« on: December 18, 2015, 12:12:30 PM »
I modified the .HTM file according to what I needed for interface to Fmd88-10 via iphone/ipad on a wireless network. All seems well except now when connecting with anything except iphone everything on the faceplate is completely background grey, no buttons or lcd etc. However connecting with iphone the interface is fully functioning and appears as expected. Not sure what the problem could be to allow normal browser  with an iphone but abnormal with ipad? Tried a few devices to rule out one particular device issue. Thanks.

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Technical support / FMD comms to HMi
« on: December 01, 2015, 05:55:15 AM »
Does the FMD series work with the 'HMi draw' native app? I'm attempting a TCP/IP connection and this program looks for a validation code in the comms setup. Haven't been able to make the Plc connection with it so far. Thanks.

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