Triconex AO Card Alarm with DVC 6030 Positioner

Hi,
At the facility there is Triconex Tricon System (v10.6) as an ESD system for the Plant. The Shutdown valve is equipped with a solenoid valve and the positioner (Fisher DVC 6030). The Solenoid is powered through a DO card and positioner through an AO card in the Tricon. The Tricon is intermittently giving "External Mismatch Error" for the AO card (3805H) in the Diagnostic and when this alarm appears the AO card goes into fault.

When consulted with Schneider, they came back with the reply as this being due to an external error, meaning some problem in the loop outside the Tricon. So, following steps were taken to check the loop:

1. Check the wiring from the Termination Board to the Positioner.
2. Positioner was checked with the Hart communicator, but that isn't showing any diagnostic error.
3. Even AO card was replaced with the spare new one.

Even now, the alarm is appearing intermittently.

We are still following up with the Schneider to know how does the card generated an alarm, meaning what does the card see in the two wires connected to it that it generates an alarm. Till now what we have received is that the 3 legs inside the Ao module see each other and and based on the mismatch the error is flagged.

However, this doesn't lead to anything that we can validate in the loop, be it in terms of current, voltage or resistance.

Has anybody came across such an alarm and have been able to diagnose, would like to share their experience?
 
Reading your post made me yearn for the days when manuals had a 'theory of operation' that described what you're looking for: a description of how the fault alarm is generated.

I have zero knowledge of Triconex, but I do know that some SIL 2 controllers monitor an AO to determine
- if the AO' loop is complete (no open circuit) and
- that the AO's current is within some band of what the demand signal says it should be.

You might check the loop for the obvious - a junction box where a loose connection could cause a momentary open that the AO card's internal diagnostics catch and generate a fault.

One time I found an intermittent on a device with screw clamp connectors where the connector was screwed down tight, but the wire had been inserted under/outside the screw clamp and the installer had never tugged on the wire to make sure it was 'inside' the screw clamp, not outside.

Please let us know how you resolve this situation.
 
Hi,
At the facility there is Triconex Tricon System (v10.6) as an ESD system for the Plant. The Shutdown valve is equipped with a solenoid valve and the positioner (Fisher DVC 6030). The Solenoid is powered through a DO card and positioner through an AO card in the Tricon. The Tricon is intermittently giving "External Mismatch Error" for the AO card (3805H) in the Diagnostic and when this alarm appears the AO card goes into fault.

When consulted with Schneider, they came back with the reply as this being due to an external error, meaning some problem in the loop outside the Tricon. So, following steps were taken to check the loop:

1. Check the wiring from the Termination Board to the Positioner.
2. Positioner was checked with the Hart communicator, but that isn't showing any diagnostic error.
3. Even AO card was replaced with the spare new one.

Even now, the alarm is appearing intermittently.

We are still following up with the Schneider to know how does the card generated an alarm, meaning what does the card see in the two wires connected to it that it generates an alarm. Till now what we have received is that the 3 legs inside the Ao module see each other and and based on the mismatch the error is flagged.

However, this doesn't lead to anything that we can validate in the loop, be it in terms of current, voltage or resistance.

Has anybody came across such an alarm and have been able to diagnose, would like to share their experience?
Hi all!

I strongly advise you to get a read on thi sthread:
https://control.com/forums/threads/external-mismatch-alarm-in-triconex-ao-card.47374/

Hope this can highlight some points !



James
 
Hi all!

I strongly advise you to get a read on thi sthread:
https://control.com/forums/threads/external-mismatch-alarm-in-triconex-ao-card.47374/

Hope this can highlight some points !



James
Hi James,

I went through the shared thread. We have already exhausted troubleshooting the possible cause mentioned in article and responses in the thread. The AO card that was installed and the new spare that was installed later on doesn't have that issue, (issue means the problem identified in certain batch of AO cards as mentioned in the Triconex technical advisory). This was confirmed by Schneider Electric.

Regards
Gaurav
 
Hi James,

I went through the shared thread. We have already exhausted troubleshooting the possible cause mentioned in article and responses in the thread. The AO card that was installed and the new spare that was installed later on doesn't have that issue, (issue means the problem identified in certain batch of AO cards as mentioned in the Triconex technical advisory). This was confirmed by Schneider Electric.

Regards
Gaurav
Hi Gaurav,

Thanks for your feedback!
Any updates on the evolution on this issue...
I will have a better read on the thread and then will come back for comments..

Regards,
James
 
Here one post describing a case close/similar to yours at site...

https://control.com/forums/threads/triconex-esd-do-output-card.32712/

Have a good read!

Do you have a read on Triconex planing and installation guide...
It can be kind of triac protection or Hart module interface problem...
YOU GOT TO BE SURE THAT the card is healthy...

Also have a read on the Triconex system description manual...it can highlight your mind on what is happening on site...

James
 
Did you perform a good read on "field terminations guide" manual for Triconex ....
As there is most of what you need to kn ow on how AO card 3805H is connected /wired /configured with HART module interface ...

Thanks for sharing if so ...

Can we have a schematic on the Field wiring ..AO card 3805H schematic incuding all the necessary devices ....
We can then have a better overview of WHATS GOING ON in this case...

It may related to external field wiring ...or other external fault ( Hart interface module configuration or other issues...)

James
 
I have a read on the manuals and it looks like you can troubleshoot it easily...

Thank you for posting schematic so we can add some notes/tips/comments

Also do you see "load/fuse indicator " ...is there no light or yellow steady ...

James
 
Here is some notes from OEM manuals:


Understanding External Faults 31
Triconex Enhanced Diagnostic Monitor v1.0 User’s Guide
Understanding External Faults
An external fault is a problem with field inputs, field power supplies, terminations, wiring, or
connected devices. Modules report external faults through these indicators:
• For Tricon, the LOAD/FUSE indicator (if available) on the affected module turns
yellow.
• For Trident, the FIELD POWER indicator on the affected module turns yellow. If the
module has a power fault, the FIELD POWER and SYSTEM ALARM indicators on the
main processors also turn on.
If an external fault occurs, you should read the diagnostic messages in the Module Status dialog
box and examine the field inputs, field power supplies, terminations, wiring, and connected
devices.
A controller is subject to the following types of external faults.
For detailed information about faults and module indicators, see the appropriate Planning and
Installation Guide for your controller.
Fault Type Description
Field Fault on Digital
Output Point
A load or fuse problem related to field terminations on the controller,
field wiring, or field devices.
Field Fault on Input Point A faulty power supply.
Power Fault For Tricon, a power fault refers to one of these conditions:
• The field load (power) for a point is missing.
• A point has a blown fuse.
•One of the power supplies is turned off.
For Trident, a power fault refers to the field power supplies that are connected to a specific module.
• Field Power Supply 1 has a problem.
• Field Power Supply 2 has a problem.
• There is a problem with field inputs, field power supplies,
terminations, wiring, or connected devices.


For more information about faults and module indicators, see the appropriate Planning and
Installation Guide for your controller!

I think that OEM manuals are very useful and well documented!

Please do not hesitate to share your opinion!

James
 
32 Chapter 2 Monitoring Controller Hardware
Triconex Enhanced Diagnostic Monitor v1.0 User’s Guide

Locating and Correcting External Faults

This procedure explains how to locate and correct external faults on a module. Before you begin,
the diagnostic PC must be connected to the network, and the node being monitored must be
open. For instructions, see Opening a Network Node on page 20.
For detailed information about fault conditions, see the appropriate Planning and Installation
Guide for your controller.
Procedure
1 In the System Overview tree, click System Overview to view the chassis or IOP alarm
icons.
2 If an alarm is on (red), open the Module Status window, and then double-click a module
with a yellow indicator.
3 In the Module Status dialog box, click these tabs to locate the fault details:
• For Tricon, click the Field Faults and Power Faults tabs.
 
Clearing Faults on All Modules
This procedure explains how to clear the faults on all modules in a controller. Before clearing
faults, you should identify the causes of the faults and correct them.
You must have read/write access to the controller to clear faults. If you are connected in read-
only mode (see Connecting in Read-Only Mode on page 21), you cannot clear faults.
Note If the Clear Faults on All Modules command is unavailable when connected to a Tricon
node that has a TCM installed, verify in TriStation 1131 that the IP address of the
diagnostic PC has read/write access to the TCM via the TriStation protocol.
If the TCM client access list has been configured so that the IP address of the diagnostic
PC has read-only access to the TCM via the TriStation protocol, you will be unable to
clear all faults. For more information, see the TriStation 1131 Developer’s Guide
 
Creating and Managing Users 11
Triconex Enhanced Diagnostic Monitor v1.0 User’s Guide
Note Even if you are not changing the password, you must enter a password in the
Password and Verify Password fields to confirm the other changes to the user’s
information.
You should enter the user’s existing password in these fields. If you don’t know
the user’s password, you can enter a new password in these fields; just be sure to
tell the user their new password.
5 Click OK to save your changes.
Changing the Security Level for Privileges
This procedure explains how to change the security level required for privileges to Enhanced
Diagnostic Monitor operations. Each operation can be assigned one or more security levels,
from the highest level (01), to the lowest level (10).
Each security level includes a set of privileges for that level, which also includes the privileges
for lower levels. For example, if the operation is set to level 04, users with level 01, 02, and 03
privileges also have access to the operation.
Only users with level 01, 02, or 03 access (and that have also been assigned the Security: Change
level privileges privilege) can change security level privileges.
Enhanced Diagnostic Monitor privileges include the following:
Privilege Description
Default
Security Levels
Module:
Clear faults
Allows the user to clear faults on a module, if they also
have read/write permissions to the module. Applies to
both Tricon and Trident controllers.
Note: Under normal operation, faults are cleared
automatically when the problem causing the fault
is fixed. The Clear Faults command should be used
only in rare circumstances when a fault is not
automatically cleared. As a result, permission to
use this command should be granted only when
needed.
For more information, see Clearing Faults on All Modules
on page 35.
Levels 01—05
Module:
Log system events
Allows the user to collect system events when connected
to a node (controller). Applies to both Tricon and Trident
controllers.
For more information, see Collecting and Viewing Tricon
System Events on page 48 or Collecting Trident System
Events on page 64.
Levels 01—05
 
Tricon Module Status Dialog Box
For each module in a Tricon controller (including the power supplies and Main Processor
modules), the Module Status dialog box displays information about faults.
To open the Module Status dialog box, double-click on any module in the Module Status
window.
Tab s Description
Field Faults Displays load or fuse faults related to field inputs, terminations, wiring, or devices.
(Field faults are not applicable to Main Processors.)
Power Faults Displays faults related to missing field loads (power) or blown fuses; or power
problems which are internal to the controller.
Voter Faults Displays faults in the OVD (Output Voter Diagnostic) circuitry of a digital output
module.

Legend Describes what the colors mean for the slot and LED indicators.


Are you using such tools ??
 
Can the original poster try to respond to the last thread ...
It would be much appreciated ! as we are not here to discuss in the wind !

I mean we make effort to reply so please try to do the same...gentlemen.

Thank you for your attention& comprehension

James
 
Tricon Module Status Dialog Box
For each module in a Tricon controller (including the power supplies and Main Processor
modules), the Module Status dialog box displays information about faults.
To open the Module Status dialog box, double-click on any module in the Module Status
window.
Tab s Description
Field Faults Displays load or fuse faults related to field inputs, terminations, wiring, or devices.
(Field faults are not applicable to Main Processors.)
Power Faults Displays faults related to missing field loads (power) or blown fuses; or power
problems which are internal to the controller.
Voter Faults Displays faults in the OVD (Output Voter Diagnostic) circuitry of a digital output
module.

Legend Describes what the colors mean for the slot and LED indicators.


Are you using such tools ??
Hi James,

We have these applications as these are standard applications supplied with every triconex products.
There also the same error appears "External mismatch error".

We still haven't been able to identify the mechanism through which this alarm is generated in the AO card so the we can target the cause, whether the field or the system side.
 
Hi James,

We have these applications as these are standard applications supplied with every triconex products.
There also the same error appears "External mismatch error".

We still haven't been able to identify the mechanism through which this alarm is generated in the AO card so the we can target the cause, whether the field or the system side.
Hi Gsharma611,

Thank you for your reply!

Well did you have check the Hart module interface ...see if configuration is
correct..

Or any other AO module interface like panel wiring ...as per OEM manual

James

James
 
Hi Gsharma611,

Thank you for your reply!

Well did you have check the Hart module interface ...see if configuration is
correct..

Or any other AO module interface like panel wiring ...as per OEM manual

James

James
Hi James,

The termination boards used with the AO cards are ELCON made boards with HART multiplexers. From termination board there is separate connection for the Asset management system and the 4-20mA loop continues to the AO card through ELCO cables.
Can HART signals affect the 4-20mA signal? (Because card is generating alarm based on this 4-20mA loop)

Regards
 
Hi Gsharma611

Is that HART 2870 INTERFACE MODULE that you are referring too ...

Yes right, I know that there is MUX 2071 HART MODULE integrated with. 98356-10 Panel..you may have to investigate on this path !

It can be the source of issue as you stated , but you still didnot tell me about colors of indicators if it is dispalying "Load /fuse " fault by the mentionned card.

I will have a better study on the devices and field wiring terminations ..

Regards,
James
 
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