http://forums.fieldbus.org/ Community forum related to the development and use of Foundation Fieldbus technology. en Thu, 17 May 2012 02:53:14 GMT vBulletin 60 http://forums.fieldbus.org/images/misc/rss.jpg http://forums.fieldbus.org/ http://forums.fieldbus.org/showthread.php?t=6503&goto=newpost Mon, 14 May 2012 22:04:47 GMT We installed a SMAR IF302 (3 input current to Fieldbus Device) on an existing DeltaV segment. We are trying to use two of the three inputs but the AI blocks are both stuck in OOS.

The blocks in the device are in AUTO and I have checked the Channels (1&2) and XD_Scale units (mA) seem to be correct. The rest of the segment is good.

I don't know if we have a spare to try but I am running out of ideas. Any suggestions for me to check/try in the morning.

-Mike ]]> solodiver2 http://forums.fieldbus.org/showthread.php?t=6503 http://forums.fieldbus.org/showthread.php?t=6495&goto=newpost Tue, 08 May 2012 03:07:15 GMT In a segment there is a single loop. An input device and a final control element device. In the function block application there are 3 FBs instantiated: AI, PID and AO. The AI runs in the measurement device and the PID and AO in the control valve positioner. Only 1 P/S VCR from the AI is... In a segment there is a single loop. An input device and a final control element device.
In the function block application there are 3 FBs instantiated: AI, PID and AO.
The AI runs in the measurement device and the PID and AO in the control valve positioner. Only 1 P/S VCR from the AI is scheduled plus each FBs execution time.
Can the AI announce C/S data while the PID or AO are being executed in the macrocyle? Or do C/S communication must happend once the last P/S VCR or FB has finished its execution (at the end of the macrocycle)? ]]> cris_control http://forums.fieldbus.org/showthread.php?t=6495 http://forums.fieldbus.org/showthread.php?t=6490&goto=newpost Wed, 25 Apr 2012 22:28:38 GMT 1.- How useful is to divide a macrocycle in subcycles? As an example a customer designed the segments with 1000ms macrocycle with individual FF applications (subcycles) per device. The AI (Input device) uses a FF application execution time of 1000ms meanwhile the PID and AO block (output... 1.- How useful is to divide a macrocycle in subcycles?

As an example a customer designed the segments with 1000ms macrocycle with individual FF applications (subcycles) per device. The AI (Input device) uses a FF application execution time of 1000ms meanwhile the PID and AO block (output device) run in a 500ms FF application execution time. The customer claims better response times by the PID. Which I do not totally believe.
In my way of understanding things I think the PID will only receive a new value to utilize in the calculations every second (AI subcycle 1000ms) so I do not think it is that useful.

Reading some bibliography having subcycles is not even recommended (mainly due to host limitations) but in my opinion all the devices that are part of the same loop should be in the same subcycle and different loops can have different subcycles within the same macrocycle for faster loops.

2.- For cases where the design is CIC, not CIF as above, whould this be useful? Being that the Host control application is not synchronized with the FF Application, having a faster Subcycle than the host IEC61131 control application execution time would improve the loop performance? ]]> cris_control http://forums.fieldbus.org/showthread.php?t=6490 http://forums.fieldbus.org/showthread.php?t=6483&goto=newpost Wed, 18 Apr 2012 15:06:24 GMT What advantage would a device with quicker function block (AI, DI, DO) execution times have over one with slower execution times? I assume the obvious answer is you will ultimately leave more free time for unscheduled transmissions and result in improve segment integrity. Is this assumption... What advantage would a device with quicker function block (AI, DI, DO) execution times have over one with slower execution times?

I assume the obvious answer is you will ultimately leave more free time for unscheduled transmissions and result in improve segment integrity. Is this assumption correct?

Thanks ]]> bhuber http://forums.fieldbus.org/showthread.php?t=6483 http://forums.fieldbus.org/showthread.php?t=6482&goto=newpost Wed, 18 Apr 2012 14:17:29 GMT Hello Everybody

I'am a newbee and I more related to other fieldbus system. Therefor I am look for any information regarding small host system, test equipment (hard and software) to build a FF-H1 test network with 2 upto 4 test devices.

Thanks for your help

With best regards,

DH ]]> dhomes http://forums.fieldbus.org/showthread.php?t=6482 http://forums.fieldbus.org/showthread.php?t=6476&goto=newpost Fri, 13 Apr 2012 18:44:13 GMT Hello, During some device testing a customer bumped into a problem where some parameters in the device were not working properly (wrong options in a combo box of the CHANNEL parameter). They compared the **.cff file of the malfunctioning device agains the *.cff file of the previous version and... Hello,

During some device testing a customer bumped into a problem where some parameters in the device were not working properly (wrong options in a combo box of the CHANNEL parameter). They compared the *.cff file of the malfunctioning device agains the *.cff file of the previous version and turned to be same, except the file dates. So they swaped the *.ffo files; they copied the *.ffo of the previous device version (which had always worked) and replaced the file of the newest device. They claim the device is now "working properly".

How much of a good solutions is this? How in the world were they even able to assign the device to the segment? Aren't they losing some functionality? ]]> cris_control http://forums.fieldbus.org/showthread.php?t=6476 http://forums.fieldbus.org/showthread.php?t=6470&goto=newpost Wed, 11 Apr 2012 15:04:52 GMT Hello everybody, I am looking a Fieldbus Foundation specification concerning the configuration and function of Control in the Field and Control in the controller. I could find information about these topics in white papers from manufacturers but not from Fieldbus Foundation directly. ... Hello everybody,

I am looking a Fieldbus Foundation specification concerning the configuration and function of Control in the Field and Control in the controller.

I could find information about these topics in white papers from manufacturers but not from Fieldbus Foundation directly.

Thank you in advance.

Luis Vela
End User ]]> luis.a.vela http://forums.fieldbus.org/showthread.php?t=6470 http://forums.fieldbus.org/showthread.php?t=6459&goto=newpost Thu, 05 Apr 2012 06:51:03 GMT Dear Experts, In one of our FF project requirement, Consultant has given the specification, as mentioned in “Wiring and installation 31.25 Kbit/s, voltage mode, wire medium”. As stated “ _For fieldbus use, a power supply impedance matching network is required_. This is the resistive... Dear Experts,

In one of our FF project requirement, Consultant has given the specification, as mentioned in “Wiring and installation 31.25 Kbit/s, voltage mode, wire medium”.

As stated “ For fieldbus use, a power supply impedance matching network is required. This is the resistive /inductive network that is either external or built into the field bus power supply”.

Could you please explain me , what is power supply impedance matching network?

Which FF power supply vendors offering a power supply meeting such requirements?

Thanks in advance,
Mani ]]> manik http://forums.fieldbus.org/showthread.php?t=6459 http://forums.fieldbus.org/showthread.php?t=6458&goto=newpost Thu, 05 Apr 2012 06:45:58 GMT Hello, I am trying to understand the Control in the Field configuration but I still have some doubts 1. If BLAS is enabled on more than one Field device, which one takes the control when the host drops? 2. How many control loops can be configured in a segment? Must I configure a LAS... Hello,

I am trying to understand the Control in the Field configuration but I still have some doubts

1. If BLAS is enabled on more than one Field device, which one takes the control when the host drops?

2. How many control loops can be configured in a segment? Must I configure a LAS for each control loop?

Thank you in advance for your comments.

Luis Vela
End User
]]> luis.a.vela http://forums.fieldbus.org/showthread.php?t=6458 http://forums.fieldbus.org/showthread.php?t=6455&goto=newpost Wed, 04 Apr 2012 01:20:15 GMT Has anybody implemented wireless HSE in a production system? I heard that one oil company already implemented wireless HSE and CIF in a "controlled environment" (it was a laboratory). The results are confidential and could not get anything else, yet I am sure they are not the only ones with that idea :eek:. This is not the WIO that the FOUNDATION announced last year. It is my understanding that the WIO is meant as interface between WirelessHART and ISA100.11a and the FF infrastructure. Please correct me if I am wrong. ]]> cris_control http://forums.fieldbus.org/showthread.php?t=6455 http://forums.fieldbus.org/showthread.php?t=6454&goto=newpost Tue, 03 Apr 2012 04:05:30 GMT Dear Experts, I have a following queries on FF segment calculations. In one of our project we have designed a segment with 8 devices (8 AI and 2 AO ). This two PID loops have been controlled by CIC with 1000 ms macro cycle. Now the customer is looking for a CIF solution. Dear Experts,

I have a following queries on FF segment calculations.

In one of our project we have designed a segment with 8 devices (8 AI and 2 AO ).

This two PID loops have been controlled by CIC with 1000 ms macro cycle.

Now the customer is looking for a CIF solution.

Here my doubt is, if we are implementing the CIF with the same 1000ms, can we accommodate the same 8AI and 2 AO devices in the same segment?

As per my understanding, if we are implementing the CIF then the latency time will be reduced and the same time number of devices in the loop also will be reduced.

Kindly comment me on my above mentioned queries.

Thanks in advance
Mani
]]> manik http://forums.fieldbus.org/showthread.php?t=6454 http://forums.fieldbus.org/showthread.php?t=6452&goto=newpost Fri, 30 Mar 2012 04:47:06 GMT Hi All Is there any tool or kit available to check the Configured Sessions , Configured VCRs, Automatic Sessions, Automatic VCRs and Republishings maximum limit in any HOST or Device?? or its mentioned some where in DD files?? Need to know how to verify these no.s?? Thanks Satish Kumar Hi All

Is there any tool or kit available to check the Configured Sessions , Configured VCRs, Automatic Sessions, Automatic VCRs and Republishings maximum limit in any HOST or Device?? or its mentioned some where in DD files??
Need to know how to verify these no.s??

Thanks
Satish Kumar ]]> satishkumar0085 http://forums.fieldbus.org/showthread.php?t=6452 http://forums.fieldbus.org/showthread.php?t=6451&goto=newpost Fri, 30 Mar 2012 03:47:22 GMT Hello, Supposing that the communication protocol to the HMI was OPC and we were performing control in the field, what is the recommended scan rate for the OPC DA Server/Client? Hello,

Supposing that the communication protocol to the HMI was OPC and we were performing control in the field, what is the recommended scan rate for the OPC DA Server/Client? ]]> cris_control http://forums.fieldbus.org/showthread.php?t=6451