INTRODUCTION:

We have Foxboro DCS system (I/A) acting as Foundation Fieldbus host for various FF devices including Yokogawa FF transmitters.

BACKGROUND:

1. DCS I/O card for FF is called FBM228 (Fieldbus module #228) and is assuming LAS (Link Active Schedule) role in the segment.

2. FBM228 is working as redundant pair with fixed device address of 16 (0x10) and 17(0x11).

3. We configure 1 FF device per segment as Link Master device (device address 18 (0x12)) to resume LAS role as long as FBM228 is down for whatever reason.

4. In some segments we have YTA320 and EJA / EJX acting as Link master devices.

5. We are using correct DD files with CFF equipped with Link master capability.

6. We followed Yokogawa device manual give YTA320 transmitter device address 20 (0x14), all parameters (Slot Time, MRD, MID) are the same for

FBM228, YTA320, NI-FBUS card.

ISSUE:

We have continuous error message "Backup LAS deployment: Failed" of Yokogawa devices on DCS system manager.

 

Link Master (backup LAS) functionality in field device is disabled by default. Make sure it is first enabled

In item 3 you say address 18 but in item 6 you say address 20. Is this mismatch the cause?

If you use redundant interface cards you don't need backup LAS in the field device

Cheers,
Jonas